Comparative analysis of late functional outcome following preoperative radiation therapy or chemoradiotherapy and surgery or surgery alone in rectal cancer.

PURPOSE: This study evaluates the anorectal and genitourinary function of patients treated by preoperative short-term radiotherapy (RT) or chemoradiotherapy (CRT) followed by surgery and surgery alone for rectal cancer.
METHODS: For this study, a total of 613 patients, who were identified from a prospective rectal cancer database, underwent anterior resection of the rectum between October 2001 and December 2007. Standardized questionnaires were used to determine fecal incontinence, urinary, and sexual function. Relevant clinical variables were evaluated using univariate and multivariate analyses. Independent predictors of functional outcome were identified by a binary logistic regression analysis.
RESULTS: The data of 263 (43 %) patients were available for analysis. On multivariate analysis, neoadjuvant RT (P < 0.01) and low anterior resection (LAR) (P = 0.049) were associated with fecal incontinence. In univariate analysis, fecal incontinence was linked to preoperative neoadjuvant treatment (RT and/or CRT vs. LAR) (P < 0.01). The hazard ratio for developing fecal incontinence was 3.3 (1.6-6.8) for patients who received RT. One hundred twenty-five patients (51.2 %) experienced urinary incontinence following surgery, the majority of whom were female (P < 0.01). On univariate analysis, male sexual function was associated with age (P < 0.01), ASA class (P = 0.01) and LAR (P = 0.01).
CONCLUSION: Multimodal therapy of low rectal cancer increases the incidence of fecal incontinence and negatively affects sexual function. The potential benefits of RT or CRT need to be balanced against the risk of increased bowel dysfunction when determining the appropriate treatment for individual patients with rectal cancer.