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 J anuary 2005 through J uly 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 = 1.224–13.831). 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 = 1.472–102.939). 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.