External beam radiation monotherapy for localized or locally advanced prostate cancer

Abstract

Purpose: We report the treatment results and complications of external beam radiation monotherapy for localized or locally advanced prostate cancer patients. Methods: Fifty-four patients with T1b-3aN0(pN0)M0 prostate cancer were treated with external beam radiation monotherapy between 1989 and 2001 at four institutes. Results: During the 4-122 month follow-up period (median: 25 months), 11 (20%) patients experienced biochemical failure, including one with simultaneous local recurrence. The 2-year actuarial biochemical control rate was 85%. Univariate analysis showed that the clinical T classification (P = 0.01), Gleason score (P = 0.006), pretreatment PSA (P = 0.02) and PSA nadir value (P = 0.01) were associated with a higher probability of biochemical failure. Multivariate analysis using the Cox proportional hazards model demonstrated that only the PSA nadir value was a strong predictor of PSA recurrence (P < 0.01). Adverse events were mild and tolerable. No severe urinary or bowel complications were observed. Conclusions: External beam radiation monotherapy is effective for clinically organ-confined prostate cancer with a low incidence of severe complications in a mean follow-up period of 2 years. © 2003 Foundation for Promotion of Cancer Research.