Radiation-Induced Cancers of the Colon and Rectum-Analysis of Five Cases

Abstract

Purpose. Acute radiation injury may cause serious complications to the pelvic colon and rectum especially in patients with pelvic malignancies. There are considerable differences of opinion about the risk for the development of colorectal cancer following pelvic irradiation. We present five patients whose tumors were considered to be radiation-induced. Methods. A retrospective review of medical records was performed to identify colorectal cancer patients who had previously received radiotherapy following surgical treatment for their primary cancers. Results. Review of medical records revealed 5 patients (one male and four female). Their age ranged from 65 to 87 years, with an average of 73.4 years. Four patients had rectal cancer and one patient had sigmoid colon cancer. All of these patients had radiation therapy at least 10 years prior to the development of colorectal cancer. Three patients had received radiation therapy for cervical cancer, one for bladder cancer, and one for rectal cancer. One patient underwent low anterior resection, one abdominoperineal resection and three Hartmann's resections of the colorectal cancers. Conclusion. Irradiation may play a role in the development of colorectal cancer. Benefit of radiotherapy should be evaluated against the risk of development of cancer in the radiated bowel.