Metabolism of testoterone and related steroids in metastatic interstitial cell carcinoma of the testis.

Interstitial cell carcinoma of the testis is a singu- larly rare steroid-producing cancer. Of the seven reported cases (1-7), urinary 17-ketosteroid (17- KS) excretion was high in the four cases in which it was measured. Abelson, Bulaschenko, Trom- mer, and Valdes-Dapena (7) fractionated the uri- nary 17-ketosteriods and corticoids in one recently reported case. There is, however, no comprehen- sive study of either the production of androgens or related steroids by this tumor. We have had the opportunity to study a patient with metastatic interstitial cell carcinoma, and we have examined the androgens and several related steroids. From these data, we have concluded that interstitial cell carcinoma resembles virilizing adrenal carcinoma in its pattern of biosynthesis of C-19 steroids and 21- deoxypregnane analogues. The high testosterone 1