Objective: The authors assessed the long-term effect of postoperative chemoradiotherapy on bowel function.
Summary background data: Adjuvant postoperative radiation therapy, often combined with chemotherapy, is being used increasingly often for rectal carcinoma. However, the long-term effect of this treatment on bowel function has not been investigated.
Methods: The records were reviewed of all patients undergoing anterior resection for rectal carcinoma 2 to 5 years previously. During this period, patients with Astler-Coller stage B2 or C tumors generally were given postoperative radiation therapy with chemotherapy, whereas those with earlier stage tumors were not. To minimize possible confounding factors that may have been more common in the group receiving chemoradiotherapy and that may affect bowel function, extensive exclusion criteria were used, such as invasion of contiguous organs, local or distant metastases, use of a dysfunctioning stoma, and anastomotic or pelvic complications. One hundred remaining patients were suitable for inclusion in the study and participated in a telephone questionnaire; 41 patients had postoperative chemoradiotherapy, and 59 did not.
Results: The two groups were well matched for sex, level of anastomosis, and length of follow-up, although the group receiving chemoradiotherapy was slightly younger. The group that had chemoradiotherapy had more bowel movements per day than the group that did not have radiation therapy (median 7 vs. median 2, p < 0.001); the former group had "clustering" of bowel movements more often (42% vs. 3%, p < 0.001), had nighttime movements more often (46% vs. 14%, p < 0.001), had occasional or frequent incontinence more often (39% and 17% vs. 7% and 0%, p < 0.001), wore a pad more often (41% vs. 10%, p < 0.001), and were unable to defer defecation for more than 15 minutes more often (78% vs. 19%, p < 0.001). The group that had chemoradiotherapy also had stool of liquid consistency, used antidiarrheal medications, had perianal skin irritation, were unable to differentiate stool from gas, and needed to defecate again within 30 minutes of a movement significantly more often than the group that did not receive chemoradiotherapy.
Conclusion: Adjuvant postoperative chemoradiotherapy for rectal carcinoma has a major long-term detrimental effect on bowel function.