Outcomes of simultaneous endoscopic submucosal dissection for synchronous multiple gastric neoplastic lesions: a retrospective comparative study.

Simultaneous endoscopic submucosal dissection (ESD) is occasionally used in synchronous multiple gastric neoplastic lesions (SMGL). Therefore, we aim to evaluate the safety and efficacy of simultaneous ESD for SMGL compared with ESD for single lesions. A total of 1058 patients who received ESD from November 2006 to September 2019 were retrospectively evaluated in this study, including 997 single gastric epithelial lesions treated by single ESD (unifocal group) and 125 SMGL from 61 patients treated by simultaneous ESD (multifocal group). The mean procedure time was 49.2 ± 41.30 min and 89.5 ± 66.33 min in unifocal group and multifocal group, respectively (p < 0.001). There was no significant difference in postoperative stenosis rate (1.0% vs. 0.0%, p = 1.000), intraoperative bleeding (endoscopic resection bleeding-c3 grade) rate (0.5% vs. 1.6%, p = 0.696), postoperative bleeding rate (1.3% vs. 0.0%, p = 0.461), and perforation rate (0.9% vs. 1.6%, p = 0.449) between the two groups. In addition, en block resection rate (p = 0.825), complete resection rate (p = 0.856) and curative resection rate (p = 0.709) were comparable between the two groups. During the follow-up, the local recurrence rate per patient: p = 0.363; per lesion: p = 0.235) was not significantly different between the two groups, however, the cumulative incidence of metachronous lesions after treatment was significantly higher in the multifocal group than the other group (10.0% vs. 3.2%, p = 0.004). Simultaneous ESD is safe and effective in the treatment of SMGL. However, separate ESD is recommended for SMGL with longer procedure time. Besides, the metachronous gastric neoplastic lesions should be paid attention to during follow-up.