Primary melanoma arising in the genitourinary tract is rare and poorly characterized.

We sought to describe the epidemiology of genitourinary melanoma in the United States.

Incident case and population data were obtained for genitourinary melanoma from the Surveillance, Epidemiology, and End Results 13 Registries Database between 1992 and 2012.

A total of 817 patients with genitourinary melanoma were identified; most cases occurred in the vulva. The incidence of genitourinary melanoma was much higher in women (1.74/1 million person-years) than men (0.17/1 million person-years). The highest rates occurred among non-Hispanic white women aged 85 years and older. Five-year melanoma-specific and overall survival were poor at 52.4% and 36.3%, respectively. Predictors of poor survival were increasing age, black race, and female sex.

The study population is small, therefore some rates reported may be unstable. In addition, cutaneous, mucosal, and other extracutaneous surfaces of the genitourinary tract cannot be reliably distinguished in Surveillance, Epidemiology, and End Results. Furthermore, melanomas may be underreported to cancer registries.

From 1992 to 2012, genitourinary melanoma was 10 times more common in women than men. Survival was poor in women compared with men, which is different from cutaneous melanoma where women have a survival advantage.