Virilizing Leydig cell adenoma of adrenal gland.

We describe the third report testosterone-producing, virilizing, adrenal Leydig cell adenoma, which was identified in a oophorectomized postmenopausal female patient. Light- and electron-microscopy demonstrated typical Leydig cell differentiation, including numerous intracytoplasmic and intranuclear Reinke crystals and rice-like bodies (elementary tubular inclusions). Testosterone production by the adenoma was demonstrated by the immunoperoxidase technique. We propose that adrenal Leydig cell adenomas arise as a result of ovarian gonadal stromal metaplasia associated with elevated follicle-stimulating hormone and luteinizing hormone in the postmenopausal female patient. Adrenal Leydig cell lesions must be considered in the virilized woman with elevated testosterone levels and normal levels of the adrenal androgens and their 17-ketosteroid metabolites.