Located at the base of your neck, the thyroid gland is a butterfly-shaped gland that plays a critical role in regulating overall hormonal balance, metabolism, heart rate, body temperature, and overall hormonal balance.

Thyroid removal surgery, or a thyroidectomy, refers to the surgical removal of the thyroid. This safe procedure is often performed to treat various conditions, such as thyroid cancer, large goitres or hypothyroidism that does not respond to other conservative forms of treatment. 

If you ever need to undergo thyroid removal surgery, this article will guide you through everything you need to know and what to expect. Fret not! With proper management and the right follow-up care, it is possible to lead healthy lives post-surgery.

Understanding thyroid disorders

Your thyroid may be small, but it plays an important role in your body. This little gland produces hormones that keep our vital bodily functions running [1], such as your metabolism, energy levels, body temperature, and even your heartbeat. When something’s not quite right with your thyroid gland, it can throw your body out of balance.

In most cases, doctors aim to preserve as much of the thyroid as possible. Sometimes, partial removal is preferred when feasible to reduce the need for lifelong hormone replacement.Here’s a closer look at the thyroid problems that might lead to surgery, what signs to look out for, and when to talk to your doctor.

Common thyroid disorders that may need thyroid removal surgery

• Hyperthyroidism — This condition develops when your thyroid goes into overdrive and pumps out too many hormones. One of the usual causes of this condition is Graves’ disease. While many people can effectively manage it with medication, surgery may be recommended if the condition is severe, keeps coming back, or isn’t responding well to other treatments.
  
• Thyroid nodules — These lumps or bumps that form in the thyroid are usually harmless, but can sometimes become cancerous. If a nodule is large, keeps growing, or looks suspicious on scans or biopsy, your doctor may suggest surgical removal.
  
• Goitre — A goitre is an enlarged thyroid that can develop due to reasons such as iodine deficiency, hormone imbalances, or multiple nodules forming together. If a goitre grows too big, it may press on the windpipe or esophagus, making it difficult to breathe or swallow. That’s when thyroid removal surgery may be recommended.
  
• Thyroid cancer — Thyroid cancer is one of the more treatable cancers if caught early, and the first step is usually removing all or part of the thyroid. In many instances, it’s caught during a routine scan or check-up. If cancer is confirmed, surgery is usually the recommended treatment, followed by others if needed.

Symptoms of thyroid conditions to look out for

As the thyroid is heavily involved in homeostasis of the body, dysfunction can lead to symptoms affecting various systems — from our energy levels, menstrual cycles, and even temperature regulation. Keep an eye out for symptoms such as:

• A visible or growing lump in your neck
  
• Difficulty swallowing or breathing
  
• Unexplained weight changes
  
• Feeling tired, anxious, or shaky
  
• Irregular or heavy periods
  
• Changes in your voice, such as hoarseness
  

Risk Factors 

You’re more likely to develop thyroid issues if:

• Someone in your family has had thyroid problems
  
• You’ve had radiation exposure [2], especially to your neck or head area
  
• Your iodine intake is too low or too high
  
• You are female, as women are more prone to thyroid disorders, especially during pregnancy or menopause
  

Types of Thyroid Removal Surgery

If your doctor has recommended thyroid surgery, the type of surgery you’ll need depends on your specific condition. Thyroid removal surgery is done under general anaesthesia, putting you to sleep throughout the entire procedure. 

A conventional surgery involves an incision at the lower front of your neck, while modern options like endoscopic or robotic-assisted surgery utilise smaller incisions, reducing scarring significantly. A transoral approach (through the mouth) leaves no visible external scar at all. 

Here’s a look at different types of thyroid surgeries:

Total Thyroidectomy

This involves removing the entire thyroid gland, and is often recommended for thyroid cancer, or in cases where both lobes of the thyroid are affected, like in Graves’ disease. After a total thyroidectomy, you’ll be required to take thyroid hormone replacement for life to maintain normal bodily functions.

Partial Thyroidectomy

A partial thyroidectomy (also called a thyroid lobectomy or hemithyroidectomy) involves removing just one lobe of the thyroid gland. It’s usually done when there is a nodule or tumour on one side of the thyroid.

The type of surgery that you undergo will depend on your consulting surgeon. At NC Tan Surgery in Singapore, we take the time to understand your condition thoroughly, whether it's a thyroid nodule, goitre, or abnormal hormone levels. With personalised assessments and diagnostics, along with a patient-first approach, we’ll help you make the right decision for your health. Book a consultation today and find out if surgery is the right step for you.

When is thyroid removal surgery recommended?

Thyroid surgery is generally considered one of the last treatment options recommended — when less invasive methods aren’t effective or appropriate. 

Your doctor might recommend surgery due to the following reasons:

• Medications aren’t working or causing unwanted side effects
• Risk of or confirmed diagnosis of thyroid cancer
• A goitre or nodule pressing on your windpipe or esophagus
• Condition and symptoms keeps returning or worsening despite treatment

Before anything is decided, you will undergo a thorough assessment. This includes blood tests, ultrasound scans, and sometimes, a biopsy. These tests help your specialist decide whether surgery is truly needed and what type would be best for you.

How to prepare for thyroid removal surgery

Once surgery is confirmed, preparation is key. Your surgeon will walk you through the steps required. Generally, before any procedure is undertaken, the following diagnostic tests are conducted:

• Blood tests — To check thyroid function and calcium levels
  
• An ECG or imaging scans — Especially if there are other health concerns
  
• Medication review — You may need to pause or adjust some prescriptions temporarily

How much does thyroid removal surgery cost in Singapore?

You will also need to prepare financially for thyroid removal surgery. In Singapore, thyroid surgery itself can cost anywhere from SGD 8,000 to 15,000. Most procedures are MediSave-claimable, and insurance often covers a significant portion. It’s always worth checking your coverage ahead of time to stay well-informed of costs and payments. 

The thyroid removal surgery process: what to expect

Knowing what to expect for thyroid removal surgery can help ease anxieties and prepare for recovery afterwards. The surgery is done under general anaesthesia, and most procedures take about 1.5 to 3 hours. You may need to stay in the hospital for a night or two, depending on the type of surgery and to make sure you are healing well.

After the procedure, you might feel a bit sore in the neck area and have a drain placed temporarily to manage fluid. Some people notice a hoarse voice, but this usually improves over time. You should be back on your feet within a few days and can return to your usual activities, such as work, in one to two weeks. A full recovery usually takes approximately three weeks. 

As with any surgery, there are some risks. These include temporary or long-term voice changes, low calcium levels if parathyroid glands are affected, and infection or bleeding. Your surgeon should discuss these with you based on your risk profile.

Life after thyroid removal

If your entire thyroid is removed, you will need to take daily thyroid hormone replacement tablets. This keeps your body functioning normally. Your doctor may recommend taking calcium and vitamin D supplements, staying well-hydrated, and avoiding high-iodine foods unless advised otherwise. 

Regular follow-up appointments will also be scheduled, along with blood tests to monitor your hormone levels and adjust medication as needed. If cancer was involved, your follow-up plan may also include imaging or further treatment.

Summary

Thyroid issues can feel overwhelming, and symptoms can impact your quality of life. However, with the right care and early intervention, such as thyroid removal surgery, most people go on to live full and healthy lives. 

If you’re experiencing symptoms or facing a diagnosis, understand that there are options and treatments available to you. We suggest you speak with a specialist, ask questions, and explore your options, as early treatment can make all the difference. Schedule a consultation for a detailed diagnosis and personalised treatment plan.

Frequently Asked Questions

Will I need medication for life after thyroid surgery?
Yes, if your entire thyroid is removed. However, if part of it remains, you may not need lifelong medication, but will need to monitor your hormone levels through regular blood tests.

Is thyroid removal surgery painful?
You will be under anaesthesia during the surgery, so you will not feel any pain during the procedure. Afterwards, some people experience mild discomfort, which can be managed with painkillers.

Will I have a scar after thyroid removal surgery?
Yes, but it usually fades over time. Minimally invasive techniques can help reduce visible scarring.

References

1. InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-. In brief: How does the thyroid gland work? [Updated 2024 May 28]. Retrieved from: https://www.ncbi.nlm.nih.gov/books/NBK279388/

2. Iglesias, M. L., Schmidt, A., Ghuzlan, A. A., Lacroix, L., Vathaire, F., Chevillard, S., & Schlumberger, M. (2017). Radiation exposure and thyroid cancer: a review. Archives of endocrinology and metabolism, 61(2), 180–187. Retrieved from: https://doi.org/10.1590/2359-3997000000257

Have you ever wondered how our body keeps our calcium levels in check? It’s all thanks to our parathyroid glands — four small glands tucked behind our thyroid. They play a huge role in bone health, nerve function, and even how our muscles work.

Although parathyroid gland disorders are often subtle, abnormal calcium levels, muscle weakness or brittle bones may be indicative of the condition, and worth consulting your doctor. In this article, we’ll walk you through the two main types of parathyroid gland disorders, when to visit a doctor, and what to expect. 

Understanding the parathyroid glands

The parathyroid glands are 4 small glands located at the back of the thyroid gland, the butterfly shaped gland in our throat. The main function of these glands are to produce and secrete parathyroid hormone (PTH), the hormone responsible for the regulation of calcium levels in our blood.

When calcium levels in our body become too low, the PTH, along with vitamin D, induce absorption and reabsorption of calcium from the digestive system and the kidneys. In the bone, PTH stimulates osteoclasts to break down bones and release the calcium from the bones into the blood. 

As the levels of calcium in the blood increase, both calcium and vitamin D induce a negative feedback loop to the parathyroid hormones to stop producing PTH, preventing a further increase in blood calcium levels. 

The main function of the parathyroid glands is to regulate or maintain the homeostasis of calcium levels in our blood. Hence, disorders of the parathyroid hormone will often present as problems caused by an imbalance of serum calcium. Often, this leads to issues in the kidneys, bones, and other conditions.

Parathyroid disorders: what they are and how they’re caused

Hyperparathyroidism

Hyperparathyroidism is characterised by overactive parathyroid glands, which result in too much PTH being released. This can lead to dangerously high levels of calcium in the blood. Hyperparathyroidism is mainly categorised as primary and secondary hyperparathyroidism, while tertiary hyperparathyroidism is often considered as a complication of unmanaged hyperparathyroidism.

• Primary hyperparathyroidism – Primary hyperparathyroidism is caused by an overproduction of PTH by the parathyroid glands. This can be attributed to parathyroid hyperplasia (overgrowth or enlargement of the parathyroid glands), adenoma (benign parathyroid tumour), or carcinoma (parathyroid cancer).
  
• Secondary hyperparathyroidism – Secondary hyperparathyroidism can be caused by other conditions that lead to a chronic hypocalcaemic state, a condition where your blood calcium levels are abnormally low. This leads to the parathyroid glands making PTH as a response to the low calcium levels. Secondary hyperparathyroidism can be caused by chronic kidney diseases (CKD), calcium deficiency, or vitamin deficiency.
  
• Tertiary hyperparathyroidism – Tertiary hyperparathyroidism is a complication of chronic, untreated hyperparathyroidism. Typically, this is seen in end-stage kidney diseases. The chronically low calcium levels lead to the overgrowth or hyperplasia of the parathyroid gland tissues.

