Background/Aims The clinical course after endoscopic management of delayed postpolypectomy bleeding (DPPB) has not been clearly identified. with additional modalities such as injection methods were more common in the rebleeding positive group (67/291, 23.0% vs. 12/17, 70.6%; P<0.001). Multivariate analysis showed a large number of clips and combination therapy were self-employed risk factors for rebleeding. All the rebleeding instances were successfully handled by repeat endoscopic hemostasis. Conclusions Endoscopic hemostasis is effective for the management of DPPB because of its high initial hemostasis rate and low rebleeding rate. Endoscopists should cautiously observe individuals in whom a 31690-09-2 manufacture large number of clips and/or combination therapy have been used to manage DPPB because these may be related to the severity of DPPB and a higher risk of rebleeding. Keywords: Colonoscopy, Postpolypectomy bleeding, Clip, Rebleeding Intro Most colorectal cancers develop from adenomatous polyps. Colonoscopic polypectomy can remove most colorectal polyps efficiently, and reduce the risk of colorectal malignancy.1,2,3 Despite its performance in the prevention of colorectal malignancy, polypectomy is not completely safe because it is associated with complications such as bleeding and perforation.4 Postpolypectomy bleeding happens in 0.3% to 6.1% of colonoscopic polypectomy cases.5,6,7,8,9,10 Postpolypectomy bleeding is generally classified as either immediate/early postpolypectomy bleeding (IPPB) or delayed postpolypectomy bleeding (DPPB). IPPB is usually defined as bleeding that evolves immediately after resection of FGFR4 polyps during the colonoscopy process. Because endoscopists can directly detect IPPB, most instances can be handled endoscopically during the colonoscopic process. 6 DPPB is definitely defined as bleeding that evolves after the end of colonoscopic polypectomy. Most DPPB is definitely detected when individuals complain of hematochezia several hours to several days after colonoscopic polypectomy. The incidence of DPPB is definitely reported to be 0.2% to 2.2%.6,7,8,11,12 Although most endoscopists apply endoscopic hemostasis to manage DPPB, clinical results of endoscopic management have not been thoroughly investigated. Thus, the aim of our study was to assess the medical results after endoscopic hemostasis for DPPB. We also evaluated the rate of recurrence of DPPB and risk factors for recurrence of bleeding after initial endoscopic hemostasis. METHODS 1. Individuals All individuals who underwent colonoscopic and/or sigmoidoscopic bleeding control for DPPB at Asan Medical Center between January 2010 and February 2015 were included in this study. DPPB was defined as hematochezia and/or melena happening within 14 days of colonoscopic polypectomy. Techniques included chilly snare polypectomy, injection aided polypectomy (endoscopic mucosal resection, EMR), endoscopic piecemeal mucosal resection (EPMR), endoscopic submucosal resection (ESD), and ESD with snaring (cross ESD). Patients were classified into two organizations based on the event of rebleeding. The rebleeding positive group 31690-09-2 manufacture was defined as those who presented with hematochezia 31690-09-2 manufacture and/or melena after the initial successful endoscopic hemostasis and required repeat hemostatic interventions. The rebleeding bad group was defined as those who did not show further hematochezia and/or melena after the initial successful endoscopic hemostasis. 2. Review of Clinical Data We retrospectively examined medical records and endoscopy reports with photos. Demographic data such as age, gender, laboratory findings, comorbidities, and use of medications including antiplatelet providers (aspirin, clopidogrel) and anticoagulants (warfarin, heparin) were investigated. Colonoscopic features of each resected polyp such as the size, location, endoscopic morphology, histological analysis, and colonoscopic polypectomy methods were analyzed. Info on endoscopic hemostasis such as the endoscopist’s encounter (staff vs. fellow) and the endoscopic hemostasis methods were also reviewed. Clinical results after endoscopic hemostasis, including success or failure of endoscopic hemostasis, complications, recurrent bleeding, and overall performance of repeat interventions, were further investigated. Success of endoscopic hemostasis was defined as the cessation of bleeding after endoscopic interventions such as clipping. The Institutional Review Table of our center authorized the protocol of this study. 3. Statistical Analysis Statistical analyses were performed by using SPSS version 21.0 (IBM Corp., Armonk, NY, USA). Continuous variables are reported as means with SDs and compared using College student t-test. Categorical data were analyzed using Fisher precise test. Multivariate.