Analysis of Factors Associated with Bleeding After Endoscopic Treatment of Colon Tumor

Abstract

Aim: Endoscopic resection has become the most popular and most promising treatment for polyps and early colorectal cancers. Although endoscopic resection is generally safe, bleeding, in addition to perforation, is the most serious complications arising from endoscopic resection. The proportion of bleeding after endoscopic resection may occurred up to 0.1-2.2% of cases. It is important to examine factors that may predict clinically bleeding after endoscopic resection. To evaluate the clinical characteristics of colon tumor which has high incidences of bleeding after endoscopic treatment, we performed case-control study in which tumor morphology, size, location and method of endoscopic treatment were examined. Methods: There were 40 post-endoscopic treatment bleeding cases in our database consisting of 14,381 polyps which were removed by hot biopsy, polypectomy and endoscopic mucosal resection (EMR) from June 1995 to September 2002 at our hospital. In addition, we randomly selected no-bleeding cases as a controls (n = 160) matching age and gender to bleeding cases from our database. We investigated the morphology, the size, the location of lesions (rectum, sigmoid, descending, transvers, ascending and cecum) and resection technique in these two groups and analyzed which of these factors are associated with the risk of bleeding. In addition, we studied days from endoscopic treatment to bleeding for bleeding cases. Results: From these bleeding cases, 85% were male with a median age of 57. The proportion of pedunculated polyps in the bleeding group was significantly higher than those in control group (p < 0.05). The size of lesions in the bleeding group was significantly larger than those in control group (p < 0.01). Lesions located in the ascending colon has the higher incidence of bleeding than those of control group (p < 0.05). The proportion of lesions which were removed by EMR in the bleeding group was significantly higher than those in control group (p < 0.01). Multivariate analysis of factors influencing the bleeding revealed that the significant factors was size (p < 0.0001). Bleeding occurred within 3 days (55.0%) in most cases and within 9 days in all cases. Conclusions: The size of the lesion was the most important factor for bleeding. Therefore, clips or coagulation forceps on the cut surface or vessels after endoscopic resection might be useful to prevent the bleeding. In addition, we should monitor the patients for at least 9 days after endoscopic resection.