Hypoparathyroidism 

On the other hand, hypoparathyroidism is characterised by low productivity of the parathyroid glands. Impaired function of the parathyroid glands can lead to low levels of calcium, high levels of phosphate, and neuromuscular irritability. This condition is uncommon, and can be caused by:

• Injuries to the parathyroid hormone, usually during head and neck surgery
• Genetic conditions, such as DiGeorge syndrome
• Autoimmune diseases
• Use of medication, such as immune checkpoint inhibitors
• Malnutrition, such as magnesium deficiency
• Radiation injury to the parathyroid glands
• Other illnesses, such as granulomatous disease

Signs and Symptoms to look out for 

Abnormal calcium levels in the body can lead to various signs and symptoms. Common symptoms of parathyroid disorders can include:

	Hyperparathyroidism	Hypoparathyroidism
Cardiovascular symptoms	ArrhythmiaBradycardiaHypertensionHeart palpitation	ArrhythmiaDyspnea or difficulty breathingHypotensionHeart palpitationsFainting
Gastrointestinal symptoms	Abdominal painAnorexiaConstipation Dyspepsia or indigestionNausea and vomitingPancreatitis	Abdominal pain
Musculoskeletal symptoms	Joint painBone painMuscle achesIncreased risk of fractures	Muscle spasmsMuscle cramps
Neurologic symptoms	ConfusionDeliriumDifficulty concentratingImpaired visionLethargyMemory lossSleep disturbances	Tingling sensation or numbness in the hands and feetHeadacheImpaired visionSeizures Involuntary muscle spasms or contractionsDementiaParkinsonism
Psychiatric symptoms	DepressionAnxietyEmotional instability	DepressionAnxiety
Pulmonary symptoms		BronchospasmLaryngospasmWheezing
Renal symptoms	Polydipsia or increased thirstIncreased urinationRenal colic, characterised by severe sudden pain in the kidneysRenal failure
Ophthalmic symptoms		Cataracts

When our calcium levels are out of balance, our whole body can experience its effects. However, this also makes parathyroid gland disorders hard to identify, and symptoms are often mistaken for other issues. 

In most cases, parathyroid disorders are diagnosed incidentally during testing for serum calcium levels when performing tests for renal or bone disorders.

How are parathyroid disorders diagnosed?

Diagnosis of parathyroid disorders typically involve blood tests to measure calcium and PTH levels. Your doctor may perform other tests depending on the symptoms you have at the time of examination. Generally, parathyroid disorders are evaluated based on the following:

• Blood tests – Blood tests are important to evaluate the following:
  
  • Serum calcium levels – Tests involving calcium levels in the blood can be measured as total serum calcium, or ionised serum calcium. Calcium levels in the blood can indicate whether your symptoms are caused by hypercalcaemia or hypocalcaemia.
    
  • PTH levels – PTH levels are also important to differentiate between hyperparathyroidism and hypoparathyroidism. In normal conditions, PTH levels are between 10 – 65 pg/mL.
    
  • Parathyroid-related peptide (PTHrP) – PTHrP is a protein produced in the body in very low amounts. Higher levels of PTHrP typically indicate cancers such as squamous cell lung cancer, squamous cell head and neck cancers, and breast cancers. This test is typically done to rule out malignancies.
    
  • Vitamin D – Vitamin D tests are done to diagnose vitamin D deficiency.
    
• Imaging scan – Sestamibi parathyroid scintigraphy is a parathyroid scan performed to evaluate the size of the parathyroid glands. This test can be used to look for signs of parathyroid adenoma or hyperplasia.
  
• Neurological exams – Hypoparathyroidism can cause muscle twitches or spasms when the nerves are stimulated. Specific tests used to look for signs of hypoparathyroidism are called the Chvostek sign and the Trousseau sign.
  
• Other tests – Other tests are typically performed to assess bodily functions that may be affected by hypercalcaemia or hypocalcaemia. These can include electrocardiogram to assess cardiac activity, urine tests to look for calciuria, and renal ultrasounds to look for the presence of kidney stones.

How are parathyroid disorders treated?

Parathyroid disorders are treated according to the type of disorder and the possible underlying cause.

Hyperparathyroidism

• Primary hyperparathyroidism – Hyperparathyroidism caused by overactive parathyroid glands can be treated with:
  
  • Surgery – Surgical therapy is often done via parathyroidectomy, a procedure involving the removal of one or more parathyroid glands. In most patients, parathyroidectomy can effectively bring calcium levels to a normal range and improve bone mineral density.
    
  • Medications – When surgical treatment is not ideal, such as in elderly patients, or patients with comorbidities, medical treatment is a suitable alternative. Medications are typically given to treat complications of hyperparathyroidism, such as hypercalcaemia or osteoporosis. Common medications used include bisphosphonates for osteoporosis, and calcimimetics, such as cinacalcet, or phosphates to regulate calcium levels.
    
  • Supplements – Vitamin D supplements are also recommended for patients with vitamin D deficiency.
    
• Secondary hyperparathyroidism – Treatment of secondary hyperparathyroidism should involve treatment of the underlying condition or cause of hyperparathyroidism, such as CKD. In addition to that, management of abnormal serum calcium levels are also similar to that of primary hyperparathyroidism.
  
  • Medical therapy – Medical treatment of secondary hyperparathyroidism in CKD patients is typically done by managing serum calcium, phosphate, and vitamin D levels. Common medications used include cinacalcet, phosphate binders (aluminium hydroxide, sevelamer hydrochloride, and sevelamer carbonate), as well as vitamin D metabolites (cholecalciferol and ergocalciferol).
    
  • Surgery – Parathyroidectomy is often indicated if medical treatment was unsuccessful or if symptoms are refractory to the treatment given. Other indications of surgery for secondary hyperparathyroidism include calciphylaxis, refractory itching, severe hypercalcaemia, high phosphate levels, anaemia, chronically high PTH levels, and extraskeletal calcification.

• Tertiary hyperparathyroidism – Treatment for tertiary parathyroidism generally involves addressing the overproduction of parathyroid hormone (PTH) that persists despite correction of the initial cause (usually long-standing secondary hyperparathyroidism in chronic kidney disease patients after renal transplantation). The main focus of treatment is to manage hypercalcaemia and reduce excessive PTH secretion.

• Surgery – Surgery is the definitive treatment for tertiary hyperparathyroidism, especially in patients with persistent hypercalcaemia or high PTH calcifications. It is also recommended in patients who experience symptoms like bone pain, pruritus, and soft tissue or vascular calcifications. 

• Medications – Medications, such as Cinaclet, a calcimimetic agent, can be used to lower serum calcium levels and PTH. Vitamin D analogues and phosphate binders can also be prescribed to stabilise calcium-phosphate metabolism.

Hypoparathyroidism

Treatment of hypoparathyroidism includes: 

• Supplements – Supplements are useful in patients with hypoparathyroidism. Supplements of calcium and calcitriol, a vitamin D metabolite, are typically recommended to maintain serum calcium levels. Patients with parathyroid gland injuries, such as from head and neck surgical procedures, typically get better within a month following oral calcium and calcitriol treatments.
  
• Hormone replacement therapy – Hormone replacement with PTH can also be indicated for patients with hypoparathyroidism who struggle with standard therapy using calcium and calcitriol supplements. Palopegteriparatide is a PTH analogue used for this purpose.

When to visit your doctor 

You should visit a doctor if you experience signs of parathyroid disorders. The symptoms of parathyroid disorders can also resemble other conditions or disorders which may be more serious, hence it is always recommended to visit a doctor for a proper and comprehensive diagnosis.

Summary

Fatigue, bone aches and mood changes could mean more than just everyday stress. Parathyroid disorders can often fly under the radar, but they can greatly impact your overall health. Thankfully, parathyroid disorders are treatable, and often curable, with the right medical care.

Here at NC Tan Surgery, we believe in delivering precise, patient-focused care. Schedule a consultation with us for a detailed diagnosis and personalised treatment plan.

Frequently Asked Questions

How can I prevent parathyroid gland disorders?

Preventing parathyroid gland disorders can involve:

• Taking in enough vitamin D and calcium – Deficiencies of vitamin D and calcium can lead to secondary hyperparathyroidism. Additionally, taking enough vitamin D and calcium also keeps your bones healthy and prevents the risk of osteoporosis.
  
• Managing conditions such as chronic kidney diseases – Managing CKD can reduce the risk of secondary hyperparathyroidism.

Are parathyroid disorders dangerous?

In most cases, the condition is mild to moderate. However, chronic parathyroid disorders can lead to complications that may affect quality of life and increase the risk of mortality and morbidity, such as increased risk of fractures due to osteoporosis.

What happens if parathyroid disorders are left untreated?

Common complications of parathyroid disorders include:

• Osteoporosis – Loss of bone mineral density due to high levels of PTH can lead to osteoporosis, this increases the risk of bone fractures from low-impact trauma, such as falling.
  
• Kidney stones – High levels of calcium in the blood can lead to kidney stone formation.
  
• Cardiovascular diseases – Similarly, high levels of calcium in the blood is linked to an increased risk of heart diseases and high blood pressure.

Thyroid nodules are a common clinical finding, affecting a significant portion of the population worldwide, and Singapore is no exception. With increased health screening, and widespread use of imaging technologies such as ultrasound, and CT scans, more people are being diagnosed with thyroid nodules, often incidentally.

What does it mean if your doctor detects a thyroid nodule — and does it immediately entail surgery? Contrary to common belief, not all nodules require immediate treatment, and determining when surgery is necessary can be complex, and deeply personal.

That being said, it is important to note that some thyroid nodules can grow large enough to cause physical discomfort, affect hormone levels, or more seriously, pose a risk of thyroid cancer. 

What are Thyroid Nodules?

The thyroid is a butterfly-shaped gland located at the front of your neck. It plays a vital role in regulating your body’s metabolism through the production of thyroid hormones. Sometimes, lumps or abnormal growths develop within the thyroid tissue. These are known as thyroid nodules.

Thyroid nodules are relatively common, especially in adults over the age of 40, and in women. Most are discovered during routine physical examinations or imaging tests performed for unrelated conditions. While the majority of nodules are harmless, some may require further investigation or treatment depending on their characteristics.

Meanwhile, a thyroid nodule is a growth or lump that forms within the thyroid gland. It can be:

• A single lump (solitary nodule).
• One of many within an enlarged gland (multinodular goitre).
• Detected during a self-examination, clinical exam or imaging test.

These nodules can vary significantly in size, number, and content. While many remain stable over time, others may grow or change, prompting further evaluation.

Benign vs Malignant Thyroid Nodules

Most thyroid nodules are benign, and many do not require any intervention beyond regular monitoring. However, a small percentage may turn out to be malignant, making early detection, and evaluation essential for timely treatment.

Below is a comparison to help you understand the key differences between benign, and malignant thyroid nodules:

FEATURE	BENIGN NODULE	MALIGNANT NODULE
Nature	Non-cancerous	Cancerous, such as:Anaplastic.Follicular.Medullary.Papillary.
Prevalence	Over 85% of thyroid nodules are benign.	Less than 10% of nodules turn out to be malignant.
Growth Rate	Usually slow or stable.	May grow rapidly or show irregular features.
Symptoms	Often asymptomatic, but may cause pressure if large.	May cause hoarseness, difficulty swallowing or neck pain.
Appearance on Ultrasound	Smooth borders, cystic or spongiform, no calcifications.	Irregular margins, microcalcifications, increased blood flow.
Biopsy Findings	Benign cells, low risk of cancer.	Suspicious or confirmed cancer cells.
Treatment Approach	Monitoring or minor procedures.	Surgery is usually recommended.

What do Thyroid Nodules look like?

Thyroid nodules can be classified based on their physical structure, such as:

TYPE OF NODULE	DESCRIPTION	CLINICAL SIGNIFICANCE
Solid Nodule	Entirely composed of thyroid tissue or abnormal cells.	May require biopsy if suspicious features are present.
Cystic Nodule	Fluid-filled, often benign.	Usually monitored unless large or symptomatic.
Mixed (Complex) Nodule	Contains both solid, and fluid components.	May need further investigation depending on ultrasound findings.

How do Thyroid Nodules develop?

The formation of a thyroid nodule is often the result of complex interactions between genetic, environmental, and hormonal factors. While many nodules remain harmless, identifying their root causes can help patients, and doctors make informed decisions about monitoring or treatment.

These potential causes include:

• Iodine Deficiency – iodine is a key mineral required by the thyroid gland to produce hormones. In areas with low iodine intake, such as parts of Southeast Asia before widespread salt iodisation, the thyroid may overwork to maintain adequate hormone levels. This overstimulation can lead to thyroid cell proliferation, resulting in glandular enlargement, and the eventual formation of nodules. 

• Thyroiditis – chronic inflammation of the thyroid, particularly in Hashimoto’s thyroiditis, is another common trigger. In autoimmune thyroiditis, the body’s immune system mistakenly attacks the thyroid gland, causing damage over time. As the thyroid tries to repair itself, areas of abnormal cell regeneration may develop, forming scar tissue or nodules. These nodules are usually benign but can coexist with thyroid dysfunction, such as hypothyroidism.

