Risk factors for delayed bleeding after endoscopic submucosal dissection for colorectal neoplasms.

Purpose: Although delayed bleeding is a major complication of endoscopic submucosal dissection (ESD) for colorectal neoplasms, few reports have assessed the risk factors for delayed bleeding after colorectal ESD.

Methods: This study included 363 consecutive patients in whom 377 colorectal neoplasms were resected using ESD between April 2006 and August 2012. We classified patients and lesions into two groups on the basis of presence or absence of delayed bleeding and retrospectively compared the clinicopathological characteristics and clinical outcomes of ESD between the two groups.

Results: Delayed bleeding occurred in 25 (6.6 %) of 377 lesions, and all cases of delayed bleeding were successfully controlled by endoscopic procedures. With respect to patient-related factors, there was no significant difference between the groups in mean age, sex ratio, and current use of antithrombotic agents. With respect to lesion-related factors, there was no significant difference between the groups in mean lesion size, growth pattern, and mean procedure time (p = 0.6). Lesions located in the rectum (vs colon, p = 0.0005) and lesions with severe submucosal fibrosis (vs no or mild fibrosis, p = 0.022) were significantly related to delayed bleeding. Upon multivariate analysis, lesions located in the rectum (vs colon, odds ratio 4.19; p = 0.0009) were significantly related to delayed bleeding after colorectal ESD.

Conclusions: This study demonstrated that location of lesions in the rectum was a significant independent risk factor for delayed bleeding after ESD for colorectal neoplasms.