Case of feminizing interstitial cell tumor of the testicle. clinical and biochemical evaluation

A man aged 42, with increasing clinical signs of feminization over a 2-yr period and a testicular tumor, was studied. An interstitial cell tumor of the testicle was removed. Urinary steroid excretion and plasma androgen concentrations during both the control and postoperative periods were not indicative of the source of the causative agent. The tumor was homogenized and incubated with pregnenolone- 7α-H³ with the isolation products including 19- hydroxyandrostenedione and minor quantities of 2 phenolic compounds, estrone and 16-ketoestrone. A definite answer to the source of estrogens could not be demonstrated via the urinary estrogen excretion or tumor biosynthesis. Possible explanations for the clinical findings, laboratory results and incubation data are discussed.