• Genetic Predisposition – a family history of thyroid disease, especially thyroid nodules, goitres or thyroid cancer, increases the risk of developing nodules. Certain genetic mutations are associated with abnormal growth patterns within the gland, which may predispose individuals to both benign and malignant nodules. In some cases, inherited syndromes such as multiple endocrine neoplasia (MEN) can also lead to the development of thyroid cancers, particularly medullary thyroid carcinoma.

• Environmental and Lifestyle Factors – exposure to radiation, especially during childhood, is a well-documented risk factor for thyroid nodule development, and thyroid cancer. This includes radiation therapy for other conditions or environmental exposure from nuclear fallout. Additionally, lifestyle factors such as smoking and, stress, though less direct, may contribute to thyroid dysfunction, and inflammation, indirectly leading to nodule formation over time.

Symptoms of Thyroid Nodules

Most of the time, thyroid nodules do not cause noticeable symptoms. However, some individuals may experience:

• A sensation of tightness in the throat.
• A visible lump or swelling in the neck.
• Difficulty swallowing or breathing.
• Hoarseness or voice changes.
• Persistent coughing that is not related to a cold.

How Thyroid Nodules affect your health and daily life

In the early stages, thyroid nodules are often asymptomatic, which means many people do not even realise they have one. While the absence of early symptoms may seem reassuring, it can also lead to delayed diagnosis, particularly when nodules begin to grow or affect thyroid function gradually over time.

As thyroid nodules enlarge or become hormonally active, they may start to cause noticeable physical, functional, and emotional impacts. These effects can disrupt everyday life and may indicate the need for medical intervention.

Here is how thyroid nodules can affect your health, and daily routine:

FACTOR	HOW IT IMPACTS HEALTH AND DAILY ROUTINE
Physical Discomfort and Cosmetic Concerns	A growing thyroid nodule can cause a visible lump in the neck, which may lead to discomfort, self-consciousness or concern about appearance, especially when the nodule is large or situated prominently.
Pressure Symptoms	Enlarging nodules may compress nearby structures in the neck, leading to: Difficulty swallowing due to oesophageal compression.Hoarseness or voice changes from pressure on the recurrent laryngeal nerve.Tightness or fullness in the neck.Persistent coughing or shortness of breath and, in rare cases, due to tracheal compression. These symptoms can interfere with eating, speaking, or breathing comfortably, thus significantly impacting daily activities.
Anxiety About Malignancy	Even if a nodule is likely benign, the uncertainty surrounding its nature can cause significant emotional distress. Patients often experience anxiety about the potential for cancer, especially when biopsies return inconclusive results. This psychological burden may persist until a clear diagnosis is made.
Hormonal Imbalances	Some thyroid nodules may be hot or hyperfunctioning, meaning they produce excess thyroid hormones. This can result in hyperthyroidism, which causes: Anxiety or irritability.Heat intolerance.Palpitations.Tremors.Weight loss. In contrast, hypothyroid nodules, often due to Hashimoto’s thyroiditis, may lead to fatigue, weight gain, cold intolerance, and dry skin. These hormonal fluctuations affect not only physical health but also emotional wellbeing, energy levels, and concentration, further interfering with quality of life.

When is surgical treatment necessary?

While many thyroid nodules do not require surgery, there are certain situations where surgical removal becomes the safest and most effective treatment. The decision to operate depends on factors such as nodule size, function, cancer risk, symptoms, and patient preference.

Below is a summary of common indications for thyroid surgery:

INDICATION	CHARACTERISTICS
Confirmed or suspected thyroid cancer	Nodules with malignant features or positive biopsy require removal for cure.
Large nodules causing compressive symptoms	Nodules that press on the trachea or oesophagus, causing difficulty swallowing or breathing.
Hyperfunctioning nodules	Nodules producing excess hormones unresponsive to medication or radioiodine.
Indeterminate biopsy results	Nodules with inconclusive cytology may be removed to rule out malignancy.
Cosmetic concerns or patient preference	Surgery may be considered for visible, unsightly lumps even if benign.
Multinodular goitre with symptoms	Multiple enlarging nodules affecting function or appearance.

Risks of delaying surgery

For some individuals, delaying surgery for thyroid nodules can lead to complications that may affect both health, and outcomes. These include:

• Increased surgical complexity, as larger nodules may involve surrounding structures or cause scarring.
• Nodule enlargement, leading to worsening pressure on the airway or oesophagus.
• Progression to thyroid cancer, particularly in nodules with suspicious features.
• Voice changes or swallowing difficulties, as nerves or muscles become compressed.
• Worsening hyperthyroidism, increasing the risk of heart rhythm disturbances or osteoporosis.

What are the surgical options for Thyroid Nodules?

Once a thyroid nodule has been carefully assessed, through physical examination, ultrasound imaging, blood tests, and often a fine needle aspiration biopsy (FNAB), our doctor may recommend surgery if there is a significant risk of cancer, troublesome symptoms or other clinical concerns.

Before selecting the appropriate surgical approach, several key factors are considered, including:

• The patient’s age, overall health, and preference.
• The size, location, and number of nodules.
• Whether the nodule is benign or malignant.
• Whether the nodule is causing hormonal imbalance or compressive symptoms.
• Whether there is disease in one or both lobes of the thyroid.

Lobectomy (Hemithyroidectomy)

A lobectomy involves the removal of one lobe of the thyroid gland. The remaining lobe is usually left intact, allowing some natural hormone production to continue.

Which type of nodule is it suitable for?

• Solitary benign nodules confined to one lobe.
• Small, low-risk papillary or follicular thyroid cancers.
• Indeterminate nodules where only part of the thyroid is affected.

Total Thyroidectomy

A total thyroidectomy involves the removal of the entire thyroid gland. This option is more definitive and often used in higher-risk cases.

Which type of nodule is it suitable for?

• Confirmed thyroid cancer, especially if bilateral or aggressive.
• Large goitres or multinodular goitres.
• Recurrent or multifocal nodules.
• Patients requiring radioactive iodine therapy post-surgery.

Minimally Invasive Thyroid Surgery

This approach uses smaller incisions. and specialised instruments to reduce surgical trauma. and promote faster healing.

Which type of nodule is it suitable for?

• Benign nodules in patients seeking less visible scarring.
• Small, well-localised nodules.
• Select low-risk cancers.

Endoscopic or Robotic-Assisted Thyroid Surgery

These minimally invasive techniques use an endoscope or robotic system to assist in thyroid removal through incisions that are hidden, such as under the arm and chest.

Which type of nodule is it suitable for?

• Cosmetic concerns, such as patients who prefer no visible neck scar.
• Small, benign nodules or select early-stage cancers.
• Patients meeting strict eligibility criteria.

Risks and benefits of thyroid surgery

Thyroid surgery is generally safe, and effective, especially when performed by experienced surgeons. It provides relief for patients with troublesome thyroid nodules, cancer concerns or hormonal imbalance. However, like all surgical procedures, it carries certain risks.

Risks of Thyroid Surgery

RISK	OUTCOME
Voice changes or hoarseness	The recurrent laryngeal nerve, which controls vocal cord movement, lies near the thyroid. If irritated or injured during surgery, it may cause temporary or, rarely, permanent voice changes.
Hypocalcaemia	If the nearby parathyroid glands are affected during surgery, patients may develop low calcium levels, leading to numbness or muscle cramps. This is usually temporary, and manageable.
Bleeding or haematoma	A rare but serious complication where bleeding occurs post-surgery, potentially compressing the airway, and requiring urgent treatment.
Infection	Though uncommon, any surgical site can become infected. It is typically mild, and treated with antibiotics.
Need for lifelong medication	Patients undergoing total thyroidectomy will need daily thyroid hormone replacement for life, which requires regular monitoring, and dose adjustments.

Benefits of Thyroid Surgery

BENEFIT	OUTCOME
Definitive diagnosis and treatment	For indeterminate or suspicious nodules, surgery provides a clear diagnosis, and removes the problematic tissue.
Relief from physical symptoms	Surgery alleviates discomfort caused by large nodules, including difficulty swallowing, breathing issues, and pressure sensations.
Elimination of cancer	In cases of thyroid cancer, surgical removal of the thyroid can be curative, especially when detected early.
Improved cosmetic appearance	Surgery can address visible neck lumps, which may be a source of self-consciousness or distress.
Peace of mind	Knowing that the suspicious or symptomatic nodule has been removed provides emotional relief, and reduces anxiety about future risks.

Summary

Thyroid nodules are common, and often harmless, but they deserve careful attention, especially when they grow, cause symptoms or raise concerns about cancer. Many people live with thyroid nodules without even knowing, until symptoms such as a neck lump, swallowing difficulty or voice changes prompt further investigation.

Whether it is a small benign nodule or a suspicious lesion, treatment can be personalised to your needs, and health goals. Thyroid surgery is not always necessary, but when it is, it can provide clarity, relief, and peace of mind. Schedule a consultation with us today, for a detailed diagnosis and personalised treatment plan.

Frequently Asked Questions

Can thyroid nodules go away on their own?
Some benign thyroid nodules, especially simple cystic nodules, may shrink or even disappear over time without treatment. However, most remain stable or grow slowly. It is essential to attend regular check-ups to monitor for any changes in size, function or appearance.

How fast do thyroid nodules grow?
The growth rate can vary widely. Slow, gradual growth is more typical of benign nodules, while rapid enlargement may raise suspicion for malignancy or bleeding within the nodule. Any noticeable increase in size should be evaluated promptly by a specialist.

Do all thyroid nodules require surgery?
No. Surgery is only necessary in selected cases, typically when nodules are:

• Functionally overactive, in other words, producing excess hormones.
• Indeterminate on biopsy.
• Large, and causing symptoms.
• Suspicious or confirmed to be cancerous.

Is surgery the only treatment for thyroid nodules?
Not always. Depending on the nodule’s nature, and behaviour, alternative options include:

• Ethanol ablation – a minimally invasive option for certain fluid-filled (cystic) nodules.
• Radioactive iodine therapy – effective for treating hyperfunctioning nodules.
• Observation – especially for small, benign or asymptomatic nodules.

What is recovery like after thyroid surgery?
Most patients recover quickly. You may stay in hospital for 1 night, with full recovery within 1 to 2 weeks. Apart from that, you will also be asked to adhere the following post-care tips:

• Follow-up consultations to adjust medication and assess healing.
• Monitoring of thyroid hormone and calcium levels.
• Voice rest if vocal strain occurs.
• Wound care to ensure proper healing.

Is a thyroid nodule always a sign of cancer?
No. In fact, over 85% of thyroid nodules are benign. While any new lump should be assessed, a thorough evaluation, including ultrasound, and biopsy, can determine the risk. Many benign nodules never require treatment. 

Can I live a normal life after thyroid surgery?
Yes. Most people resume normal daily activities after surgery. If the entire thyroid is removed, you will need lifelong thyroid hormone tablets, but with proper monitoring, these allow you to lead a completely normal life. Furthermore, regular follow-up ensures long-term health, and hormonal balance. 

Does having a thyroid nodule affect pregnancy or fertility?
Not necessarily. However, thyroid function plays a role in fertility, and pregnancy health. If you are planning to conceive or are already pregnant, it is important to monitor thyroid hormone levels and ensure nodules are not causing dysfunction. 

Head and neck cancer encompass a wide variety of malignancies, including the mouth, throat, larynx, sinuses and salivary glands. Although lumps and swelling are some of the most common early warning signs, they don’t always equate to cancer. 

With that said, there are other symptoms that may signal head and neck cancer, making it crucial to pay attention to our body. Read on to find out more!

What is Head and Neck Cancer?

Head and neck cancer encompasses a group of cancers that originate in the mouth, throat, sinuses, and salivary glands. These areas are lined with mucosal surfaces, where abnormal cell growth can occur, leading to cancer. The types of head and neck cancer include:

Types of Head and Neck Cancer

Head and neck cancer are categorised based on its point origin. This includes:

• Oral Cancer – oral cancer is a type of cancer that often starts as persistent sores or lumps that do not heal. It develops in the areas of the mouth, such as lips, gums, tongue, inner lining of the cheeks and lips, roof, and floor of the mouth, and areas near the wisdom teeth.

