A Comparison of Outcomes of Endoscopic Submucosal Dissection (ESD) For Early Gastric Neoplasms Between High-Volume and Low-Volume Centers: Multi-Center Retrospective Questionnaire Study Conducted by the Nagano ESD Study Group

Objective Outcomes of endoscopic submucosal dissection (ESD) for early gastric neoplasms at low-volume centers have been unknown, because all previous reports have studied in advanced single centers. The aim of this study was to compare ESD outcomes between high- and low-volume centers. Methods A retrospective questionnaire survey was conducted and 30 centers (96.8%) responded. The complete en-bloc resection rate (CERR) and the incidence of complications were analyzed. Early gastric cancer (EGC) was divided into three categories on the basis of pathological diagnosis-standard indication (SI), expanded indication (EI) and out-of-indication (OI). Results A total of 703 early gastric neoplasms (586 EGCs, 117 gastric adenomas) were treated with ESD from January to December 2005. The institutions that treated more than 30 cases a year were classified as high- volume centers, and those with less than 30 cases, low-volume centers. In SI, the CERRs at high- and low-volume centers were 92.1% and 91.1%, in EI, CERRs were 86.2% and 82.6% and in OI, CERRs were 80.3% and 88.0%. The perforation rates at high- and low-volume centers were 3.6% and 4.7%. The intra-operative bleeding rates at high- and low-volume centers were 0.26% and 0%, while the delayed bleeding rates were 0% and 0.63%. Conclusion There were no significant difference in the outcomes of ESD for early gastric neoplasms between high- and low volume centers.