Risk of bleeding after endoscopic submucosal dissection for colorectal tumors in patients with continued use of low-dose aspirin

Although Japanese guidelines proposed by the Japan Gastroenterological Endoscopy Society for endoscopic submucosal dissection (ESD) for colorectal tumors recommend continued use of low-dose aspirin (LDA), this strategy is controversial. It was our practice to interrupt LDA therapy 5-7 days before ESD until December 2010, when we instituted the new guidelines and performed ESD without interrupting LDA therapy. The aim of the present study was to confirm the validity of the noninterrupted use of LDA inpatients undergoing ESD for colorectal tumors. We studied 582 consecutive patients with 609 colorectal tumors who underwent ESD at Hiroshima University Hospital between January 2006 and July 2014. The patients comprised three groups: LDA-interrupted group (13 patients with 13 colorectal tumors), LDA-continued group (28 patients with 31 colorectal tumors), and no anticoagulant/antiplatelet group (541 patients with 565 colorectal tumors). The en bloc resection rate was 100 % (13/13) in the LDA-interrupted group and 90.3 % (28/31) in the LDA-continued group. Incidences of poor bleeding control during the procedure and bleeding after the procedure were 7.7 % (1/13) and 15.4 % (2/13) of patients, respectively, in the LDA-interrupted group, and 3.2 % (1/31) and 16.1 % (5/31) of patients, respectively, in the LDA-continued group. No patients experienced ischemic events in the perioperative period. Our data suggest that continued use of LDA increased the risk of bleeding after ESD for colorectal tumors compared with nonuse of anticoagulant/antiplatelets. No significant difference was seen between the LDA-continued group and the LDA-interrupted group.