• Salivary Gland Cancer – salivary gland cancer is a cancer affecting the salivary glands, which are responsible for producing saliva. This type often presents as swelling or a lump near the jaw or under the tongue, sometimes accompanied by pain or dry mouth.

• Nasal Cavity and Paranasal Sinus Cancer – this type of cancer forms in the nasal cavity, which is the hollow space inside the nose. It can also develop in the paranasal sinuses, which are the air-filled spaces around the nasal cavity.

• Nasopharyngeal Cancer – nasopharyngeal cancer originates in the nasopharynx, which is the upper part of the throat located behind the nose.

• Oropharyngeal Cancer – oropharyngeal cancer arises in the oropharynx, which is the middle part of the throat that includes the tonsils, and the base of the tongue.

• Hypopharyngeal Cancer – hypopharyngeal cancer develops in the hypopharynx, which is the lower part of the throat that surrounds the larynx.

• Laryngeal Cancer – laryngeal cancer affects the larynx or voice box, which houses the vocal cords.

How to tell cancerous and benign lumps apart

Lumps associated with head and neck cancers differ from benign lumps like cysts in several notable ways:

Feature	Head and Neck Cancer	Benign Lumps (Cysts and Nodules)
Duration	Stays the same or keeps growing, doesn’t shrink.	May shrink, grow, or disappear over time.
Texture & firmness	Hard, firm, doesn’t move when touched.	Soft or rubbery, can often be moved under the skin.
Pain	Usually painless at first, but may hurt as it grows in size.	Can be tender or painful, especially if red and inflamed.
Growth rate	Slow and steady growth	May change in size, but often temporary
Other symptoms	Voice hoarseness, swallowing problems, ear pain or unexplained weight loss	Generally no serious symptoms unless infection occurs.
Location & risks	More common in the throat, mouth, jaw or neck.	Can appear anywhere

Other common symptoms of head and neck cancer

• Facial swelling and changes – tumours can cause asymmetry in the jaw, neck or face, leading to visible deformities.

• Lumps in the neck – these lumps may feel firm, painless or fixed. However, it is often an indicator of lymph node involvement.

• Mouth lumps or ulcers – this refers to persistent sores or lumps in the mouth or tongue that do not heal.

• Salivary gland tumours – this refers to swelling the parotid, submandibular or sublingual glands, accompanied by pain or dry mouth.

• Swelling in the throat – this may cause difficulty swallowing or breathing.

When to see a doctor

It’s always best to be on the safe side when it comes to your health. Seek medical attention if you experience persistent or concerning symptoms because early detection can make all the difference. Similarly, it is essential to pay particular attention to multiple symptoms occurring simultaneously, such as lumps, unexplained bleeding or chronic pain. 

Common risk factors for head and neck cancers 

In Singapore, head and neck is fairly common, with more than 800 new cases [1] are diagnosed annually. The most prevalent type is nasopharyngeal carcinoma (NPC), which is often referred to as nose cancer. In fact, it is one of the top 10 most common types of cancer in Singapore.

With such prevalence, understanding individual risk factors is one of the proactive measures that an individual can take to safeguard their health. This includes:

• Alcohol consumption – heavy, and prolonged alcohol [2] intake is closely associated with cancers of the mouth, throat and voice box. In fact, the risk is even higher for individuals who both smoke, and drink.

• Tobacco use – the use of cigarettes, cigars, chewing tobacco or other tobacco products significant increases [3] the risk of head and neck cancers. As a matter of fact, it remains the leading preventable cause of these cancers.

• Genetic factors – a family history [4] of head and neck cancer or related conditions can predispose individuals to a higher risk, emphasising the importance of regular screenings.

• HPV infection – the human papillomavirus (HPV) infection, particularly the HPV-16 [5], is strongly linked to oropharyngeal cancers.

• Occupational exposure – long-term exposure to harmful substances such as asbestos [6], wood dust [7], and certain industrial chemicals [8] or formaldehyde can elevate the risk of developing cancers in the nasal cavity, sinuses or throat.

How are head and neck cancers diagnosed?

When it comes to diagnosing Head and Neck cancer, the diagnostic procedure typically begins with a thorough examination:

• Imaging tests – imaging tests are advanced imaging techniques, such as computerised tomography (CT) scan, magnetic resonance imaging (MRI), and positron emission tomography (PET) scan. It is used to pinpoint the exact location, size, and spread of the tumours, providing crucial information for staging, and treatment planning.

• Biopsies – biopsies are the gold standard for diagnosis. It involves taking a small tissue sample from the suspected area for microscopic examination. There are three different types of biopsies, which are fine-needle aspiration, core biopsy, and surgical biopsy.

• Endoscopic procedure – endoscopic procedures are minimally invasive techniques, which allow Head & Neck specialists direct visualisation of affected areas using specialised instruments. Some of these instruments include nasoendoscopes or laryngoscpes, which are used to assess the extent of the disease.

What are the stages of head and neck cancer?

Understanding the stage of head and neck cancer is crucial for both diagnosis, and treatment planning. It provides insight into how far the cancer has spread, and helps guide the next steps in your care. Head and neck cancers are classified into five stages, starting at Stage 0, and progressing to Stage IV.

• Stage 0 (Carcinoma in Situ) – stage 0 is the earliest stage. It indicates abnormal cells in the lining of the affected area. While not yet invasive, these cells have the potential to develop into cancer.

• Stage I – stage I is an early-stage cancer, where the tumour is small, measuring no more than 2 centimeters. At this stage, the cancer has not spread to the lymph nodes.

• Stage II – stage II describes a tumour larger than 2 centimeters, but not exceeding 4 centimeters. Like stage I, the cancer remains localised, and has not reached the lymph nodes.

• Stage III – stage III indicates the tumour may exceed 4 centimeters or have spread to a single lymph node on the same side of the neck as the tumour. The affected lymph node will measure less than 3 centimeters in size.

• Stage IV – stage IV is the most advanced stage, and indicates that the cancer has spread extensively. It may involve nearby tissues, multiple lymph nodes or even distant organs like the lungs. The subcategories of stage IV are:

• Localised – localised spread to tissues in the head and neck.
• Lymph node involvement – this involves one large node or multiple nodes on the same or opposite side of the neck.
• Metastasis – this refers to where the cancer has spread to distant parts of the body.

Treatment Options for Head and Neck Cancer

Once the Head & Neck specialist has confirmed a diagnosis, and determined the characteristics of the tumour, which includes its staging, they will proceed to outline a treatment plan. Depending on how advanced the staging is, treatment may involve a standalone treatment plan or a combination of multiple treatments to better improve the outcomes. 

Primary treatment

• Chemotherapy – chemotherapy is a systemic treatment using potent drugs to kill or slow the growth of cancer cells. While it can be prescribed as a standalone treatment, it is typically combined with radiotherapy for advanced-stage cancers.
• Radiotherapy – radiotherapy uses high-energy radiation to precisely target, and destroy cancer cells while sparing surrounding healthy tissue. It is often used alone or in combination with other treatments.
• Surgery – surgical removal of tumours, and affected tissues is often the first-line of treatment for localised cancers. The procedures may range from minimally invasive techniques to more extensive surgeries, such as neck dissections. However, this will depend on the size, and location of the tumour.

Advanced therapies

• Immunotherapy – immune is a cutting-edge approach that harnesses the body’s immune system to identify, and attack cancer cells. The treatment often offers hope for advanced or recurrent cancers.
• Targeted therapy – targeted therapy involves the use of innovative drugs that specifically target molecular pathways, which are critical for cancer cell survival, and proliferation. As a result, it minimises damage to normal cells.

Rehabilitation

One of the key aspects of treatment for head and neck cancer is rehabilitation. It is essential for improving quality of life post-treatment. This may include:

• Speech therapy – speech therapy helps patients regain communication skills, particularly after surgeries that affect the vocal cords or throat.
• Swallowing therapy – swallowing therapy addresses difficulties with eating, and drinking, which are often caused by tumour removal or radiation.
• Nutritional support - nutritional support are tailored plans to maintain strength, and support healing during, and after the treatment.

Can head and neck cancers be prevented?

It should be emphasised that head and neck cancer is a highly preventable disease. Preventing head and neck cancer requires a proactive approach to health, and lifestyle choices. While some risk factors, like genetics, cannot be controlled, many can be addressed through informed decisions, and preventive measures. By understanding these steps, it will empower individuals to reduce their risk, and improve their overall well-being.

Avoiding tobacco and excessive alcohol use

The use of tobacco, and excessive alcohol consumption are the leading preventable risk factors for head and neck cancers. Smoking, chewing tobacco, and prolonged alcohol use damage cells in the mouth, throat, and nearby tissues, significantly increasing cancer risk.  By eliminating tobacco, and moderating alcohol intake, it will undoubtedly set you on the path towards prevention.

Speaking of the path towards prevention, support programmes such as nicotine replacement therapies, and counselling can provide essential tools to help individuals quit. Similarly, reducing alcohol consumption through moderation strategies or support groups can also contribute to lower cancer risk, and overall better health.

HPV Vaccination

HPV is a major cause [9] of oropharyngeal cancers. As such, vaccination against HPV is a proven preventive measure, particularly for younger individuals as it helps protect against the strains of the virus that are commonly associated with cancer. Widespread vaccination programmes have shown promising results in reducing cancer incidence rates in both men, and women.

Regular Medical Check-ups

The primary step to lowering your risk of developing cancer is to undergo routine medical examinations, and screenings. This is due to the fact that both are indispensable for early detection, especially for individuals at high risk due to lifestyle choices, family history or occupational exposure. Regular check-ups with a healthcare provider enable doctors to identify any abnormal changes in the head and neck region before they progress into more severe conditions.

Remember; early detection often leads to more effective treatment, fewer complications, and better treatment outcomes. Medical screenings, such as visual inspections, imaging tests, and biopsies, play critical roles in diagnosing cancers at an early stage, particularly when they are most treatable.

Summary 

In a nutshell, proactive health measures and awareness can make a significant difference in preventing head and neck cancers. In addition, recognising the symptoms early, such as persistent hoarseness, unexplained lumps or difficulty swallowing, combined with timely medical advice, are vital steps to safeguarding your health against head and neck cancers. By taking preventative actions, and making informed lifestyle changes, you can reduce your risk of developing the disease, and ensure a healthier future.

Schedule a consultation with us today for a comprehensive diagnosis and personalised treatment plan.

References

[1]  Head and Neck Cancer: Symptoms and Risk Factors - HealthXchange. (n.d.). In www.healthxchange.sg. Retrieved January 22, 2025, from https://www.healthxchange.sg/cancer/head-neck-cancer/head-neck-cancer-symptoms-risk-factors

[2] Freedman ND, Schatzkin A, Leitzmann MF, Hollenbeck AR, Abnet CC. Alcohol and head and neck cancer risk in a prospective study. Br J Cancer. 2007 May 7;96(9):1469-74. doi: 10.1038/sj.bjc.6603713. Epub 2007 Mar 27. PMID: 17387340; PMCID: PMC2360181.

[3] Jethwa AR, Khariwala SS. Tobacco-related carcinogenesis in head and neck cancer. Cancer Metastasis Rev. 2017 Sep;36(3):411-423. doi: 10.1007/s10555-017-9689-6. PMID: 28801840; PMCID: PMC5709040.

[4] Li X, Koskinen AI, Hemminki O, Försti A, Sundquist J, Sundquist K, Hemminki K. Family History of Head and Neck Cancers. Cancers (Basel). 2021 Aug 16;13(16):4115. doi: 10.3390/cancers13164115. PMID: 34439270; PMCID: PMC8392405.

[5] Galati L, Chiocca S, Duca D, Tagliabue M, Simoens C, Gheit T, Arbyn M, Tommasino M. HPV and head and neck cancers: Towards early diagnosis and prevention. Tumour Virus Res. 2022 Dec;14:200245. doi: 10.1016/j.tvr.2022.200245. Epub 2022 Aug 13. PMID: 35973657; PMCID: PMC9420391.

