Amelanotic melanoma: Don’t let these ‘skin coloured’ spots go unnoticed

Amelanotic melanoma is relatively rare, accounting for 1–8% of all melanoma skin cancers. Like other types of melanoma, it occurs when the melanocyte cells undergo abnormal change. This causes quick and uncontrollable cell growth and division.

The main issue with amelanotic melanomas is that because they lack pigment, they are not as obvious. Or they may be mistaken for harmless scars or benign lesions. This can delay diagnosis and result in a poorer prognosis.

While amelanotic melanomas lack pigment, there are other characteristics to watch out for. If you notice any of the following factors, we recommend a professional skin check.

• A mole or lesion that has changed in size or appearance
• Changes in texture (including skin thickness)
• Skin that becomes painful, bleeds or crusts
• Skin feels fragile or tender 
• An open sore that takes more than three weeks to heal or heals and then returns

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A simple and useful method for spotting melanoma symptoms is the ‘ugly duckling’ rule. This refers to any mole or spot that stands out or looks dif­fer­ent from other moles on the body. This can be helpful because benign moles tend to look alike.

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Dermoscopy (using a dermatoscope to examine the lesion) can be helpful for diagnosing amelanotic melanoma. Yet, because the lesions lack pigment, amelanotic melanoma can be challenging to diagnose. 

If, after careful examination, amelanotic melanoma is suspected a biopsy will be performed. This involves the surgical removal of the lesion along with a margin of healthy tissue. This is sent to a pathologist for evaluation under a microscope and diagnosis. Any type of melanoma can be amelanotic, but the four most common types of melanomas are:

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• Superficial spreading melanoma
• Nodular melanoma
• Lentigo maligna melanoma
• ‍Acral lentiginous melanoma

The stage of the skin cancer indicates whether the cancerous cells have spread and determines the treatment. Amelanotic melanoma is staged in the following way:

Stage 0

The melanoma remains in the outer layer of skin (epidermis). This is also known as melanoma in situ.

Stage 1

The amelanotic melanoma is less than 1 mm thick and has grown beyond the surface layer of skin. There is no evidence of spreading (metastasis).

Stage 2

This refers to melanomas that are greater than 1 mm thick and in the early stages. They have not spread but are at high risk of metastasis.

Stage 3

This is an advanced melanoma that has spread to the lymph nodes or nearby tissue.

Stage 4

This type of amelanotic melanoma skin cancer has spread to distant areas of the body, such as the lungs or brain.

The most common treatment for amelanotic melanoma is surgery. The cancerous tumour as well as a small amount of healthy surrounding tissue, called a margin, is removed. If cancer has been detected in the lymph nodes, a lymph node dissection may also be needed. 

Other treatment, that may be used alone or in combination with surgery include:

• Radiation—high-energy x-rays are applied to the tumour. This destroys the cancerous cells by damaging their DNA.
• Immunotherapy—medicines (immune checkpoint inhibitors) are used to assist the body’s immune system to find and kill the cancerous cells.
• Targeted therapy—medication blocks the growth of cancer by intercepting certain gene mutations in the cancerous cells.

The overall five-year survival rate for melanoma is around 93%. According to one study, the survival rate for amelanotic melanoma is slightly lower at 88%. This is largely due to delayed diagnosis leading to detection in the advanced stages.

Given that 95% of melanomas are a result of overexposure to the sun, following the sun safety rules can help keep your skin safe. This includes:

• Wearing broad-spectrum sunscreen (ideally SPF 50+)
• Minimising UV exposure when the UV index is 3 or higher (typically between 10am and 3pm)
• Seeking shade when outdoors and wearing sun protective clothing and accessories (such as a wide-brimmed hat and sunglasses) 

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Since amelanotic melanomas are often ‘skin coloured’ they can be harder to notice. All too often they are mistaken for other skin conditions, delaying diagnosis. Paying regular attention to your skin and being aware of any changes can support early detection and timely treatment.

At MoleMap, we recommend regularly (at least every three months) checking your skin for new moles and changes in existing moles. Any unusual skin changes should be promptly checked out by a professional. This is essential because early-stage melanomas are highly treatable and often curable.

For anyone at high risk of melanoma, we recommend a Full Body MoleMap. This is our most comprehensive skin check. It includes a thorough skin assessment with dermatologist diagnosis, total body photography, additional dermoscopic imaging of moles that may be at risk, and unlimited free spot checks for 12 months.

A Skin Check is ideal if you’ve spotted a new or suspicious mole or lesion and want it checked out quickly. A melanographer (a nurse trained in skin cancer detection and triage) will examine your skin. Dermoscopic (under the skin) images are taken of any suspicious spots. Within 10 working days, you’ll receive a full dermatologist diagnosis with advice on the next steps, if needed.

Got an ‘ugly duckling’ mole or want peace of mind that your skin is healthy?  Compare our services and find your nearest MoleMap location.