Clinical impact of submucosal tunneling endoscopic resection for the treatment of gastric submucosal tumors originating from the muscularis propria layer (with video)

Submucosal tunneling endoscopic resection (STER) can be adequately adopted as an effective treatment for submucosal tumors (SMTs) originating from the muscularis propria (MP) layer at the esophagus and cardia. However, it has been seldom used for gastric SMTs. Our purpose was to evaluate the clinical impact of STER for gastric SMTs arising from the MP layer. Thirty-two patients with gastric SMTs from the MP layer were retrospectively included. The main outcome measurements were complete resection rate, adverse events, local recurrence, and distant metastases during follow-up. Of the 32 lesions, 12 were located in the gastric corpus close to the cardia, 3 in the gastric fundus close to the cardia, 6 in the lesser curvature of the gastric corpus, and 11 in the greater curvature of the gastric antrum. STER was successfully performed in all patients with en bloc resection of tumors. The mean tumor size was 2.3 cm (range 1.0-5.0 cm). The complete resection rate was 100 %. The operation time ranged from 25 to 125 min (mean 51.8 min). All complications related to STER were successfully managed with conservative treatments. Local recurrence or distant metastasis did not occur during a follow-up period of 6-32 months. STER is a safe and effective therapeutic strategy for eligible gastric SMTs originating from the MP layer. Submucosal tunneling in the stomach may be more challenging than that in the esophagus, but does not increase procedure-related adverse events or prevent successful STER for eligible gastric SMTs.