[6] Clin B, Gramond C, Thaon I, Brochard P, Delva F, Chammings S, Gislard A, Laurent F, Paris C, Lacourt A, Pairon JC. Head and neck cancer and asbestos exposure. Occup Environ Med. 2022 Oct;79(10):690-696. doi: 10.1136/oemed-2021-108047. Epub 2022 Apr 7. PMID: 35393288; PMCID: PMC9484389.

[7] Langevin SM, McClean MD, Michaud DS, Eliot M, Nelson HH, Kelsey KT. Occupational dust exposure and head and neck squamous cell carcinoma risk in a population-based case-control study conducted in the greater Boston area. Cancer Med. 2013 Dec;2(6):978-86. doi: 10.1002/cam4.155. Epub 2013 Nov 4. PMID: 24403272; PMCID: PMC3892403.

[8] Carton M, Barul C, Menvielle G, Cyr D, Sanchez M, Pilorget C, Trétarre B, Stücker I, Luce D; ICARE Study Group. Occupational exposure to solvents and risk of head and neck cancer in women: a population-based case-control study in France. BMJ Open. 2017 Jan 9;7(1):e012833. doi: 10.1136/bmjopen-2016-012833. PMID: 28069619; PMCID: PMC5223686.

[9] Chaturvedi, A. K., Freedman, N. D., & Abnet, C. C. (2022). The Evolving Epidemiology of Oral Cavity and Oropharyngeal Cancers. Cancer research, 82(16), 2821–2823. https://doi.org/10.1158/0008-5472.CAN-22-2124

Our skin is the body’s largest organ, serving as a vital barrier that protects us from harsh external elements. However, like any other organ, it is susceptible to disease, like skin cancer, with ultraviolet (UV) radiation being the leading cause. In sunny Singapore, our risk is heightened due to this year-round sun exposure.

The good news is that skin cancer is also one of the most preventable types of cancer. By adopting simple protective measures and going for regular skin checks for suspicious moles, your risk of developing skin cancer can be significantly reduced. Early detection is also key to ensuring successful treatment, and in many cases, skin cancer can be treated with minimal intervention if caught early enough. 

This begs the question: how can I tell the difference between a harmless mole and a cancerous growth? In this article, we’ll talk about what to look out for, when to visit a doctor, and the treatment options available. 

What is skin cancer?

Skin cancer occurs when abnormal skin cells grow uncontrollably, often triggered by ultraviolet (UV) radiation [3] from the sun or tanning beds. This cell proliferation can lead to tumours, both benign and malignant. While some types of skin cancer remain localised, others can spread to other parts of the body, making early detection crucial.

Melanoma are the most dangerous type of skin cancer, and can develop from existing moles or as new, abnormal growths. Unlike other types of skin cancers, it spreads quickly to other organs if not treated promptly. 

Three main types of skin cancer:

• Basal Cell Carcinoma (BCC) – BCC [4] is the most common, and least aggressive form of skin cancer. It rarely spreads but can cause damage to surrounding tissues if it is left untreated.

• Squamous Cell Carcinoma (SCC) – SCC [5], on the other, is more aggressive than BCC, and can spread to other parts of the body. However, early treatment typically offers a high cure rate.

• Melanoma – melanoma [6] is the most dangerous form of skin cancer. It spreads rapidly, and can be fatal if it is not detected, and treated early.

What are the risk factors for skin cancer?

The risk factors for skin cancer include:

• Age – while skin cancer can affect anyone at any age, people who are aged 50 years old [7], and older are more susceptible to developing the disease.

• Atypical moles – people with atypical moles [8], which are large, uneven, and asymmetrical, are at a higher risk of developing skin cancer.

• Family history – a family history [9] of skin cancer increases your susceptibility of developing skin cancer in your lifetime.

• History of sunburns – repeated sunburns [10] in childhood or adolescence can significantly increase the risk of developing skin cancer later in life.

• Medical history – people with a prior diagnosis of skin cancer [11] or certain human papillomavirus (HPV) conditions [12] have a higher risk of developing the disease.

• Skin type – skin cancer is more common among people with fair skin [13], freckles or a tendency to burn easily.

• Smoking – smoking [14] increases the risk of developing SCC, particularly around the lips.

• UV exposure – people who are frequently exposed to UV radiation, either from the sun or tanning beds [15], have an elevated risk of developing skin cancer.

Recognising potential red flags: Is It a mole or skin cancer?

One of the key steps to prevent skin cancer is to regularly monitor the appearance of your moles. It helps to take photographs of any suspicious moles — this helps you monitor any changes, and would come in handy during your consultation with your doctor.

The ABCDE rule

(A)symmetry	Cancerous moles tend to have irregular shapes, whole benign moles are usually symmetrical.
(B)order	Normal moles have smooth, well-defined borders, while moles that are irregular or jagged may be suspicious.
(C)olour	Benign moles are usually one uniform colour. Skin cancer, however, may have several shades, including red, black, blue or white.
(D)iametre	Moles that are larger than six millimetre should be examined further. Be that as it may, skin cancer can also appear in smaller moles.
(E)volving	Moles that change in colour, shape, size or texture should be monitored closely as it can indicate skin cancer.

Additional signs to take note of 

On top of the ABCDE rule, it is advisable to look out for these additional symptoms:

• Bleeding – moles that bleed, ooze or form scabs can be indicative of skin cancer.

• Itching – skin cancer moles may itch, hurt or feel tender, unlike typical, and harmless moles.

• New mole growths – the development of new moles, particularly after the age 30 years old, should be taken seriously.

How is skin cancer diagnosed?

When it comes to skin cancer, early detection can make all the difference in the success of the treatment. While self-examinations are crucial for spotting any suspicious changes, there may come a time when you need the expertise of a professional to assess your moles or skin lesions more thoroughly. Certain diagnostic tests can be performed by your doctor, such as:

Dermoscopy

One of the most valuable tools in a specialists’ toolkit is dermoscopy. Dermoscopy is a non-invasive technique that allows specialists to magnify, and examine moles in greater detail. Using a dermoscope, which is a handheld device equipped with a magnifying lens and light source, specialists can closely inspect the mole’s structure, including the pattern of pigment, and blood vessels within the skin.

This magnified view helps specialists to assess whether a mole exhibits characteristics that suggest malignancy, such as irregular borders, multiple colours or asymmetry. Dermoscopy enables specialists to identify subtle changes that might not be visible to the naked eye, offering a more accurate assessment of whether a mole is benign or potentially malignant.

Skin Biopsy

If a mole is deemed suspicious after a physical examination or dermoscopy, a skin biopsy may be performed. A biopsy is the definitive way to determine whether a mole is benign or malignant, making it the ideal test for diagnosing skin cancer.

The biopsy involves removing a small sample of tissue from the mole or growth, which is then sent to a laboratory for microscopic examination. Depending on the size, and location of the mole, there are different types of skin biopsies that may be used:

• Shave biopsy – a small portion of the surface of the mole is shaved off.
• Punch biopsy – a circular tool is used to remove a deeper, more extensive tissue sample.
• Excisional biopsy – the entire mole or growth is removed, including a small margin of healthy skin around it.

The biopsy results will confirm whether the mole is benign or if it contains cancerous cells. If cancer is detected, the specialist will discuss appropriate treatment options based on the type, size, and stage of the cancer.

Treatment options for skin cancer

Treatment options for skin cancer depend heavily on the type, stage, and location of the cancer, as well as the overall health of the individual. The treatment options range from minor surgical procedures to more complex therapies. Each approach is designed to remove or destroy cancerous cells while minimising damage to surrounding healthy tissue to ensure all cancer cells are eradicated. 

Surgical Removal

Surgical removal is the most common treatment for skin cancer. The procedure involves removing the cancerous tissue from the skin, along with a small margin of surrounding healthy tissue to ensure all cancer cells are eradicated. For less invasive cases, on the other hand, simple excision – which involves cutting out the cancer – may be sufficient.

However, for more intricate cases, such as melanoma or BCC, Mohs surgery is often recommended.

It is a highly effective technique that involves the meticulous removal of thin layers of skin, examining each layer for cancer cells as the procedure progresses. This method offers high precision, and ensures that only the affected tissue is removed, preserving as much healthy skin as possible. Mohs surgery is particularly effective for skin cancers in areas where tissue preservation is important, such as the face.

Radiation Therapy and Chemotherapy

When skin cancer has spread beyond its original site, or if it is in a location that is difficult to treat surgically, radiation therapy may be used. Radiation therapy involves using high-energy rays to destroy cancer cells. It can be used for skin cancers that are hard to reach surgically or when surgery is not an option. 

Chemotherapy, while more commonly associated with other types of cancer, may be used for advanced skin cancers that have spread to other parts of the body. Chemotherapy drugs target, and destroy cancer cells throughout the body, often through intravenous or oral medication. While chemotherapy can be effective in treating skin cancer that has metastasised, it is typically reserved for more aggressive cases of melanoma.

Immunotherapy

Immunotherapy is an emerging treatment, particularly for melanoma, that works by enhancing the body’s immune system to target and fight cancer cells. It uses drugs that stimulate the immune system to recognise, and attack cancer cells, even in advanced stages. The therapy has shown promising results for patients with metastatic melanoma, offering hope for individuals with cancers that are resistant to traditional treatments.

Protecting your skin from skin cancer

While skin cancer is highly treatable, prevention remains the most effective way to reduce the risk of developing it in the first place. By making small adjustments to your daily habits, you can significantly lower your chances of developing skin cancer. 

Sunscreen is your first line of defence

One of the simplest, and most effective ways to protect your skin from skin cancer is by using sunscreen. Broad-spectrum sunscreen with an SPF of 40 or higher offers protection from both UVA, and UVB rays [20], which are the primary cause of skin damage, and cancer. It is important to reapply sunscreen every two hours, especially if you are sweating or swimming, as water, and perspiration can wash it away. Do not forget areas like your ears, back of the neck, and under your chin, which are often overlooked.

Wear protective clothing

In addition to sunscreen, wearing protective clothing can provide an extra layer of defence against the sun. Wide-brimmed hats, sunglasses, and long sleeves offer physical protection by shielding your skin from direct UV rays. Opt for clothing with an Ultraviolet Protection Factor (UPF) rating for additional sun protection. Avoiding the sun during peak hours,  typically between 10 am, and 4 pm, is another simple way to reduce your exposure. 

Avoid tanning beds

While tanning beds may seem like a quick way to achieve a sun-kissed glow, they come with significant risks. Tanning beds emit harmful UV rays that can cause skin damage, and increase your risk of developing skin cancer, particularly melanoma. The World Health Organisation (WHO) has classified tanning beds as a Group 1 carcinogen, meaning they are known to cause cancer. 

Go for regular skin checks

Regular visits to a specialist for a skin checkup are an essential part of early detection. Specialists are trained to spot suspicious moles, and lesions that may not be visible or noticeable to the untrained eye. If you are at higher risk, annual skin checks are strongly recommended. Even if you are not at high risk, seeing a specialist for regular checkups can help ensure any potential issues are caught early, when treatment is most effective.

Summary

Skin cancer is highly preventable, and treatable, especially when caught early. Early detection through regular skin checks is the key to successful outcomes — and this starts with prevention and being mindful of your body and the changes in your skin.

It’s important to remember that no concern is too small. If you experience a suspicious mole or skin change, schedule an appointment with us today for a thorough skin assessment and ensure your peace of mind. 

References

[1] Oh CC, Jin A, Koh WP. Trends of cutaneous basal cell carcinoma, squamous cell carcinoma, and melanoma among the Chinese, Malays, and Indians in Singapore from 1968-2016. JAAD Int. 2021 Jun 30;4:39-45. doi: 10.1016/j.jdin.2021.05.006. PMID: 34409390; PMCID: PMC8361884.

