Mucosal, genital, and unusual clinical variants of melanoma.

To demonstrate the need for a through cutaneous and mucosal examination, we discuss and illustrate the spectrum of mucosal melanomas and unusual clinical variants of melanoma. Although cutaneous areas exposed to sunlight are most vulnerable, melanomas can occur in any site on the skin or mucous membranes. Pigmented nevi as well as mucosal and labial melanotic macules are lesions that simulate oral mucosal melanomas but are not associated with such a poor prognosis. In contrast, the 5-year survival rate for patients with malignant melanomas of the oral mucosa is only 5%. Similarly, the prognosis is poor for patients who have malignant melanomas of the vulva, vagina, male genitalia, or anorectal area; most patients with such lesions are 50 years of age or older. Subungual and plantar areas are common sites of malignant melanomas, and involvement of the eyelid margin portends a poor prognosis. Other rare variants-desmoplastic, amelanotic, and polypoid malignant melanomas-are associated with local recurrences and metastatic lesions. Early diagnosis is the key to proper treatment and improved survival rate for patients with these unusual variants of melanoma. Increased awareness of the wide variety of clinical features of melanoma should lead to earlier diagnosis.