Genital melanosis and lentiginosis is a benign condition that is characterized by irregular pigmentation on the genital mucosa. Both females and males may be affected. In females, the vulvar mucosa is the most commonly involved site.

Vulvar melanosis and lentiginosis affects all age groups but favors perimenopausal women. When seen in children, it may be associated with Bannayan-Riley-Ruvalcaba syndrome, lentiginosis perigenito-axillaris syndrome, Carney complex, LEOPARD syndrome, Laugier-Hunziker syndrome, Dowling-Degos disease, or Peutz-Jeghers syndrome. Vulvar melanosis may also represent post-inflammatory hyperpigmentation from trauma, lichen sclerosus, or lichen planus.

The pathogenesis of genital melanosis and lentiginosis is unknown. It is postulated that hormonal influence on melanocytes could play a role. A history of cutaneous melanoma may be associated with an increased risk of genital melanosis and lentiginosis.

Vulvar melanosis and lentiginosis follows a benign course. Malignant transformation has not been reported. However, the diagnosis may be a marker of subsequent cutaneous melanoma development at other sites.