Dermoscopy of Amelanotic Melanoma

Melanoma is the most invasive and dangerous of the common forms of skin cancer with the highest risk of death. Melanoma moves very quickly, it can spread to other parts of the body. If untreated, melanoma can became life-threatening even in 6 weeks. Amelanotic melanoma is the highly aggressive form of melanoma that does not produce pigment from common melanomas. Hence amelanotic melanoma is usually more easily neglected by people. Early detection by dermoscopy is very important. If caught and treatment in early stages, it will bring a nearly 99% five-year survival rate.

What is Amelanotic Melanoma?
Amelanotic melanoma is a invasive type of skin cancer in which the maligant cells have almost no pigment. While the truly amalenotic melanomas that lesions lack of all pigment is rare, it does not means without any pigment, it means lacking of pigment or its pale pigment. As a result, it looks different from other melanoma. Instead, amelanotic melanoma may appear pink or even reddish, with gray or brownish edges on skin.

Amelanotic melanomas are uncommon, accounting for about 2% to 20% of all melanomas. Although they are rare, they are just as dangerous as the more common pigmented melanoma. Their lack of pigmentation makes them harder to detect and diagnose.Often overlooked or confused with other benign skin lesions, amelanotic melanomas may be diagnosed at a later stage than brown, black, or blue common melanomas. This bring more dangerous than other common melanomas.

What Causes Amelanotic Melanoma?
Amelanotic malenoma is caused by genetic changes to the cells in moles. It is also called genetic mutations of amelanotic melanoma. Genetic mutation causes uncontrolled growth of melanocytes that produce pigment in the skin. The factors of these genetic changes is not exactly clarify, but several high risk factors have been identified that may increase the possibility of developing amelanotic melanoma, suck as: exposure to ultraviolet (UV) radiation, a history of family, weakened immune system, age growing and so on.

High Risk Groups of Amelanotic Melanoma
There are some high risk groups that may be more likely to develop amelanotic melanoma like below:
People with a lots of moles or atypical mole
People with fair skin
Over exposure to UV radiation
A family history of melanoma
People with weakened immune systems
Older adults, specially over 50 years

What are Clinical Features of Amelanotic Melanoma?
Amelanotic melanoma is a type of skin cancer which lacks of pigment. Hence amelanotic melanoma is more challenging to detect compared to pigmented melanomas. The clinical features of amelanotic melanoma can be varied, but some typical features includes:
A little of pigmentation or without any pigmentation
Pink, reddish or flesh-colored lesions on the skin.
The shape of a amelanotic melanoma is usually asymmetrical
Bounders of amelanotic melanoma may be uneven, jagged, or blurred.
Amelanotic melanoma may change in its size, shape, or color over time.
Some amelanotic melanomas may bleed, scab, or form an ulcerated area in the center.
Amelanotic melanomas can grow quickly and may exhibit rapid changes in appearance
Amelanotic melanoma may quickly worsen its physical sign especially in late stage.

Because lacking of pigmentation, so amelanotic melanoma can be easily mistaken for other benign or malignant skin diseases, such as basal cell carcinoma, squamous cell carcinoma, dermatofibroma, hemangioma, dermatosis papulosa nigra, seborrnheic keratosis, ect. So it is crucial to identify amelanotic melanoma by dermatoscope particularly in its early stage.

Dermoscopy of amelanotic melanoma
What is dermoscopy?
A dermoscopy is a hand-held visual aid device used by a person or dermatologist to examine and detect skin lesions and diseases, such as melanoma. It is also called dermoscopy, epiluminescence microscopy and skin surface microscopy. A dermoscopy utilizes a powrful optical system and big magnification to greatly enhance the visual of skin even some hard-to-reach areas by naked eyes. Dermoscopy helpes doctors to explore more details of the skin. The whole process under dermoscopy is non-invasive and painless.

What are the dermoscopic features of amelanotic melanoma?
Dermatoscope plays a crucial role in the detection and diagnosis of skin cancer, like amelanotic melanoma, which making a more difficult identifying due to its lacking the dark pigmentation compared to common melanoma. While dermoscopy allows skin doctors to inspect subtle details and structures invisible by naked eyes. Dermatoscopy is particularly a dependable and valuable tool for diagnosis of amelanotic melanoma. There are some certain features under dermoscopy as below: Pigmentation residue:Irregular pigmentation/pigmentation residue (if present) Structureless areas：White structureless areas, blurred and fuzzy areas. Irregular vascular patterns:Irregular dotted vessels, linear irregular vessels, comma-shaped vessels, beside helical vessels are strongly specific form of amelanotic melanoma.
Ulceration or bleeding: Detecting ulceration or bleeding with the lesion, indicating a more advanced stage of the amelanotic melanoma. Asymmetry and irregular borders: Clearly highlight asymmetry and irregular borders in amelanotic melanoma, distinguish it from benign lesions. Atypical pigment netwok: Atypical, non-uniform pigmented lines or dots in some cases exhibit by dermoscopy, like white lines.
Abnormal structures: Such as disordered structures, blue nipples and blue-white papules abnormal structures.

The difference between malignant melanoma and amelanotic melanoma
Amelanotic melanoma and malignant melanoma are two types of melanoma. Both of them are aggressive and dangerous. The main differences of amelanotic melanoma and malignant melanoma lie in their appearance and absence of pigment. Amelanotic melanoma usually appear as non-pigmented lesions with atypical colors due to lacking melanin, while malignant melanoma appear as black or dark pigmented lesions with melanin.

How to detect lesions of amelanotic melanoma?
It is very crucial to use dermoscopy for regular examination of suspicious skin lesions. Pay attention to any changes in structures, shapes and colors, such lesion morphology. If any atypical features found, it is better to look for help from skin doctors.

Amelanotic melanoma is a type of hidden skin lesion which lacks of melanin, resulting in a difficult diagnosis. While dermoscopy is an reliable and useful device to observe and detect melanoma, especially the amelanotic melanoma type, which may not display the common and typical features related with melanoma. By greatly enhancing the visualization of subtle structures and patterns of skin, dermoscopy supports early identification and accurate diagnosis of this challenging variant of skin cancer, thereby improving confidence of patients and dermatologists.

It is necessary to operate dermoscopy in suitable and right ways. If find any suspicious lesions, have medical attention promptly. In addition, keeping eyes on lesions and insisting on regular skin examinations are also important to keep the skin health.