Prolactinoma induced by estrogen and cyproterone acetate in a male-to-female transsexual

Objective: To report a case of a microprolactinoma in a male-to-female transsexual treated with estrogens and cyproterone acetate. Design: Case report. Setting: Endocrinology unit in a university hospital. Patient(s): A 33-year-old male-to-female transsexual with prolactin level of 10 ng/mL. Intervention(s): Treatment with equine-conjugated estrogens (2.5 mg/day, orally) and cyproterone acetate (100 mg/day, orally) during 6 months. Main Outcome Measure(s): Her levels of prolactin were repeatedly found to be elevated to a maximum of 133 ng/mL, and magnetic resonance imaging (MRI) revealed a pituitary mass of 5 x 4 x 4 mm. Result(s): Discontinuation of the cross-sex hormone treatment did not reduce the levels of prolactin. The use of dopaminergic-agonist therapy normalized them and reduced the size of the microadenoma. After sex-reassignment surgery, she was treated with low-dose estradiol transdermal patches and presented normal levels of prolactin and appropriate levels of 17 beta-estradiol and testosterone with a stable image in MRI. Conclusion(s): We report a case of prolactinoma after treatment with equine-conjugated estrogens and cyproterone acetate. We recommend long-term follow-up observation consisting of a periodic evaluation of prolactin levels and any symptoms suggestive of hyperprolactinemia to detect as early as possible complications derived from cross-sex hormone therapy. (Fertil Steril (R) 2010;94:1097.e13-e15. (C) 2010 by American Society for Reproductive Medicine.)