Skin cancer is relatively rare in Singapore with an incidence rate of 0.3 to 0.5 per 100,000 people annually. However, frequent headlines [1] continue to highlight the disbelief of many Singaporeans who are caught off-guard by a skin cancer diagnosis. The prevalence of the myth that Asians are safe from skin cancer has created a complacent society, especially in Singapore where levels of ultraviolet radiation are strikingly high throughout the year [2]. In fact, the UV index hit “extreme” levels in March 2024, and this is likely to happen again on the backdrop of global climate change [3]. It is important to note that;
In this article, we aim to provide a comprehensive guide on all matters related to moles, skin cancers, screenings, treatment options, and prevention strategies. By raising awareness about the prevalence of skin cancer in Singapore, we hope to cultivate the habit of undergoing routine checks and screening among Singaporeans and expatriate communities.
The sun is a great source of vitamin D [7], a vital nutrient that helps maintain and strengthen your bones, on top of optimising your brain health [8]. Although it is ill-advised to stay indoors for an extended period, too much sun exposure can damage your skin by inducing photocarcinogenesis, a process that encourages the development of skin cancers.
The driving factor of skin cancer is overexposure to sunlight, particularly if one is prone to sunburns. UV rays from the sun induce damage to the skin’s DNA, catalysing the formation of abnormal cells that divide and mutate rapidly. In fact, intermittent severe sun exposure caused by acute sunburns is a major risk factor for the development of skin cancers [9].
The type of skin cancer is typically classified by where the cancer begins.
There are three primary types of skin cancer, which are:
Identifying the stage of skin cancer is crucial in determining the appropriate treatment and prognosis. The stages of skin cancer are broken into the following stages:
| Stages | Description |
| Stage 0: Carcinoma In Situ | The cancer cells are located in the epidermis (outermost layer) of the skin and have not penetrated deeper |
| Stage 1: Localised | The cancer cells are small and confined to the initial area. It has extended beyond the epidermis but often remains localised to the upper layer of the dermis. |
| Stage 2: Localised with higher risk | The cancer is larger and accompanied by certain high-risk features. However, it has yet to spread to the lymph nodes or grow beyond the initial area |
| Stage 3: Regional spread | The cancer has spread to nearby lymph nodes, and tissues, but not to different parts of the body |
| Stage 4: Metastatic | The cancer has metastasised to other organs and lymph nodes of the body |
Although skin cancer is arguably rare in Singapore, several risk factors increase your likelihood of developing it, especially when it is combined with excessive sun exposure. These risk factors include:
| Lifestyle Habits | History | Skin Condition |
| Frequent sun exposureFrequent use of tanning bedsSpending time outdoors without sun protective measures | A family history [10] of skin cancerA history of blistering sunburns in childhood [11]History of previous skin cancer or precancerous skin changesFamily history of skin cancersA history of previously having received chemotherapy or radiation | Presence of multiple Actinic keratoses [12]Moles, especially irregularly shaped and coloured molesExtensive frecklingHave more than 50 moles throughout the bodyLight skin types Prone to sunburn |
Another risk factor that contributes to the risk of developing skin cancer is skin type. In fact, fair-skinned individuals are more at risk of developing skin cancer – specifically melanoma – than people with naturally dark skin tones. This is because fair-skinned individuals have less melanin [13] in their skin, compared to individuals with darker skin tones. Due to the limited melanin, individuals residing in tropical-climate countries are more at risk [14] of developing skin cancer in their lifetime.
To understand the risk factors associated with skin tones, we need to understand the Fitzpatrick skin types, which essentially classify the skin’s reaction to sunlight among individuals.
| Skin Type 1 |
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| Skin Type 2 |
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| Skin Type 3 |
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| Skin Type 4 |
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| Skin Type 5 |
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| Skin Type 6 |
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However, being Asian or having a darker skin tone should not make you complacent about sun protection, as skin cancer does not discriminate based on skin tone. A 2009 study [15] revealed that fairer-skinned Singaporean Chinese were three times more likely to develop skin cancer compared to their Malay and Indian compatriots. Despite being a skin phototype 4 to 6, it is important to remember that skin tone is not the sole driving force behind this highly preventable disease. Beyond skin tone, factors such as hormones, genetics, lifestyle habits, age and environmental exposures all contribute to the development of skin cancer.
