Consequential late effects after radiotherapy for prostate cancer - a prospective longitudinal quality of life study

Background: To answer the question if and to which extent acute symptoms at the end and/or several weeks after radiotherapy can predict adverse urinary and gastrointestinal long-term quality of life (QoL). Methods: A group of 298 patients has been surveyed prospectively before (time A), at the last day (B), two months after (C) and >one year after (D) radiotherapy using a validated questionnaire (Expanded Prostate Cancer Index Composite). A subgroup of 10% with the greatest urinary/bowel bother score decrease at time D was defined as patients with adverse long-term QoL. Results: Subgroup and correlation analyses could demonstrate a strong dependence of urinary/bowel QoL after radiotherapy on urinary/bowel QoL before radiotherapy. In contrast to absolute scores, QoL score changes (relative to baseline scores) did not correlate with pretreatment scores. Long-term changes could be well predicted by acute changes. Patients reporting great/moderate bother with urinary/bowel problems at time C reported to have great/moderate bother at time D in >= 50%, respectively. In a multivariate analysis of factors for adverse long-term urinary and bowel QoL, score changes at time C were found to be independent predictors, respectively. Additionally, QoL changes at time B were independently predictive for adverse long-term bowel QoL. Conclusions: Consequential late effects play a major role after radiotherapy for prostate cancer. Patients with greater and particularly longer non-healing acute toxicity are candidates for closer follow-up and possible prophylactic actions to reduce a high probability of long-term problems.