Acute and late toxicity in radical radiotherapy for bladder cancer

To evaluate the incidence, severity and kinetics of acute and late toxicity from bladder and bowels in patients with bladder cancer treated with radical radiotherapy.

The retrospective analysis was based on 487 patients with T2, T3 bladder cancer, treated with radiotherapy between 1975 and 1995. The pelvis was irradiated electively in 303 patients; in the remaining patients, the bladder alone was treated. The mean total radiation dose to the bladder was 65.5 Gy. Various schedules of protracted, conventional and accelerated radiotherapy were used. The influence of selected factors on maximum acute toxicity and late toxicity was assessed. The kinetics of acute toxicity was also evaluated. The median follow-up was 76 months.

Seven patients did not complete treatment due to excessive acute toxicity. The incidence of grade >or=3 acute bladder and bowel toxicity was 5 and 3%, respectively. The actuarial, 5-year incidence of grade >or=3 late bladder and bowel toxicity was 12 and 3%, respectively. The most important factors influencing acute toxicity were: T-stage (P=0.004) for the bladder and pelvic irradiation (P=0.044) and dose intensity (P=0.000) for the bowels. The latency of both early bladder and bowel toxicity was correlated with dose intensity. The most important factor influencing late bladder toxicity was acute toxicity score (P=0.000). Late bowel toxicity was also influenced by acute bowel toxicity (P=0.04).

The severity of acute bowel toxicity is related to pelvic irradiation and dose intensity. The severity of acute bladder toxicity depends on T-stage. The increase in dose intensity is associated with shorter latency to maximum acute bladder and bowel toxicity. The severity of acute bladder and bowel toxicity influences the risk of late effects from those organs.