Biclutamide ("Casodex") 150 mg as Adjuvant to Radiotherapy in Localized or Locally Advanced Prostate Cancer
Ryan Smith, MD
University of Pennsylvania Cancer Center
Last Modified: November 4, 2001
Presenter: C. Tyrrell
Affiliation: Plymouth Oncology Centre, Plymouth, United Kingdom
Biclutamide (Casodex) is often used as adjuvant therapy in patients who have biochemical failure after definitve therapy. This is a study to evaluate the use of biclutamide as an immediate therapy or as adjuvant to therapy of curative intent in non-metastatic prostate cancer.
Biclutamide was used as an immediate adjuvant therapy in this study. Although there was a significant risk reduction with biclutamide, it was employed in a patient population that has a low risk of disease progression. With a control group freedom from progression of 80%, this translates into a number of patients treated who probably did not need the hormonal therapy. There was no data on disease control and control of symptoms when patients failed and other forms of adjuvant therapy was used (i.e.-LHRH agonists). In this group of patients, overall survival was 94% at 3 years, while historically, OS is often 96-98% at ten years. Therefore, these may be more advanced or aggressive than indicated. The side effect profile is concerning with 85% complaining of gynecomastia/breast pain, though the severity was not presented. The 9% impotence rate is very low, when even with primary therapy alone (XRT or RP), impotence is often in the range of 40%. Therefore, this is likely grossly underestimated. Multivariate analysis was not done, so it is not known if "traditional" indicators of disease aggressiveness (PSA, Gleason Score, T stage) would explain the disrepencies between the two groups. Follow-up of 3 years is very short for a study of prostate cancer and longer follow-up is needed.