[2] Common Types of Cancer in Singapore. (n.d.). In www.singaporecancersociety.org.sg. Retrieved January 21, 2025, from https://www.singaporecancersociety.org.sg/learn-about-cancer/cancer-basics/common-types-of-cancer-in-singapore.html

[3] Kim Y, He YY. Ultraviolet radiation-induced non-melanoma skin cancer: Regulation of DNA damage repair and inflammation. Genes Dis. 2014 Dec 1;1(2):188-198. doi: 10.1016/j.gendis.2014.08.005. PMID: 25642450; PMCID: PMC4307792.

[4] Kasumagic-Halilovic E, Hasic M, Ovcina-Kurtovic N. A Clinical Study of Basal Cell Carcinoma. Med Arch. 2019 Dec;73(6):394-398. doi: 10.5455/medarh.2019.73.394-398. PMID: 32082007; PMCID: PMC7007603.

[5] Combalia A, Carrera C. Squamous Cell Carcinoma: An Update on Diagnosis and Treatment. Dermatol Pract Concept. 2020 Jun 29;10(3):e2020066. doi: 10.5826/dpc.1003a66. PMID: 32642314; PMCID: PMC7319751.

[6] Melanoma Skin Cancer Research. (n.d.). In Melanoma Studies. Retrieved January 21, 2025, from https://www.cancer.org/cancer/types/melanoma-skin-cancer/about/new-research.html

[7] Skin Cancer Facts & Statistics. (n.d.). In The Skin Cancer Foundation. Retrieved January 21, 2025, from https://www.skincancer.org/skin-cancer-information/skin-cancer-facts/

[8] Wensley KE, Zito PM. Atypical Mole. [Updated 2023 Jul 3]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK560606/

[9] Asgari MM, Warton EM, Whittemore AS. Family history of skin cancer is associated with increased risk of cutaneous squamous cell carcinoma. Dermatol Surg. 2015 Apr;41(4):481-6. doi: 10.1097/DSS.0000000000000292. PMID: 25760557; PMCID: PMC5758040.

[10] Lergenmuller, S., Rueegg, C. S., Perrier, F., Robsahm, T. E., Green, A. C., Lund, E., Ghiasvand, R., & Veierd, M. B. (2022). Lifetime Sunburn Trajectories and Associated Risks of Cutaneous Melanoma and Squamous Cell Carcinoma Among a Cohort of Norwegian Women. In JAMA Dermatology (Vol. 158, Issue 12, p. 1367). American Medical Association (AMA). https://doi.org/10.1001/jamadermatol.2022.4053

[11] Toro JR, Blake PW, Björkholm M, Kristinsson SY, Wang Z, Landgren O. Prior history of non-melanoma skin cancer is associated with increased mortality in patients with chronic lymphocytic leukemia. Haematologica. 2009 Oct;94(10):1460-4. doi: 10.3324/haematol.2008.004721. PMID: 19794092; PMCID: PMC2754966.

[12] Chen ML, Wang SH, Wei JC, Yip HT, Hung YM, Chang R. The Impact of Human Papillomavirus Infection on Skin Cancer: A Population-Based Cohort Study. Oncologist. 2021 Mar;26(3):e473-e483. doi: 10.1002/onco.13593. Epub 2020 Dec 8. PMID: 33191546; PMCID: PMC7930420.

[13] Goon P, Banfield C, Bello O, Levell NJ. Skin cancers in skin types IV-VI: Does the Fitzpatrick scale give a false sense of security? Skin Health Dis. 2021 Jun 8;1(3):e40. doi: 10.1002/ski2.40. PMID: 35663142; PMCID: PMC9060139.

[14] De Hertog SA, Wensveen CA, Bastiaens MT, Kielich CJ, Berkhout MJ, Westendorp RG, Vermeer BJ, Bouwes Bavinck JN; Leiden Skin Cancer Study. Relation between smoking and skin cancer. J Clin Oncol. 2001 Jan 1;19(1):231-8. doi: 10.1200/JCO.2001.19.1.231. PMID: 11134217.

[15] Schulman JM, Fisher DE. Indoor ultraviolet tanning and skin cancer: health risks and opportunities. Curr Opin Oncol. 2009 Mar;21(2):144-9. doi: 10.1097/CCO.0b013e3283252fc5. PMID: 19532016; PMCID: PMC2913608.

[16] Hall KH, Rapini RP. Acral Lentiginous Melanoma. [Updated 2023 Jul 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK559113/

[17] Bhatt M, Nabatian A, Kriegel D, Khorasani H. Does an increased number of moles correlate to a higher risk of melanoma? Melanoma Manag. 2016 Jun;3(2):85-87. doi: 10.2217/mmt-2016-0001. Epub 2016 May 19. PMID: 30190875; PMCID: PMC6096442.

[18] Toffoli L, Dianzani C, Bonin S, Guarneri C, Guarneri F, Giuffrida R, Zalaudek I, Conforti C. Actinic Keratoses: A Prospective Pilot Study on a Novel Formulation of 4% 5-Fluorouracil Cream and a Review of Other Current Topical Treatment Options. Cancers (Basel). 2023 May 28;15(11):2956. doi: 10.3390/cancers15112956. PMID: 37296918; PMCID: PMC10251935.

[19] Paul SP. Melanoma arising after imiquimod use. Case Rep Med. 2014;2014:267535. doi: 10.1155/2014/267535. Epub 2014 Nov 9. PMID: 25431597; PMCID: PMC4241307.

[20] Sander M, Sander M, Burbidge T, Beecker J. The efficacy and safety of sunscreen use for the prevention of skin cancer. CMAJ. 2020 Dec 14;192(50):E1802-E1808. doi: 10.1503/cmaj.201085. PMID: 33318091; PMCID: PMC7759112.

The Salivary Glands: for Digestion, Lubrication and Oral Health

Salivary glands play a crucial role in our day-to-day lives, often without us realising it. These glands produce saliva, a vital fluid that aids digestion, protects teeth from decay, and keeps the mouth moist, enabling us to speak, swallow, and taste comfortably. The major salivary glands — parotid, submandibular, and sublingual — are located around the face and jaw, while hundreds of minor salivary glands are scattered across the lips, cheeks, and throat. 

Like any part of the body, salivary glands can develop problems, with tumours being one of the most significant concerns. While salivary gland tumours are relatively rare, they are a cause for attention as they can range from benign (non-cancerous) to malignant (cancerous) [1]. Among these, parotid gland tumours are the most common, but tumours can also occur in the submandibular, sublingual, or minor salivary glands.

Understanding the differences between parotid tumours and those in other salivary glands is vital for early recognition, diagnosis, and treatment. This blog will explore the distinctions, shedding light on their prevalence, symptoms, and management, so you can gain clarity on this often-overlooked area of health. Whether you are seeking knowledge for yourself or a loved one, knowing these differences can make all the difference in addressing salivary gland tumours effectively.

What Are the Different Types of Salivary Glands?

The salivary glands are a network of glands responsible for producing and secreting saliva, a fluid essential for digestion, oral hygiene, and overall mouth comfort. These glands are categorised into major salivary glands and minor salivary glands, each playing a specific role in saliva production.

1. Parotid Glands

The parotid glands are the largest of the salivary glands and are located on either side of the face, just in front of and below the ears [2]. Each parotid gland secretes saliva into the mouth through the parotid duct (Stensen’s duct), which opens near the upper second molar. Parotid glands primarily produce a watery, enzyme-rich saliva that aids in breaking down food during digestion. Given their size and location, parotid glands are the most common site for salivary gland tumours.

2. Submandibular Glands

Positioned beneath the lower jaw, or mandible, the submandibular glands are the second-largest salivary glands [3]. They produce a mix of watery and mucous saliva, contributing to both lubrication and digestion. Saliva from the submandibular glands is transported into the mouth through the submandibular duct (Wharton’s duct), which opens into the floor of the mouth. Tumours in these glands are less frequent than in the parotid but tend to have a higher likelihood of malignancy.

3. Sublingual Glands

The smallest of the major salivary glands, the sublingual glands are located beneath the tongue, in the floor of the mouth. Unlike the parotid and submandibular glands, these glands produce saliva that is primarily mucous in consistency. Saliva from the sublingual glands is secreted through several small ducts (Rivinus ducts) that open directly into the mouth. Tumours in the sublingual glands are rare but often more likely to be cancerous.

4. Minor Salivary Glands

In addition to the major salivary glands, there are numerous minor salivary glands—between 600 to 1,000 — spread throughout the oral cavity and throat [4]. These small glands are located in the lips, cheeks, palate, and the lining of the throat (pharynx). Unlike the major salivary glands, minor glands do not have a single large duct but release saliva directly into the oral cavity through tiny openings. Though minor salivary gland tumours are uncommon, they are more likely to be malignant when they do occur.

Each type of gland has its unique structure and function, but all are integral to maintaining oral and digestive health.

How Common Are Tumours in Salivary Glands, and Which Glands Are Most Affected?

Salivary gland tumours are uncommon, but their prevalence and malignancy rates differ based on the specific gland affected. The parotid gland is the most frequent site for these tumours, with a high percentage being benign. 

Conversely, smaller glands such as the sublingual and minor salivary glands carry a significantly higher risk of malignancy. Understanding the distribution and nature of these tumours is key to early detection and effective management. The following table summarises the prevalence and malignancy rates across the different salivary glands [5]: 

Salivary Gland	Percentage of Tumours	Commonality	Benign Tumours (%)	Malignant Tumours (%)
Parotid Gland	80%	Most common	75-80%	20-25%
Submandibular Gland	10-15%	Less common	50-60%	40-50%
Sublingual Gland	<1%	Very rare	10-30%	70-90%
Minor Salivary Glands	10-15%	Scattered in the oral cavity	25-50%	50-75%

Early detection and medical evaluation are especially critical when tumours arise in smaller glands, as the risk of malignancy is higher.

What Are the Most Common Types of Parotid Tumours?

The parotid glands are the largest salivary glands and the most common site for salivary gland tumours, accounting for around 80% of cases. While most parotid gland tumours are benign, a small percentage can be malignant. Understanding the types of tumours that occur in the parotid glands helps clarify their nature, symptoms, and treatment approaches.

Common Benign Parotid Tumours

Pleomorphic Adenoma

• Pleomorphic adenoma, also known as a benign mixed tumour, is the most common type of parotid gland tumour [6].
• It grows slowly, is usually painless, and feels firm or rubbery upon examination.
• Though benign, it can become large if left untreated and carries a small risk of malignant transformation over time. Surgical removal is the standard treatment.

Warthin’s Tumour

• Warthin’s tumour, or papillary cystadenoma lymphomatosum, is the second most common benign parotid tumour [7].
• It is more frequently observed in middle-aged or older individuals and has a strong association with smoking.
• Warthin’s tumours are typically painless and may occur bilaterally (on both sides) in about 7% to 10% of cases [8]. Surgical excision is usually sufficient for treatment.

Common Malignant Parotid Tumours

Mucoepidermoid Carcinoma

• Mucoepidermoid carcinoma is the most common malignant tumour in the parotid gland [9].
• It can range from low-grade (slow-growing, less aggressive) to high-grade (fast-growing, invasive) forms.
• Symptoms may include a growing mass, pain, and sometimes facial nerve weakness if the tumour affects surrounding structures. Treatment often involves surgery, sometimes followed by radiation therapy.

Acinic Cell Carcinoma

• Acinic cell carcinoma is another type of malignant tumour that primarily affects the parotid gland [10].
• It tends to grow slowly and may initially appear similar to a benign tumour.
• Although less aggressive than other malignant tumours, it can recur after removal, particularly if not completely excised [11]. Surgery is the primary treatment, with close follow-up to monitor for recurrence.

The parotid gland’s anatomical location near the facial nerve makes surgical management of these tumours complex. For both benign and malignant tumours, accurate diagnosis through imaging and biopsy is crucial to determine the best course of action. Understanding the differences between tumour types can help ensure timely and appropriate treatment, improving patient outcomes.

How are Parotid Tumours and Other Salivary Gland Tumours different?

