Amelanotic melanoma is a type of
skin cancer
Skin cancers are cancers that arise from the skin. They are due to the development of abnormal cells that have the ability to invade or spread to other parts of the body. There are three main types of skin cancers: basal-cell skin cancer (BCC) ...
in which the cells do not make any
melanin
Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino ...
.
They can be pink, red, purple or of normal
skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other animal coverings, such as the arthropod exoskeleton, have different de ...
color, and are therefore difficult to diagnose correctly. They can occur anywhere on the body, just as a typical
melanoma can.
Often, amelanotic melanomas are mistaken for benign lesions, including
dermatitis
Dermatitis is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can ...
, benign neoplastic processes, or a different malignancy such as
basal-cell carcinoma
Basal-cell carcinoma (BCC), also known as basal-cell cancer, is the most common type of skin cancer. It often appears as a painless raised area of skin, which may be shiny with small blood vessels running over it. It may also present as a raise ...
or squamous-cell carcinoma.
A poor prognosis is associated with amelanotic lesions, partially due to the difficulty in achieving a diagnosis; however, metastatic amelanotic melanoma has a worse prognosis than other subtypes.
Survival after diagnosis of amelanotic melanoma was found in a 2014 seven-year study of 3,000 patients to be poorer than for pigmented melanoma, which was attributed to the more advanced stage at diagnosis due probably to difficulty of diagnosis. The study also suggested that amelanotic melanomas might grow faster than pigmented melanomas.
See also
*
Melanoma
*
List of cutaneous conditions
References
External links
Amelanotic melanomaentry in the public domain NCI Dictionary of Cancer Terms
Melanoma
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