A clinical, histologic, and follow-up study of genital melanosis in men and women

Background Genital melanosis may clinically mimic melanoma. Little is known about the potential risk for genital and nongenital melanoma in these patients. Objective In this retrospective cohort study, we analyzed clinical and histologic data from patients with genital melanosis to better characterize these lesions and the risk they confer for genital and nongenital melanoma. Methods In all, 41 patients were identified for a retrospective chart review and histologic analysis. Results Genital melanosis can clinically mimic melanoma but the typical age of onset is younger than for genital melanoma. A majority of lesions were found to stabilize or regress over time. Five patients were found to have a history of melanoma, only 1 of which was in the genital region. Lesions from these patients were more likely to show melanocytes with suprabasal movement (P = .0101) and to have a higher melanocyte count (P < .0462). Limitations We present a relatively small cohort of patients with an average follow-up of only 30.5 months. Conclusion Patients with genital melanosis, and in particular those with any level of histologic atypia in the genital melanosis lesion, may require careful total body skin examinations for the possibility of melanoma in any body site.