STUDIES ON THE URINARY STEROIDS IN BILATERAL GYNECOMASTIA

Studies were made on the urinary estrogens and 17-ketosteroids in bilateral gynecomastia. Twenty one cases of gynecomastia were classified into 3 types by estrogen excretion patterns. The daily excretion of estrogen was less than 11.4μg (normal upper limit) in type A (9 cases) and over 11.4μg in type B (9 cases); a partial blocking was observed in the conversion of estradiol-17β and estrone to estriol and 16-epiestriol in type C (3 cases). In 10 out of 17 cases of gynecomastia, the ratio of etiocholanolone plus androsterone to 11-oxygenated 17-ketosteroids was less than 3. A normal value of the ratio varied from 3 to 10. The ratio of etiocholanolone to androsterone was more than 3 in 2 cases. A normal value ranged from 0.5 to 2. A total amount of 17-ketosteroids was less than a normal range in half the cases of gynecomastia studied. Thus, in some cases of gynecomastia, it is suggested that breast stimulation is brought about by an increased secretion and/or a decreased rate of inactivation of estrogens, and a decreased secretion of gonadal androgens and/or dehydroepiandrosterone may enhance the action of estrogens on mammary tissues.