Skin moles are formed because of abnormal skin cell growth and are often developed between early childhood and 20 years old. It is common for an adult to have between 10 and 40 moles throughout their body.
Overexposure to sunlight can stimulate the development of new moles in adulthood, thereby increasing the risk of melanoma. Moles progress into melanoma [16] when melanocytes divide uncontrollably due to excessive sunlight exposure, causing genetic changes inside the mole cells. While there is no definitive rate for how quickly or slowly melanoma progresses, it is believed that melanoma can develop within a few months.
There are several types of moles, including:
Because moles are common, it is easy to mistake moles for other skin conditions such as freckles, melasma and pigmentation. But each skin condition is unique with distinctive features, as per the table below:
| Feature | Moles | Freckles | Solar Lentigenes or Sun spots | Melasma |
| Appearance | Raised or flat and may be round or oval | Discrete, Flat, small, tan to brown spots | Discrete, flat brown spots | Vague brown patches resulting in an uneven skin tone |
| Colour | Black, brown, tan, pink, or skin-coloured | Light brown to dark brown | Light brown to dark brown | Brown to grey-brown |
| Size | Varies but can be larger than freckles | Small, typically 1-2 mm | Varies but usually larger than freckles | Often larger patches |
| Location | Anywhere on the body | Sun-exposed areas (face, arms) | Sun-exposed areas (face, arms) | Face (forehead, cheeks, upper lip) |
| Cause | Clusters of pigmented cells | Genetics, Intermittent sun exposure | Genetics, cumulative lifetime sun exposure | Hormonal changes, sun exposure, photoaging, genetics |
| Gradual Changes | Can change in size, shape, or colour | May fade with sun avoidance and appear with sun exposure | May darken with sun exposure but does not lighten much with sun avoidance | Becomes more pronounced with sun exposure |
| Risk of Skin Cancer | Some moles can become cancerous | Not cancerous | Not cancerous | Not cancerous |
| Treatment Option | Monitoring, and removal of suspicious or evolving moles | Sun avoidance, topical lightening agents, lasers | Sun avoidance, Topical lightening agents, lasers | Sun avoidance, topical lightening agents, chemical peels, lasers, oral medications |
Understanding and being aware of these differences will aid you in distinguishing between moles from other skin conditions. This will inherently help you in being more aware of any changes to your skin, with regards to mole development.
The key step to preventing skin cancer is to monitor the possible changes in your moles, especially if you have a higher risk of developing the disease. One of the methods for monitoring these changes is by routinely practising a skin self-examination by relying on the ABCDE guide. It entails:
If you managed to identify at least two changes, then it is time to have it properly and thoroughly examined by a dermatologist.
As melanoma has distinctive features, skin-self examination can be performed by individuals and their loved ones at one to three-monthly intervals. Many new and recurrent melanomas could potentially be detected, especially if there is access to previous photographs taken of the moles that are being monitored [17]. A thorough skin-self examination involves looking at often overlooked sites such as the fingerwebs, toewebs, scalp, retroauricular skin, natal cleft, back and back of the legs. Do bear in mind that the back is the most commonly affected area in men, and the back of the legs is the most commonly affected area in women.
When it comes to skin cancer, early detection and treatment are crucial in treating the disease. That is why individuals who pose an increased risk of developing skin cancer, especially expatriates residing in tropical-climate countries, are advised to undergo routine skin cancer screening.
As daunting as it sounds, skin cancer screening is a non-invasive and quick procedure. A full-body skin examination typically lasts between 15 to 20 minutes. Make a mental note of the moles that you are concerned about prior to your appointment, so we can discuss them with you in detail. In addition, it would be useful for you to bring any previous clinical photographs of your skin (if applicable) so we can assess your skin changes longitudinally over a period of time.
