Rectal bleeding after radiation therapy for prostate cancer: endoscopic evaluation.

Abstract

To analyze the frequency and clinical importance of proctitis and hematochezia after radiation therapy for prostate cancer. Of 63 patients with prostate cancer treated with curative intent by a single radiation oncologist between July 1, 1993, and December 31, 1997, 30 were asymptomatic, but 33 had heme-positive digital rectal examination (DRE) results or hematochezia at routine follow-up. Twenty-six of these patients underwent endoscopy of the sigmoid colon or colon for evaluation of these symptoms. Median doses of 60.0 Gy at postoperative radiation therapy and 68.4 Gy at definitive radiation therapy were delivered to four fields daily by using blocking customized on the basis of computed tomographically documented evidence of disease. The Fisher exact test and the Kaplan-Meier method were used to analyze the results. The frequency of rectal bleeding approached 80% at 3 years after radiation therapy in definitively treated patients. Only 14 patients had proctitis: eight as the only sign, and six in association with other disease. Six patients had other disease without proctitis, and four patients had normal examination findings. The frequency of rectal bleeding in the presence of proctitis was similar to that in the presence of other disease (Fisher exact test, P =.68). Hematochezia or positive DRE findings are frequent sequelae of definitive radiation therapy for prostate cancer; however, causes other than proctitis are often documented at endoscopy. Symptomatic individuals warrant rigorous evaluation to rule out serious coexistent disease.