Clinical relevance of plasma testosterone and prolactin changes in advanced cancer of prostate treated with diethylstilbestrol or estramustine phosphate.

We have investigated a group of 30 patients with newly diagnosed metastatic carcinoma of the prostate who were randomly assigned to receive, as primary treatment, either diethylstilbestrol (DES) or estramustine phosphate (Emcyt). Clinical response was assessed following the guidelines of the National Prostatic Cancer Project and the Eastern Cooperative Oncology Group. Effective reduction in the levels of androgens was noted in all patients in both groups regardless of response. During the follow-up period (ranging between 2-5 years) relapses were noted despite the presence of androgen levels at or below castrate values. The most relevant endocrine observation was the detection of early elevations in serum prolactin in a majority of patients. It was noted, however, that those patients in whom hyperprolactinemia did not occur or appeared only briefly at the beginning of therapy, experienced a prolonged, symptom-free survival. Persistent hyperprolactinemia, on the other hand, carried an ominous prognosis. The differences in survival between normoprolactinemic and hyperprolactinemic groups carried statistical significance.