POSSIBLE BONE-PRESERVING CAPACITY OF HIGH-DOSE INTRAMUSCULAR DEPOT ESTROGEN AS COMPARED TO ORCHIECTOMY IN THE TREATMENT OF PATIENTS WITH PROSTATIC-CARCINOMA

BACKGROUND. Treatment of prostatic disease with GnRH agonists or by or chidectomy affects bone mass negatively. Estrogen treatment has benefi cial effects on bone mass in women and might hypothetically have a bon e preserving capacity also in patients with prostatic cancer. METHODS. We followed serum markers for bone and collagen metabolism and sex st eroids for 18 months in patients with prostatic cancer treated by orch idectomy (N = 13) or by single-drug parenteral polyestradiol phosphate (240 mg intramuscularly every second week for the first two months, a nd then every fourth week; N = 17). RESULTS. Total and free testostero ne reached castration levels within 1.5 months of estrogen treatment. Four patients developing progressive disease and/or signs of metastasi s were excluded from the analysis. In the remaining patients, serum os teocalcin, procollagen IIIP (PIIINP), procollagen (PICP), and the cros slinked carboxyterminal telopeptide of type I collagen (ICTP) increase d significantly over time following orchidectomy (N = 11). Serum osteo calcin and PICP decreased significantly over time during estrogen trea tment (N = 15). Treatment values of all four markers were significantl y lower in estrogen-treated than in orchidectomized patients. CONCLUSI ONS. The changes in serum bone and collagen markers indicate an increa sed bone turnover in orchidectomized subjects. The opposite pattern wa s found in the estrogen-treated patients, indicating a reduced turnove r. Estrogens may also have a bone mass-preserving capacity in elderly males with prostatic cancer. (C) 1997 Wiley-Liss, Inc.