Sertoli Cell Tumor Causing Prepubertal Gynecomastia in a Boy with Peutz-Jeghers Syndrome: The Outcome of 1-Year Treatment with the Aromatase Inhibitor Testolactone

Abstract Peutz-Jeghers syndrome (PJS) is a rare disorder characterized by benign intestinal hamartomatous polyps and mucocutaneous pigmentation, and with an increased risk for intestinal and extra-intestinal neoplasms. Sertoli cell tumors in boys with PJS have been increasingly recognized as a cause of prepubertal gynecomastia. However, an association between nephrocalcinosis and PJS has not been reported before. We report on a 7.25-year-old boy with PJS, bilateral gynecomastia, Sertoli cell tumor and nephrocalcinosis, and present the outcome of 1-year treatment with the aromatase inhibitor testolactone. The patient presented with bilateral breast and testis enlargement, and mucocutaneous pigmentation. Testicular ultrasound revealed parenchymal multiple microcalcifications. Histopathological examination was consistent with Sertoli cell tumors. Nephrocalcinosis due to idiopathic renal hypercalciuria was also detected. The aromatase inhibitor testolactone was begun in an attempt to prevent acceleration in skeletal maturation. One-year treatment with testolactone reduced the breast base diameter from 7 to 3 cm, and bone age advanced 1.2 years during this period. Our case demonstrates that waiting for the effect of aromatase inhibitors on gynecomastia before making a decision for mastectomy may be a reasonable option. We also consider that the association between PJS and nephrocalcinosis may be a coincidence.