Bicalutamide monotherapy preserves bone mineral density, muscle strength and has significant health-related quality of life benefits for osteoporotic men with prostate cancer

Abstract

Objectives: • To evaluate changes in bone mineral density (BMD), body composition, muscle strength and health-related quality of life (HRQL) during bicalutamide (150 mg) monotherapy in osteoporotic patients with non-metastatic locally advanced prostate cancer. Osteoporosis is prevalent in men presenting with prostate cancer and also a common side effect of treatment with luteinizing hormone-releasing hormone agonists, which are associated with decreased BMD and loss of lean body mass and suppress testosterone, unlike bicalutamide, which results in an increase in serum testosterone and oestrogen levels.

Patients and methods: • Forty-two men with non-metastatic locally advanced prostate cancer and osteoporosis (T-score ≤-2.5) were treated with bicalutamide (150 mg) monotherapy. BMD was measured at baseline and 1 year. HRQL was assessed 3-monthly using the RAND 36-Item Health Survey and University of California Los Angeles Prostate Cancer Index questionnaires. Bone turnover markers, liver function tests, prostate-specific antigen, testosterone, oestradiol and haemoglobin were measured at baseline, at 3 weeks and 3-monthly thereafter. Arm anthropometry and dynamometry assessed fat mass, skeletal muscle mass and quadriceps strength.

Results: • BMD was maintained (+2.1% lumbar spine, +1.2% total hip and +1.1% forearm). Prostate-specific antigen decreased by 88% at 3 months. Testosterone and oestradiol had increased at 1 year by 58% and 42%, respectively. No increase in bone turnover markers was seen over 1 year. Quadriceps muscle strength was maintained. General and prostate cancer-specific HRQL were maintained throughout the study, with no significant reductions in physical or sexual function. Adverse events included breast pain and gynaecomastia.

Conclusions: • Bicalutamide preserves BMD, muscle strength and HRQL in osteoporotic men with non-metastatic locally advanced prostate cancer. It provides an alternative to medical castration for well informed men at high fracture risk and those wishing to retain physical and sexual activity, with luteinizing hormone-releasing hormone agonists being reserved for those failing to respond or relapsing.

Trial registration: ClinicalTrials.gov NCT00551044.