Just a Mole or Skin Cancer? Here’s How to Tell

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

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

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