Factor	Parotid Tumours	Other Salivary Gland Tumours
Location and Anatomy	It is the largest salivary gland, and can be found near the jaw and ear.	Submandibular: under the jawSublingual: under the tongueMinor glands: scattered around the mouth and throat
Prevalence and Malignancy rates	Most are benign	Higher malignancy rates
Symptoms	Painless swelling	Pain, difficulty swallowing, speech changes in its later stages
Treatment	Surgery, radiation or chemotherapy in some cases	Surgery, radiation or chemotherapy in some cases

What Types of Tumours Occur in Submandibular, Sublingual, and Minor Salivary Glands?

While parotid gland tumours are the most common, tumours in the submandibular, sublingual, and minor salivary glands are less frequent but carry a higher risk of malignancy. These glands are smaller and more anatomically dispersed, which often contributes to the aggressive nature of the tumours found in these locations.

Submandibular Gland Tumours

• The submandibular glands, located beneath the lower jaw, account for approximately 10-15% of all salivary gland tumours [12].
• Compared to the parotid glands, tumours in the submandibular glands have a higher likelihood of malignancy, with up to 40-50% being cancerous.
• Common benign tumours include pleomorphic adenoma, similar to those found in the parotid glands. However, malignant tumours are more frequently observed and include:
  • Adenoid Cystic Carcinoma: A slow-growing but aggressive cancer that tends to invade nerves and nearby tissues, often recurring even after treatment [13].
  • Mucoepidermoid Carcinoma: Can range from low-grade (less aggressive) to high-grade (more invasive) [14].

Sublingual Gland Tumours

• The sublingual glands, located beneath the tongue, are the smallest of the major salivary glands. Tumours here are extremely rare, representing less than 1% of all salivary gland tumours [15].
• Despite their rarity, sublingual gland tumours have a very high malignancy rate—up to 70-90% are cancerous [16].
• Malignant tumours typically include:
  • Adenoid Cystic Carcinoma: Known for its slow progression but persistent recurrence and nerve invasion.
  • Mucoepidermoid Carcinoma: Although less common here, it remains a serious malignancy requiring prompt treatment.

Minor Salivary Gland Tumours

• Minor salivary glands are scattered throughout the oral cavity, including the lips, cheeks, palate, throat, and even the nasal passages. Tumours in these glands make up approximately 10-15% of all salivary gland tumours [17].
• Like sublingual gland tumours, those in the minor salivary glands have a higher likelihood of malignancy, with about 50-75% being cancerous [18].
• Common tumour types include:
  • Adenoid Cystic Carcinoma: The most frequent malignant tumour in minor salivary glands, characterised by nerve involvement and slow but relentless growth [19].
  • Polymorphous Low-Grade Adenocarcinoma: A slow-growing malignancy typically found on the palate, with an excellent prognosis when detected early [20].
  • Mucoepidermoid Carcinoma: Also observed in the minor glands, varying in severity depending on tumour grade [21].

Tumours in the submandibular, sublingual, and minor salivary glands often present later than parotid tumours, as they can be harder to detect early due to their location and smaller size. This late detection, combined with a higher risk of malignancy, makes early diagnosis and treatment critical. 

What Are the Symptoms of Salivary Gland Tumours?

Salivary gland tumours can present with various symptoms, depending on the gland involved and whether the tumour is benign or malignant. Below are the most common symptoms to watch for:

• Lump or swelling near the jawline, in front of the ear, beneath the jaw, or inside the mouth.
• Facial numbness or weakness, particularly when the tumour presses on or invades the facial nerve.
• Pain or discomfort that may worsen over time, especially with rapidly growing tumours.
• Difficulty swallowing or speaking, often seen with tumours in the submandibular, sublingual, or minor salivary glands.
• Dry mouth or reduced saliva flow, leading to altered taste or difficulty chewing.

These symptoms can vary depending on the location of the tumour, but any persistent lump, pain, or functional issue should be assessed by a medical professional for proper diagnosis and treatment.

How Are Salivary Gland Tumours Diagnosed?

Diagnosing salivary gland tumours involves a combination of clinical evaluation, imaging studies, and tissue sampling to determine the tumour's nature. A thorough diagnostic approach is essential to differentiate between benign and malignant tumours and to plan appropriate treatment.

Physical Examination and Medical History

The diagnostic process begins with a detailed physical examination and discussion of the patient’s medical history. During the examination, the doctor:

• Feels for lumps or swelling near the jaw, under the chin, or inside the mouth.
• Checks for tenderness, firmness, or irregularities in the lump.
• Assesses for any signs of facial weakness, asymmetry, or numbness, which may indicate nerve involvement.

A review of symptoms such as pain, swallowing difficulties, or saliva changes, along with factors like smoking history or prior radiation exposure, helps guide further evaluation.

Imaging Studies

Imaging techniques are essential to determine the size, location, and extent of the tumour, as well as its impact on nearby structures. The most common imaging methods include:

Magnetic Resonance Imaging (MRI):

• Provides detailed images of soft tissues, making it ideal for assessing salivary gland tumours.
• Helps distinguish between benign and malignant tumours based on size, margins, and tissue characteristics.

Computed Tomography (CT) Scans:

• Offers cross-sectional images to evaluate the tumour’s size, location, and involvement of adjacent bones or tissues.
• Useful for detecting any signs of tumour spread to lymph nodes or other areas.

In some cases, an ultrasound may also be used as a non-invasive method to assess the lump and guide biopsy procedures.

Fine-Needle Aspiration Biopsy (FNAB)

A fine-needle aspiration biopsy is the gold standard for determining the nature of a salivary gland tumour. This minimally invasive procedure involves:

• Using a thin, hollow needle to extract a small tissue or cell sample from the tumour.
• Sending the sample to a laboratory for cytological analysis to identify whether the tumour is benign or malignant.

FNAB is generally safe, quick, and well-tolerated by patients. It provides valuable information that aids in diagnosis and helps guide treatment decisions, such as whether surgical removal is necessary.

By combining physical examination, imaging techniques, and fine-needle aspiration biopsy, healthcare professionals can accurately diagnose salivary gland tumours. Early and precise diagnosis is key to ensuring effective treatment and improving patient outcomes.

What Are the Treatment Options for Salivary Gland Tumours?

The treatment of salivary gland tumours primarily depends on whether the tumour is benign or malignant, its location, and its stage. Surgical removal remains the cornerstone of treatment, but additional therapies may be required for malignant cases to ensure optimal outcomes.

Surgical Removal

Surgery is the primary treatment for both benign and malignant salivary gland tumours.

• For benign tumours, surgery typically involves removing the tumour while preserving as much of the surrounding healthy tissue as possible.
• For malignant tumours, the goal is to remove the tumour entirely, sometimes along with affected lymph nodes to prevent further spread.

In parotid gland tumours, special care is taken due to the facial nerve running through the gland. Surgeons aim to preserve the nerve’s function while ensuring complete tumour excision. In some cases, nerve grafting or reconstructive procedures may be required if the tumour has invaded the nerve.

Radiation Therapy

Radiation therapy is often used as an additional treatment for malignant tumours, especially if:

• The tumour cannot be completely removed surgically.
• Cancer has spread to surrounding tissues or lymph nodes.
• It works by using high-energy rays to destroy residual cancer cells, reducing the risk of recurrence.

Chemotherapy

• Chemotherapy may be considered in advanced or metastatic salivary gland cancers where the tumour has spread beyond its original site.
• While not always the first-line treatment, it can be used alongside radiation therapy to improve outcomes in aggressive cases.

Prognosis and Outcomes

The prognosis for salivary gland tumours varies based on the tumour type, stage, and how early it is detected:

Benign Tumours:

• Generally, the prognosis is excellent after complete surgical removal.
• Recurrence is rare but may occur if the tumour is not entirely excised.

Malignant Tumours:

Several factors influence the prognosis, including:

• Tumour Grade and Stage: Low-grade tumours tend to grow slowly and have a better prognosis, while high-grade tumours are more aggressive and carry higher risks of recurrence and spread.
  
• Early Detection and Treatment: Early diagnosis significantly improves outcomes, as malignant tumours are more treatable when localised.

For parotid gland malignancies, the proximity to the facial nerve may complicate surgery and affect outcomes. However, advancements in surgical techniques and post-operative therapies continue to improve survival rates and quality of life.

In summary, early intervention, accurate diagnosis, and a tailored treatment approach are crucial for managing salivary gland tumours effectively. Benign tumours often have excellent outcomes, while malignant tumours require a combination of surgery, radiation, and sometimes chemotherapy to achieve the best results.

Key Takeaways: Understanding Parotid Tumours vs. Other Salivary Gland Tumours

Salivary gland tumours, though uncommon, vary significantly based on where they arise. Parotid tumours are the most frequent, with a majority being benign, while those in the submandibular, sublingual, and minor salivary glands carry a much higher risk of malignancy despite their rarity. Symptoms like lumps, facial weakness, pain, or difficulty swallowing can point to these tumours, and their presentation often depends on the gland involved.

The key takeaway is simple but vital: early detection saves lives. A small, painless swelling today could indicate something that requires prompt attention tomorrow. Ignoring these signs, however minor they may seem, can lead to unnecessary complications.

If you notice any unusual lumps, changes in facial sensation, or discomfort around the jaw, neck, or mouth, do not wait. Consult a healthcare professional who can guide you through the right diagnostic steps and treatment options.

When it comes to your health, being proactive is the greatest decision you can make. Early intervention often means better outcomes, quicker recovery, and peace of mind — because your health is too important to leave to chance.

