Missed synchronous gastric neoplasm with endoscopic submucosal dissection for gastric neoplasm: Experience in our hospital

Aim Endoscopic submucosal dissection (ESD) has been widely accepted as a less invasive treatment for early gastric cancer and adenoma, but research on missed synchronous gastric neoplasm (SGN) with ESD has been limited. In the present study, we aimed to investigate the incidence and characteristics of missed SGN during follow-up endoscopy in patients who have undergone ESD. Method We investigated the clinicopathological features of 602 patients and gastric neoplasms treated by ESD from January 2005 through July 2009 at our institution. We defined any second neoplasm found within 1 year after ESD as a missed SGN. Results Out of 602 patients, 12 (2.0%) had missed SGN. Among the 12 missed SGN, seven (58.3%) cases were carcinomas. All cases of missed synchronous gastric cancer (SGC) wereexclusively discovered in the posterior wall of the stomach (7 of 7 cases, 100%, P?=?0.016). Missed SGN were more frequently observed when the primary gastric neoplasm was adenoma (4.0% vs 1.0%; OR?=?4.114; 95% CI?=?1.22413.831). Furthermore, the risk of missed SGC increased 12-fold in the primary gastric adenoma group compared to the primary gastric carcinoma group (2.9% vs 0.24%; OR?=?12.308; 95% CI?=?1.472102.939). Conclusion Endoscopists need to make an effort to find SGN, especially when they carry out ESD for an adenoma, which is a less serious lesion. The important blind spot in screening endoscopic examination before ESD is the posterior wall of the upper third and middle third of the stomach.