Before the appointment, it is recommended that you do the following steps to save time and improve efficiency during the procedure:
Skin cancer screening involves examining your skin for possible signs of precancerous conditions or skin cancer. Here is a step-by-step guide to what the procedure entails:
| Step 1:Private and Comfortable Environment | As your comfort is our priority, Dr. Evelyn Tay, who is a fellowship-trained dermatological surgeon, will conduct skin checks in a private and comfortable setting. |
| Step 2:Meeting with Dr. Evelyn | Dr. Evelyn will manage your care with extensive experience in detecting and managing skin cancers. At this stage, Dr. Evelyn will assess your medical history and ask about your lifestyle habits along with your sun protection measures to understand your risks of developing skin cancer. |
| Step 3: Skin Cancer Screening Procedure | Afterwards, Dr. Evelyn will perform a detailed skin screening by using a dermatoscopy and polarised light to identify any suspicious lesions. Skin checks will involve a thorough examination of the skin from the top of your scalp to the bottom of your feet. |
| Step 4: Photographic Documentation of Skin Moles and Lesions | After the procedure, our staff will take photographs of your skin lesions.. This will allow us to monitor and track their progress over time, thereby ensuring early detection and effective monitoring, while reducing the need for unnecessary biopsies. We will also be sending you a copy of those photographs, which will come in handy for your skin self-examination. |
Studies have shown that skin cancer screening performed by trained specialists has a higher rate of detection of skin cancers [18]. Beyond early detection, mole checks and skin cancer screening offer a list of benefits, including;
Identifying the stage of skin cancer is crucial in determining the appropriate treatment and prognosis. The table below details the types of treatments available depending on your diagnosis;
| Stages | Treatment |
| Stage 0: Carcinoma In Situ | Topical treatment, surgical excision, curettage and cautery, cryotherapy, photodynamic therapy |
| Stage 1: Localised | Excision, curettage and cautery (in suitable cases), topical treatment (in suitable cases), photodynamic therapy (in suitable cases) |
| Stage 2: Localised with higher risk | Surgical excision with close surveillance |
| Stage 3: Regional spread | Surgical excision with close surveillance may require radiation therapy, targeted therapy or chemotherapy |
| Stage 4: Metastatic | Treatment often involves a combination of surgery, radiation therapy, chemotherapy, immunotherapy or targeted therapy. However, this will depend on the location and extent of the cancer spreading |
Although there is an array of treatment options available for treating skin cancer, it is important to understand that each treatment plan is unique to every patient. While a singular treatment may suffice for some, others may require a combination of treatments. This will be determined by how progressive the cancer is. Below are some of the treatment options that are available at Lumine Dermatology;
MOHS micrographic surgery is a highly precise and specialised dermatological surgery that is mainly used to treat skin cancers, including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). It involves systematically removing thin layers of cancerous tissue and immediately examining them under a microscope, continuing this process until no cancer cells are detected. Additionally, MOHS surgery is designed to conserve as much healthy tissue as possible. This not only helps to minimise scarring but, will achieve better cosmetic results too. MOHS surgery also offers excellent cure rates for non-melanoma skin cancer, specifically up to 99% for new cases and 94% for recurrent cases [20]. Similarly, it is particularly suitable for treating skin cancers in cosmetically sensitive areas, recurrent skin cancer cases and aggressive tumours with unclear boundaries.
