Melanoma of Non-Sun Exposed Skin in a Man with Previous Prostate Cancer: Recognition of a Recently Confirmed Association

Abstract

Background: The association of an increased risk to develop melanoma in patients with prostate cancer has recently been confirmed. Purpose: The postulated etiologic relationship between prostate cancer and the subsequent occurrence of melanoma is discussed. Methods: A man with previous prostate cancer who developed melanoma on the plantar surface of his left great toe is described and the possibility of high levels of endogenous androgens promoting not only prostate cancer, but also increased risk of melanoma are reviewed. Results: Modification of the host immune response, alteration of chromosome telomere length, and/or imbalance of androgen level (presenting as severe teenage acne) are potential mechanisms whereby high levels of endogenous androgens may contribute to the association between prostate cancer and risk of melanoma. Conclusions: An increased surveillance for melanoma should be considered in prostate cancer patients. Complete skin examination in men who have had prostate cancer—especially in those individuals diagnosed with prostate cancer prior to age 68 years—should regularly be performed.