Almost everyone has pigmented spots on their skin. Most adults have approximately twenty-five moles – some have none and others have hundreds. Moles generally appear between childhood and the mid-twenties. Pigmented spots or moles present at birth or in the first year of life are called “congenital.” They seem to have a higher chance of becoming malignant; however, the exact percentages are in dispute. Certainly congenital moles should be evaluated and, in many cases, removed.
Moles appear during the early years. Most benign moles are small and symmetric, with even borders and bland coloration. Normally they do not itch, burn, or bleed. Moles which change, which become inflamed, or whose border and/or color is irregular should be evaluated. Despite advances in photography and digital imaging, the gold standard of evaluation remains biopsy with microscopic evaluation.
When examined under the microscope, a mole may be given one of three diagnoses:
Benign – This means there is nothing to worry about.
Atypical or dysplastic – These moles may appear somewhat unusual on the skin (asymmetric, large, or dark). Similarly, they appear unusual under the microscope. Some people have two or three atypical or dysplastic moles. Removal with small margins is considered adequate treatment. Some people have many moles which appear atypical both clinically and pathologically. That finding, especially when there is a family history of melanoma, can be a very strong risk factor for the future development of melanoma. Such patients must be followed closely and family members screened.
Malignant melanoma – This is a tumor that is formed of melanocytes (or mole cells). It may arise on normal skin or within a pre-existing mole. It may show the typical A, B, C, D features of Asymmetry, Border irregularity, Color variation, and Diameter larger than 6mm, BUT some melanomas may be small, non-pigmented and without typical features. When diagnosed and treated early, it is curable. When ignored, it can be fatal. Prognosis is based on the depth of the melanoma in the skin, certain laboratory tests, and in some cases, biopsy of sentinel lymph nodes. Treatment is determined, of course, by those variables. If caught early, a malignant melanoma may be cured by simple excision. If diagnosed later, radiation, chemotherapy, or vaccine therapy may be needed.
The number of malignant melanomas is increasing yearly. Early detection remains the best way to fight this disease. Knowledge of the family history and avoidance of sunburns is very important. Similarly, periodic self examination and total body evaluation by a professional is key to the early diagnosis and successful treatment of this potentially fatal disease.