| STEPS | DESCRIPTION |
| Preparation | The area around the skin cancer is cleaned and a local anaesthetic is applied to numb the area. |
| Tissue Removal | The surgeon removes the visible tumour along with a thin layer of surrounding tissue. This tissue is also marked and mapped to indicate its orientation. |
| Mapping and Sectioning | The removed tissue is divided into sections and colour-coded to correspond to the specific areas of the surgical site. A detailed map of the tissue is created to guide further removal if needed. |
| Microscopic Examination | The tissue sections are frozen, cut into very thin slices and examined under a microscope. Afterwards, the surgeon looks for cancer cells at the margins of each section. |
| Additional Tissue Removal | If cancer cells are found at the margins, the surgeon removes another thin layer of tissue from the precise area where the cancer cells were detected. This step is repeated until cancer cells are no longer present. |
| Wound Reconstruction | Once all cancer cells have been removed, the surgeon closes the wound usually within the same day. Some of the options include allowing the wound to heal naturally, stitching it closed, or using a skin graft or flap. |
| Follow-up | The patient is scheduled for follow-up appointments to monitor the healing process and check for any signs of recurrence. The surgeon may also provide care instructions and information on how to protect the skin. |
A wide local excision indicates the removal of the entire cancerous area, including a 4–10-millimetre margin of the surrounding tissue. It is often used to treat BCC, SCC and early-stage melanomas. Wide local excision boasts at least a 90 to 94% cure rate for low-risk skin cancers, [21] aside from being one of the most cost-effective forms of treatment. Additionally, the treatment options are also beneficial for specific skin cancers that exhibit unpredictable growth patterns, like melanoma and extramammary Paget's disease.
| STEPS | DESCRIPTION |
| Marking the Area | The surgeon will begin by marking the boundary around the skin lesion. This will also include the surrounding tissue, measuring roughly between a margin of 4 – 10 millimetres, depending on the diagnosis. |
| Administering the Anesthesia | Afterwards, local anaesthesia will be administered to numb the surgical area. However, if the surgical area is extensive, then the surgeon may opt for sedation or general anaesthesia to minimise discomfort throughout the procedure. |
| Incision and Excision | The surgeon proceeds to make an incision around the marked area to remove the lesion and its surrounding tissue. Additionally, the surgeon may mark the excised tissue for orientation to help pathologists assess the margins. |
| Bleeding Control | Before closing the wound, the surgeon will inspect the surgical area for any bleeding. If bleeding is found, the surgeon may opt to control the bleeding by cauterization or suturing. |
| Wound Closure | The wound is closed either with sutures, skin grafts, or flaps. This will depend on the size of the treated area. |
| Dressing and Postoperative Care | A sterile dressing is applied to prevent the wound from getting infected. This will also entail post-operative care instructions, including follow-up appointments. |
| Pathological Examination | The excised tissue is sent to a pathology lab to confirm the complete removal of cancer cells and confirm clear margins. |
| Follow-up | As soon as the pathology results come back, the patient is briefed of the results and the surgeon will advise on the next course of action. This will possibly include timely monitoring or additional therapies, depending on the results. |
Although curettage and cautery (C&C) are less precise compared to MOHS surgery and wide local excision, C&C is often used to treat premalignant skin cancer and superficial basal cell carcinomas. Similarly, it offers a 98% cure rate [22] for suitable skin lesions.
| STEPS | DESCRIPTION |
| Pre-procedure Preparation | Prior to the procedure, the surgeon will inform the patient of the procedure, including the risks, benefits and aftercare. Once the patient has been briefed, local anaesthesia will be administered to minimise discomfort. |
| Curettage Procedure | The lesion is scrapped off using a spoon-shaped instrument called a curette. During this step, the abnormal cells in the epidermis and superficial dermis are removed. |
| Cautery Procedure | The area is then cauterised using an electrocautery device to help remove any remaining cancerous cells and halt any bleeding. |
| Wound Dressing | Once the procedure is complete, the surgeon will proceed to cover the area with a sterile dressing. |
| Follow-Up | The surgeon will schedule a follow-up appointment to monitor how the wound is healing and determine if additional treatment is necessary. |
Beyond MOHS surgery, wide local excision and C&C, some of the additional treatment options include:
Whether you are a local or an expatriate residing in Singapore, it is imperative to improve your sun protective measures as doing so will lower the likelihood of you developing skin cancer. We have come a long way from applying olive oil on the skin of our children when they go to the beach, and blistering sunburns are becoming a thing of the past. Here are some of the steps that you can take to protect your skin from the harmful damage of UV rays. Remember the 5s: Slip, Slop, Slap, Seek and Slide.
