Chapter 22 - Inflammatory bowel disease–like conditions: radiation injury of the gut

Abstract

Columnar epithelia and small vasculature in the gastrointestinal tract are sensitive to radiation injury, leading to inflammation, bleeding lesions, strictures, fistulas, and postoperative anastomotic sinus. The source of radiation injury is not limited to external beam, and the injury to the bowel may also be induced by brachytherapy in the pelvic organs. While some endoscopic features of radiation enteritis, colitis, and proctitis overlap with that in Crohn’s disease and ulcerative colitis, others are predominantly seen in the radiation injury, such as spontaneous bleeding and telangiectasia lesions. In addition, clinical history helps differential diagnosis. The association between radiation and inflammatory bowel disease (IBD) is reflected in other aspects, including the impact of the radiation on the disease course and differential diagnosis of IBD in those with IBD-associated colorectal cancer or extraintestinal cancer.