LATE EFFECTS OF RADIATION-THERAPY ON THE GASTROINTESTINAL-TRACT

Late gastrointestinal complications of radiation therapy have been rec ognized but not extensively studied. In this paper, the late effects o f radiation on three gastrointestinal sites, the esophagus, the stomac h, and the bowel, are described. Esophageal dysmotility and benign str icture following esophageal irradiation are predominantly a result of damage to the esophageal wall, although mucosal ulcerations also may p ersist following high-dose radiation. The major late morbidity followi ng gastric irradiation is gastric ulceration caused by mucosal destruc tion. Late radiation injury to the bowel, which may result in bleeding , frequency, fistula formation, and, particularly in small bowel, obst ruction, is caused by damage to the entire thickness of the bowel wall , and predisposing factors have been identified. For each site a descr iption of the pathogenesis, clinical findings, and present management is offered. Simple and reproducible endpoint scales for late toxicity measurement were developed and are presented for each of the three gas trointestinal organs. Factors important in analyzing late complication s and future considerations in evaluation and management of radiation- related gastrointestinal injury are discussed.