AimIatrogenic colonic perforation (ICP) is a rare serious complication of colonoscopy, where standard treatment is controversial. This study aimed to characterize diagnostic ICP (DICP) compared to therapeutic ICP (TICP) and determine the possible indication of endoscopic repair.MethodsWe studied patients with ICP over 7 years starting in 2011. Their demographics and data regarding perforation, treatment, and outcome were investigated by retrospective review of medical records, and the diagnostic and therapeutic groups were compared.ResultsAmong 29,882 patients who underwent colonoscopy, ICP was identified in 28 (0.09%: diagnostic, 15/24,758, 0.06%; therapeutic, 13/5124, 0.25%). A total of 56 patients (33 DICP and 23 TICP) including 28 referred cases were analyzed. Mean age was 62.3 ± 11.4 years, and 24 were men. Perforations occurred mostly in the rectosigmoid region and half were detected during or immediately after colonoscopy. Endoscopic treatment was successful in 22 cases and 34 required surgery. Mortality occurred in 4 (7.1%).Compared to TICP, DICP was more prevalent in females and rectosigmoid region and more frequently detected immediately (all p < 0.05); DICP tended to occur in older patients, be larger and have better chance of endoscopic repair.Regardless of type of ICP, female predominance, smaller perforation, more frequent immediate detection, and shorter hospital stay (all p = 0.01) were found in the endoscopic repair group.ConclusionDICP was more frequent in the rectosigmoid area in older women and could be detected immediately. Immediate detection and small perforation size could be important factors for endoscopic repair. Careful attention and gentle manipulation should be required.