Antiandrogen monotherapy: a new form of treatment for patients with prostate cancer

Abstract

Nonsteroidal antiandrogens are generally used in conjunction with castration as combined androgen blockade. However, the changing profile of patients with prostate cancer has made monotherapy with a nonsteroidal antiandrogen an attractive alternative therapeutic approach, offering potential quality-of-life benefits over conventional treatment modalities. Of available antiandrogens, monotherapy with bicalutamide has been most extensively evaluated. Combined data from 2 studies at a median follow-up time of 6.3 years revealed no statistically significant difference in overall survival between bicalutamide 150-mg monotherapy and castration in patients with nonmetastatic locally advanced disease. In patients with metastatic disease, there was a statistically significant difference (6 weeks) in overall survival in favor of castration. Bicalutamide monotherapy is associated with significant quality-of-life benefits (sexual interest and physical capacity), with preliminary data suggesting that the risk of osteoporosis may also be reduced by bicalutamide 150-mg monotherapy compared with castration. In general, bicalutamide is well tolerated, with a predictable adverse-effect profile. Breast pain (40%) and gynecomastia (49%) are the most common adverse events seen during monotherapy with this drug. In summary, the availability of bicalutamide 150-mg monotherapy broadens treatment options for men with locally advanced prostate cancer, offering a viable and attractive alternative to castration in this patient population. Ongoing studies will determine the role of bicalutamide in the treatment of localized disease.