Gonadotroph cell adenoma of the pituitary in a women with long-standing hypogonadism

A 57-year-old woman, with long-standing hypogonadism secondary to irradiation of the ovaries, was found to have a pituitary tumor which was removed and investigated by histology, immunocytology and electron microscopy. Histologically, the tumor corresponded to a chromophobe, slightly PAS positive adenoma and the immunoperoxidase stain revealed the presence of both FSH and LH in the cytoplasm of the adenoma cells. The structural features of the adenoma cells resembled those of FSH cells in the nontumorous adenohypophysis. We thus believe that pituitary adenomas consisting of gonadotrophin-producing cells occur and that these may produce both FSH and LH. The relation between the gonadotrophin-producing adenoma and the preceding hypogonadism is uncertain.