Melanoma of the Female Reproductive Tract, With Emphasis on Differential Diagnosis
Pigmented vulvar lesions, present in 10% of white American women, include diffuse hyperpigmentation, nonmelanocytic pigmented lesions, nevi, and melanoma. Melanoma of the vulva is uncommon, mostly located on the glabrous skin with initial symptoms of bleeding, pruritus, or a groin mass. The fourth is amelanotic, the clitoral area and labia majora being the most common primary sites. Almost all have a vertical growth phase. Melanomas in the glabrous skin apparently emerge de novo as preexisting nevi are uncommonly associated and if so, are on hairy skin. Unlike melanomas on sun-exposed sites, mucosal melanomas do not frequently harbor an activating mutation of BRAF. But the vulva, traditionally protected from sun exposure, may be at increased risk in this age of nude sunbathing and tanning beds. Diagnostic pitfalls include vulvar nevi, nevi on lichen sclerosus, pigmented Bowen disease, extramammary Paget disease, etc. Diagnostic accuracy is enhanced by full knowledge of the clinical setting. Primary vaginal, cervical, and ovarian melanomas are rarer still. The prognosis of vulvar melanoma is worse and recurrence rate higher than for cutaneous melanomas. Yet survival, stage by stage, is not markedly different, recommending regular examinations, especially for elderly women who predominate, and prompt biopsy of suspicious lesions.