High‐dose continuous‐infusion fosfestrol in hormone‐resistant prostate cancer

Abstract

Background. The initial treatment of advancedstage prostate cancer is total androgen deprivation. Autonomous proliferation of primarily or secondarily hormonal unresponsive cells may explain the development of hormone‐refractory status. The median survival of patients with hormone‐resistant disease is short; there is no standard regimen of chemotherapy. Methods. Fosfestrol or diethylstilbestrol diphosphate and its metabolites have cytotoxic activity in hormone‐refractory prostatic cell lines. Pharmacokinetic studies have shown that fosfestrol metabolites have a short half‐life that supports the use of long‐term infusion in the clinic. Results. A review of the literature shows that highdose fosfestrol induces no objective response, a greater than 50% tumor marker decrease in 50% of patients, a subjective improvement in 75% of patients, and cardiovascular complications in 5% of patients. The median survival time of patients is 5 months after the onset of treatment. Conclusions. An exact evaluation of the role of high‐dose estrogens requires additional investigation. Copyright © 1993 American Cancer Society