Hormone treatment and sex steroid receptors in metastatic renal cell carcinoma: Report of a multicentric prospective study

Twenty-eight patients with metastatic renal cell carcinoma entered a multicentric prospective study to evaluate the response to high-dose medroxyprogesterone acetate (MPA) and testosterone in MPA failures in relation to sex steroid receptors. No objective remission was seen in the 24 evaluable patients, and only disease stabilizations of short duration were achieved in one-third of treated patients. Stabilizations achieved with second line testosterone were all seen in patients unresponsive to MPA. Receptor studies demonstrated that estrogen, progesterone, or androgen receptors were found in low concentrations and in only 6 of 23 tumors (26%) and 13 normal tissue samples (56%). Surprisingly, no disease stabilization was achieved in patients positive for receptors. It can be concluded that the occasional objective responses to hormone therapy reported in the literature may have been due to some cytotoxic effect of hormone therapy rather than to a true hormonal mechanism.