Cyproterone acetate, testosterone, LH, FSH, and prolactin levels in plasma after intramuscular application of cyproterone acetate in patients with prostatic cancer.

Five patients with prostatic carcinoma (stages T3N0M0) were injected intramuscularly with 300 mg of cyproterone acetate (CPA) (Androcur-Depot) at weekly intervals. The concentrations of CPA, testosterone, LH, FSH, and prolactin in plasma after the first, third, and fifth injection were measured by specific radioimmunoassays. After five injections of Androcur-Depot, CPA levels were slightly higher than in previous determinations, suggesting that a balance between active substance release from the depot and excretion could be achieved after eight to twelve injections, with only slightly higher levels of active substance attained. Testosterone levels clearly were reduced after the first injection of CPA, but the lowest values were registered only after three injections. Plasma concentrations of FSH and LH were slightly diminished, whereas the prolactin level increased after CPA therapy.