Breast adenocarcinoma complicating Kallmann's syndrome.

Carcinoma of the breast is relatively rare among men, accounting for less than 1% of all malignancies. An increased risk has been associated with benign breast diseases, such as gynecomastia, Klinefelter's syndrome, testicular disorders, exogenous estrogen use, radiation, or a family history of male or female breast cancer. To date, hypogonadotrophic hypogonadism has never been associated with male breast cancer. We report here the first case of breast cancer coexisting with Kallmann's syndrome in a 66-year-old man.