Late rectal and urinary toxicity from conformal, dose‐escalated radiation therapy for prostate cancer: A prospective study of 402 patients

Abstract

This study investigates the rate of late rectal and urinary toxicity from three-dimensional conformal radiation therapy (3DCRT) for localized prostate cancer. The influence of neoadjuvant androgen deprivation (AD) on toxicity rates was also examined. A total of 402 men at Liverpool and Westmead hospitals received radical 3DCRT for localized prostate cancer between 1999 and 2003. Patients received either 70 Gy or 74 Gy, according to their prognostic risk grouping and or date of commencing radiation therapy (RT). Late rectal and urinary toxicity data were collected prospectively using Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer criteria. The median follow up of this cohort was 43.5 months. At 36 months, the cumulative incidence of >or=grade 2 rectal and urinary toxicities was 6.7 and 17.5%, respectively. Peak prevalence of late urinary toxicity occurred at 36 months (9.5%), although late rectal toxicity was highest at 12 months (2.9%) from completion of 3DCRT. The use of AD did not cause additional late toxicities. Patients receiving 74 Gy did not experience significantly worse toxicities than the group receiving 70 Gy.