Feminizing Sertoli cell tumors associated with Peutz-Jeghers syndrome: an increasingly recognized cause of prepubertal gynecomastia.

Testicular sex cord tumors with annular tubules are an increasingly recognized cause of prepubertal gynecomastia typically accompanied by accelerated linear growth and advanced bone maturation. Serum estrogen levels may be elevated. Testicular ultrasound and biopsy are diagnostic, and mastectomy is indicated. Although these tumors can occur independently, causing gynecomastia in 10 percent of cases, they usually occur in patients with Peutz-Jeghers syndrome. In any Peutz-Jeghers syndrome patient developing gynecomastia, a testicular tumor should be sought. Conversely, because a significant proportion of all reported prepubertal gynecomastia patients have Peutz-Jeghers syndrome with testicular tumors, this syndrome must be considered for all young boys in whom the cause of gynecomastia is not otherwise apparent. When Peutz-Jeghers syndrome is suspected, gastroscopy, colonoscopy, and testicular biopsies can be performed under one anesthetic at the time of mastectomy.