| Slip: Choosing the right clothing | The clothes you choose to put on are one of the easiest and most effective ways to protect your skin from harmful UV rays. Look for UV protection clothing, which usually comes with a UV protection factor (UPF) rating. A UPF of 25 means that only 1/25 th of UV (~4%) is allowed to penetrate clothing, while a UPF of 50 means that 1/50 th of UV (~2%) is allowed to go through. A white cotton T-shirt that does not come with a UPF rating typically has a UPF of 5, which means that 1/5 th of UV (~20%) is allowed to pass through. This UPF drops even further if the white T-shirt is wet. Hence, it is important to select appropriate clothing as some clothing may give a false sense of protection when out in the sun. Opt to discard or recycle old and worn fabrics, as the UPF drops with repeated washes. Dark-coloured clothing (e.g black, navy) are generally better at absorbing UV rays than light-coloured clothing, conferring a higher degree of protection. |
| Slop: Applying sunscreen | Sunscreen acts as the first line of defence against harmful UV rays. Whether you will be out the whole day or running a quick errand, it is advisable to apply sunscreen. When it comes to sunscreen, do remember the following tips:
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| Slap: Wearing the right hats | On top of applying sunscreen, it is encouraged for you to put on hats. It is effective at protecting your face, head, neck and ears from harmful UV rays. So, when choosing your hat, pay attention to the following criteria:
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| Seek: Go to where the shade is | The strength of the sun’s UV radiation is measured in the form of UV index (UVI). In sunny Singapore, the average maximum UVI ranges from 8 to 10, which is very high. In fair-skinned individuals and those prone to developing skin cancers, it helps to check the UVI before heading out and to dress appropriately, walk in the shade or bring an umbrella. It is helpful to even avoid being outdoors when the UVI is very high. UVI can be checked on the NEA website (https://www.nea.gov.sg/weather/ultraviolet-index) or by downloading various apps on one’s handphone.Reflection off snow and water can also significantly increase UV exposure and this should be taken into account when planning the relevant activities. |
| Slide: Protect your eyes too | UV radiation not only puts you at risk of developing skin cancer around the eyes, but it also brings about a host of eye-related concerns, such as cataracts [23]. The next time you step outside, do not forget your sunglasses. If you are planning on purchasing new sunglasses, consider these criteria:
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Secondary prevention of skin cancers
In high-risk individuals, we routinely prescribe nicotinamide [24] and Polypodium leucotomos extract [25]. Nicotinamide, which is an active form of vitamin B3, boosts cellular energy and enhances DNA repair on a molecular level and has been shown in clinical trials to reduce the amount of actinic keratosis and NMSCs in susceptible individuals. Polypodium leucotomos has been found to neutralize free radicals and reduce mutations associated with UV exposure, also known as UV signature mutations. It has been purported to not just reduce photodamage, but also delay photoaging. These oral agents hold much promise and more research needs to be done in how they can be used to complement, but not replace, traditional photoprotection strategies such as behaviour modifications, clothing and sunscreen use.
Ensuring your skin’s health is paramount, especially when residing in a sunny country like Singapore. As skin cancer often develops silently, it is imperative for you to schedule regular screenings as early detection of skin cancer is crucial for improving the treatment success and survival rates. It is equally important to choose a highly skilled and experienced dermatologist who is proficient in identifying subtle changes in your skin as it can make significant differences in the management and treatment outcomes. Prioritising these steps, not only helps in early intervention but contributes to better overall health.
At Lumine Dermatology and Laser Clinic, Dr. Evelyn Tay offers expert mole checks and skin cancer screenings for early detection to provide her patients with peace of mind. Armed with her wealth of knowledge and extensive years of experience offering dermatological services and sound assessment, Dr. Evelyn understands the unique dermatological needs of her patients, making her the ideal and go-to choice for your skin health. Schedule an appointment today at Lumine Dermatology and Laser Clinic to take a proactive step towards healthier skin.
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