Little data exists in the medical literature describing the response of patients with inflammatory bowel disease (IBD) to abdominal and pelvic irradiation. To clarify the use of this modality in this setting, this study assesses the short- and long-term tolerance of 28 patients with IBD to abdominal and pelvic irradiation.

From 1970 to 1999, 28 patients with IBD (10 patients-Crohn's disease, 18 patients-ulcerative colitis) were identified and underwent external beam abdominal or pelvic irradiation. Mean follow-up time after radiation therapy was 32 months. Patients were treated either by specialized techniques (16 patients) to minimize small and large bowel irradiation or by more conventional approaches (12 patients). Acute and late toxicity was scored.

The overall incidence of severe toxicity was 46% (13/28 patients). Six of 28 patients (21%) experienced severe acute toxicity necessitating cessation of radiation therapy. Late toxicity requiring hospitalization or surgical intervention was observed in 8 of 28 patients (29%). One patient experienced both an acute as well as late toxicity. For patients undergoing radiation therapy by conventional approaches, the 5-year actuarial rate of late toxicity was 73%. This figure was 23% for patients treated by specialized techniques (p = 0.02).

Because of the potentially severe toxicity experienced by patients with IBD undergoing abdominal and pelvic irradiation, judicious use of this modality must be employed. Definition of IBD location and activity as well as careful attention to irradiation technique may allow treatment of these patients with acceptable rates of morbidity.