The incidence and clinical consequences of treatment-related bowel injury

Objective: To assess the frequency and clinical features of treatment-induc ed bowel injury in rectal carcinoma patients receiving perioperative extern al beam radiotherapy (EBRT), The frequency of and factors associated with t reatment-induced intestinal injury have previously not been well quantified for rectal cancer patients. Postoperative adjuvant chemoirradiation is rec ommended for Stage II and III rectal cancers, making such data of significa nt interest. Methods and Materials: The records of 386 consecutive patients undergoing r adiotherapy with or without chemotherapy (CT) for rectal carcinoma between 1981-90 were reviewed. Eight-two patients were excluded for receiving nonth erapeutic EBRT or modalities other than EBRT, Results: Symptomatic acute treatment-related enteritis (within 30 days of E BRT +/- CT) was diagnosed in 13 patients, 3 of whom developed chronic bowel injury. Chronic treatment-related enteritis was identified in 18 patients and reoperation was required in 17 (5% of the 304 patients with complete fo llow-up). Chronic proctitis was documented in 38 patients, including 3 pati ents with small bowel injury. The probability of developing treatment-induc ed bowel injury at 5 years following treatment was 19%, Variables associate d with an increased risk of bowel injury using multivariate analysis were t ransanal excision (p = 0.002), escalating radiation dose (p = 0.005), and i ncreasing age (p = 0.01). Twenty of the affected patients required operativ e treatment, and 2 deaths resulted from treatment-induced enteritis, Conclusion: Patients with rectal carcinoma treated with EBRT +/- CT have th e risk of developing treatment-induced bowel injury. The pelvic radiation d ose should be limited to less than or equal to 5040 cGy unless small bowel can be displaced. Reperitonealization of the pelvis, or other surgical meth ods of excluding the small intestine should be used whenever possible. (C) 1999 Elsevier Science Inc.