Hormone-related tumors in transsexuals receiving treatment with cross-sex hormones

Objective: to assess the risk of development of hormone-related tumors in transsexuals receiving treatment with cross-sex hormones. Design: Description of cases of transsexuals who have developed a hormone-related malignancy observed in their own clinic or reported in the literature. Recommendations for early diagnosis and prevention are presented. Methods: Review of the literature in PubMed. Results: In male-to-female transsexuals receiving estrogen administration, lactotroph adenomas, breast cancer, and prostate cancer have been reported. In female-to-male transsexuals receiving treatment with testosterone, a single case of breast carcinoma and several cases of ovarian cancer have been reported. So far endometrial cancer has not been encountered though it remains a potential malignant development. Conclusions: There are so far only a few cases of hormone-related cancer in transsexuals. There may be an underreporting. The probability of a hormone-related turner increases with the duration of exposure to cross-sex hormones and the aging of the population of transsexuals.