Effects of preoperative chemoradiotherapy on anal sphincter functions and quality of life in rectal cancer patients

Deterioration of anorectal function after long-course preoperative chemoradiotherapy combined with surgery for rectal cancer is poorly defined. We conducted a prospective study to evaluate the acute and long term effects of preoperative chemoradiotherapy on anorectal function and quality of life of the patients. There were 26 patients in surgery group and 31 patients in preoperative chemoradiotherapy group. Anorectal function and quality of life of the patients were assessed by anorectal manometry, incontinence score, quality of life questionnaire. Significant lower resting pressures in both groups and lower maximal squeeze pressures in the preoperative chemoradiotherapy group were observed after postsurgical evaluations compared with the paired pretreatment ones. In the surgery group, both the Wexner continence score, FIQL score, and the rectoscopy score were comparable before and after surgery, whereas significant worsening in the Wexner score was observed in the preoperative chemoradiotherapy group postoperatively (P < 0.01). Significant reduction in anal canal resting pressures and squeeze pressures, Wexner score, and FIQL score were observed immediately after the completion of preoperative chemoradiotherapy. Significant lower maximal squeeze pressures and worsening of the Wexner scores were observed in the preoperative chemoradiotherapy group compared to the surgery group during the postoperative assessments (P < 0.05 and P < 0.01, respectively). Both total mesorectal excision and preoperative chemoradiotherapy may adversely affect the anorectal function. Careful selection of the patients who will benefit from neoadjuvant therapy and identifying the patients with a high risk of developing functional problems may help to improve functional outcomes for the treatment of rectal cancer.