References

1. Salivary gland tumors—Ear, nose, and throat disorders. (n.d.). MSD Manual Professional Edition. Retrieved December 18, 2024, from https://www.msdmanuals.com/professional/ear-nose-and-throat-disorders/tumors-of-the-head-and-neck/salivary-gland-tumors 
2. Parotid gland: Anatomy, function, location & definition. (n.d.). Cleveland Clinic. Retrieved December 18, 2024, from https://my.clevelandclinic.org/health/body/23232-parotid-gland 
3. Ghannam, M. G., & Singh, P. (2024). Anatomy, head and neck, salivary glands. In StatPearls. StatPearls Publishing. http://www.ncbi.nlm.nih.gov/books/NBK538325/ 
4. De Paula, F., Teshima, T. H. N., Hsieh, R., Souza, M. M., Nico, M. M. S., & Lourenco, S. V. (2017). Overview of human salivary glands: Highlights of morphology and developing processes. The Anatomical Record, 300(7), 1180–1188. https://doi.org/10.1002/ar.23569 
5. Bussu, F., Parrilla, C., Rizzo, D., Almadori, G., Paludetti, G., & Galli, J. (2011). Clinical approach and treatment of benign and malignant parotid masses, personal experience. Acta Otorhinolaryngologica Italica: Organo Ufficiale Della Societa Italiana Di Otorinolaringologia E Chirurgia Cervico-Facciale, 31(3), 135–143. 
6. Tille, J.-C., Reychler, H., Hamoir, M., Schmitz, S., & Weynand, B. (2011). Schwannoma-like pleomorphic adenoma of the parotid. Rare Tumors, 3(4), e40. https://doi.org/10.4081/rt.2011.e40 
7. A R, R., Rehani, S., Bishen, K. A., & Sagari, S. (2014). Warthin’s tumour: A case report and review on pathogenesis and its histological subtypes. Journal of Clinical and Diagnostic Research : JCDR, 8(9), ZD37–ZD40. https://doi.org/10.7860/JCDR/2014/8503.4908 
8.  Nascimento, L. A., Ferreira, J. A. S., Pio, R. B., Takano, G. H. S., & Miziara, H. L. (2014). Synchronous bilateral warthin tumors: A case report. International Archives of Otorhinolaryngology, 18(2), 217–220. https://doi.org/10.1055/s-0033-1351676 
9. Devaraju, R., Gantala, R., Aitha, H., & Gotoor, S. G. (2014). Mucoepidermoid carcinoma. BMJ Case Reports, 2014, bcr2013202776. https://doi.org/10.1136/bcr-2013-202776 
10. Quyen, H.-T. D., Duc, N. M., Tuan, H. X., Tu, N.-H. T., Khoi, N. A., & Dung, P. X. (2023). Acinic cell carcinoma of parotid gland. Radiology Case Reports, 18(6), 2194–2198. https://doi.org/10.1016/j.radcr.2023.03.017 
11. Rosero, D. S., Alvarez, R., Gambó, P., Alastuey, M., Valero, A., Torrecilla, N., Roche, A. B., & Simón, S. (2016). Acinic cell carcinoma of the parotid gland with four morphological features. Iranian Journal of Pathology, 11(2), 181–185. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939652/ 
12. Carlson, E. R., & Schlieve, T. (2019). Salivary gland malignancies. Oral and Maxillofacial Surgery Clinics of North America, 31(1), 125–144. https://doi.org/10.1016/j.coms.2018.08.007 
13.  Cantù, G. (2021). Adenoid cystic carcinoma. An indolent but aggressive tumour. Part B: Treatment and prognosis. Acta Otorhinolaryngologica Italica, 41(4), 296–307. https://doi.org/10.14639/0392-100X-N1729 
14. Zhang, M. H., Hasse, A., Carroll, T., Pearson, A. T., Cipriani, N. A., & Ginat, D. T. (2021). Differentiating low and high grade mucoepidermoid carcinoma of the salivary glands using CT radiomics. Gland Surgery, 10(5), 1646–1654. https://doi.org/10.21037/gs-20-830 
15.  Gontarz, M., Urbańska-Gąsiorowska, M., Bargiel, J., Gąsiorowski, K., Marecik, T., Szczurowski, P., Zapała, J., & Wyszyńska-Pawelec, G. (2021). Sublingual gland neoplasms: Clinicopathological study of 8 cases. Medicina Oral, Patología Oral y Cirugía Bucal, 26(5), e626–e631. https://doi.org/10.4317/medoral.24634 
16.  Adirajaiah, S., Anehosur, V., Sumana, & Gopalakrishnan, K. (2012). Adenocarcinoma of the sublingual salivary gland – A case report. Journal of Oral Biology and Craniofacial Research, 2(3), 206–209. https://doi.org/10.1016/j.jobcr.2012.10.004 
17. Vaidya, A. D., Pantvaidya, G. H., Metgudmath, R., Kane, S. V., & D’Cruz, A. K. (2012). Minor salivary gland tumors of the oral cavity: A case series with review of literature. Journal of Cancer Research and Therapeutics, 8 Suppl 1, S111-115. https://doi.org/10.4103/0973-1482.92224 
18. Noel, L., Medford, S., Islam, S., Muddeen, A., Greaves, W., & Juman, S. (2018). Epidemiology of salivary gland tumours in an Eastern Caribbean nation: A retrospective study. Annals of Medicine and Surgery, 36, 148–151. https://doi.org/10.1016/j.amsu.2018.10.039 
19. Pushpanjali, M., Sujata, D. N., Subramanyam, S. B., & Jyothsna, M. (2014). Adenoid cystic carcinoma: An unusual presentation. Journal of Oral and Maxillofacial Pathology : JOMFP, 18(2), 286–290. https://doi.org/10.4103/0973-029X.140796 
20.  Sankar Vinod, V., Mani, V., George, A., & Sivaprasad, K. K. (2013). Polymorphous low-grade adenocarcinoma––management and reconstruction with temporalis myofacial flap. Journal of Maxillofacial & Oral Surgery, 12(1), 105–108. https://doi.org/10.1007/s12663-011-0227-8 
21. Boahene, D. K. O., Olsen, K. D., Lewis, J. E., Pinheiro, A. D., Pankratz, V. S., & Bagniewski, S. M. (2004). Mucoepidermoid carcinoma of the parotid gland: The Mayo clinic experience. Archives of Otolaryngology--Head & Neck Surgery, 130(7), 849–856. https://doi.org/10.1001/archotol.130.7.849 

The thyroid is a butterfly shaped gland in the throat, responsible for a variety of endocrine-related processes in the body — from hormone production to regulating our metabolism. 

Goitre is a condition where the thyroid gland becomes abnormally large, causing discomfort and difficulty swallowing and breathing. It presents as visible swelling in the base of the neck, and can even cause thyroid dysfunction. How do we know if what we’re experiencing is just goitre, or something more serious, like thyroid cancer? 

In this article, Thyroid, Head & Neck Surgeon, Dr Tan Ngan Chye, walks us through everything we need to know to tell the difference between the two, and how to treat it. Read on to find out more! 

Goitre: Not just an iodine deficiency

Contrary to popular belief, goitre isn’t just caused by an iodine deficiency, and it can be caused by a variety of factors — from dietary deficiencies to autoimmune conditions. The most common causes of goitre include:

Iodine deficiency 

The most common cause for goitre is iodine deficiency. This is because iodine is essential for thyroid hormone production, and the thyroid gland enlarges in an attempt to capture more iodine. Iodine supplements or consuming iodine-rich foods, such as iodised salt, seafood and seaweed could help increase your dietary iodine intake. 

Autoimmune disorders

Certain autoimmune disorders, where the body mistakenly attacks healthy cells, can lead to various thyroid disorders, such as:

• Graves’ disease – Graves’ disease is an autoimmune disorder where the body attacks the thyroid, leading to hyperthyroidism and goitre development [1, 4].
  
  
• Hashimoto’s disease – Hashimoto’s thyroiditis is also an autoimmune disorder where the body produces antibodies that attack the thyroid cells. 

Medications or environmental factors

Some types of medications (e.g. lithium), or exposure to environmental toxins can, in some cases, cause thyroid enlargement. 

Hormonal changes

Temporary hormonal shifts, such as during pregnancy or puberty, can increase thyroid activity and lead to a goitre. 

Infection or inflammation

Thyroiditis, or inflammation or infection of the thyroid, can cause swelling of the thyroid gland. 

Genetic predisposition

A family history of thyroid issues or other genetic conditions can increase an individual’s risk of developing goitre as well.

Thyroid cancer

Thyroid cancer can cause goitre when malignant cells proliferate, causing abnormal growth of thyroid tissue. 

It can be confusing to identify the different types of goitres, hence it is always recommended to seek medical attention for a proper diagnosis.

Thyroid Cancer vs. Goitre

Thyroid cancer is caused by the abnormal growth of malignant cancer cells in the thyroid gland. There are 4 main types of thyroid cancer:

• Papillary thyroid cancer (PTC) – The most common type of thyroid cancer, which is derived from the follicular cells of the thyroid. These cancers are also likely to spread via lymph nodes [6].
  
  
• Follicular thyroid cancer (FTC) – Thyroid cancer derived from follicular cells which are more aggressive than PTC, and are more likely to spread via the bloodstream [6].
  
  
• Medullary thyroid cancer (MTC) – Cancers derived from neuroendocrine cells or parafollicular cells [7, 8]. MTCs can be genetically inherited in multiple endocrine neoplasia (MEN) type 2 syndrome [8].
  
  
• Anaplastic thyroid cancer (ATC) – This is a rare and aggressive type of thyroid cancer. ATCs are thought to be linked to genetic mutations such as BRAF, RAS, and TP53 genes [9].

Unfortunately, the appearances of thyroid cancers and goitres are similar, and it can be a challenge to differentiate the rare cases of thyroid cancers from the more common incidences of goitres. Most clinicians diagnose thyroid cancers from nodules found on the thyroid, whereby about 5% of thyroid nodules found are malignant [5, 10].

Oftentimes, goitres and thyroid cancers can appear similar, especially with nodular goitres. Here are some key differences:

Feature	Goitre	Thyroid Cancer
Cause	Can be caused by multiple factors, such as insufficient dietary iodine, autoimmune disorders, or underactive thyroid activity. Goitres can also have no known cause.	Caused by the presence of malignant (cancerous) thyroid cells caused by genetic mutation or radiation.
Growth	General enlargement of thyroid, can be smooth or nodular/multinodular.	Often presents as a single, firm, and rapidly growing lump.
Key symptoms	General enlargement of thyroid glandChanges in metabolism or energy levelsMay lead to hypothyroidismFatigueSensitivity to coldDry skin ConstipationMuscle weaknessMay lead to hyperthyroidismWeight lossRapid heart rateSensitivity to heatExcessive sweatingTremorsIncreased appetiteMuscle weaknessFrequent bowel movementsDysregulated menstrual cycleHigh blood pressure	Thyroid nodule or lump on your neckSwollen lymph nodes in your neckNausea and vomitingUnexpected weight loss
Progression	Goitres develop slowly over time.	Thyroid cancer may have a more rapid progression, over weeks or months.

In general, goitres may present more diverse symptoms that accompany thyroid enlargement, this includes metabolic and hormonal symptoms. While a lump on the neck with swollen lymph nodes may indicate metastasis of the thyroid cancer. It is always recommended to consult a doctor to get a proper and complete diagnosis. 

How can my doctor tell the difference?

Your doctor will perform several tests to identify a malignant growth from a benign thyroid enlargement [1]:

• Thyroid function test – This test checks for thyroid stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4) levels in the patient. This may identify whether goitres are euthyroid or toxic. Calcitonin level can also be evaluated if MTC is suspected.
  
  
• Ultrasonography – Ultrasonography is an imaging test that allows doctors to differentiate between possibly malignant growths and non-malignant ones. The doctor will usually look for features such as irregular borders of the growth, vascularisation, hypoechogenicity (refers to how well the tissues send back ultrasound waves, this can be an indication of tissue density and composition), lymph node metastasis, and microcalcifications.
  
  
• Fine needle aspiration cytology (FNAC) – This test involves taking tissue samples from the thyroid with the help of ultrasound. The tissue sample is then sent for laboratory tests to identify the presence of cancerous markers or features.

Risk factors of thyroid cancer

In general, thyroid cancers and goitres share certain similar risk factors such as:

• Gender – Similar to goitres, thyroid cancer is more common in women than in men.
  
  
• Age – Thyroid cancer risk increases with age.
  
  
• Family history and genetics – Familial history of thyroid issues or thyroid cancers, as well as genetic conditions like multiple endocrine neoplasia type 2 can increase the risk of thyroid cancer.
  
  
• Radiation exposure – Radiation exposure to the head and neck region, such as from radiotherapy for head and neck cancers, or from occupational exposure.
  
  
• Iodine imbalance – Low iodine diet can increase the risk of thyroid cancer.
  
  
• Excess body weight and obesity – Studies have shown a clear relationship between having excess body weight and thyroid cancer [11].
  

However, thyroid cancers may have specific causes such as MEN type 2 syndrome and genetic mutations such as BRAF and RAS genes.

When do I need to see a doctor?

Pay attention to your body. If you experience any of the symptoms that concern you, let your doctor know so that they may address them and advise you. Visit a doctor if you experience the following:

• You have a lump or swelling on your throat that persists or changes in size – This can be due to nodular goitres, which have the potential to be diagnosed as thyroid cancer.
  
  
• Signs of thyroid dysfunction – Symptoms of thyroid dysfunction include:
  • abnormal changes in metabolism and energy levels
  • sensitivity to temperature extremes
  • sudden weight loss
  • increased sweating
  • tremors
  • mood changes, irritability or depression
  • hoarseness or changes in your voice
  • Resistance when swallowing 
    
    
• Swelling of the neck lymph nodes – Lymph node swelling around the neck can be caused by bacterial or viral infections, thyroid issues, or cancer. 
  
  
• Hypothyroidism – Hypothyroidism refers to the thyroid not making enough thyroid hormones, this can affect your metabolism, energy levels, and mood, among other issues.
  
  
• Hyperthyroidism – Hyperthyroidism is the opposite of hypothyroidism, where the thyroid is overactive in producing hormones. This is typically observed in toxic types of goitres.
  
  
• Breathing and swallowing difficulties – Obstruction of the throat by the enlarged goitres can affect breathing and swallowing.
  

Summary

It can be challenging for individuals to distinguish the difference between a goitre and thyroid cancer, and knowing their key differences is important — but sometimes, professional medical advice is necessary. Your doctor can use diagnostic tools to accurately determine whether the swelling in your throat is due to benign goitre or thyroid cancer, because we can’t rely on visual or symptomatic queues alone.

If you’re experiencing any of the above, consult your doctor. Early evaluation and timely treatment can make all the difference in achieving optimal medical outcomes. Schedule a consultation with us today for a comprehensive diagnosis and personalised treatment plan. 

References

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