Human renal cell carcinoma as a hormone-dependent tumor.

Abstract

Abstract On the basis of experimentally induced renal cancer and clinical, statistical, and epidemiological observations, it has been hypothesized that human renal cancer is hormone dependent. Hormone therapy for this neoplasm has been proposed. Recent knowledge of the mechanism of action of steroid hormones and demonstration of steroid receptors in the kidney of various experimental animals led us to investigate normal human kidney and human renal cell carcinoma for the presence of steroid receptors. By means of agar gel electrophoresis and of protamine sulfate assay techniques, estradiol receptors (ER) and progesterone receptors (PR) were sought in the cytosol fraction of renal cancer in 23 patients. ER was found in 61% and PR in 61% of the carcinomas studied: 39% of the tumors were positive for both ER and PR; 17% were negative for both ER and PR. ER and PR were also examined in the nuclear fraction of three renal cancers: estradiol nuclear receptor was found in two and progesterone nuclear receptor in three of the three tumors examined. These findings were considered strongly supportive of the hypothesis of the hormone dependence of human renal cancer. Progestational therapy, commenced after nephrectomy in 18 of the 23 patients investigated, was considered a useful adjuvant in 14 cases; 3 of 4 patients with receptor negative cancers did not respond favorably to progestins, while one is still alive more than 33 months after surgery. One patient with ER-positive and PR-negative tumor, given antiestrogenic therapy following nephrectomy, died after 8 months of treatment. The follow-up of the remaining patients is reported.