Background: This prospective study was designed to evaluate the safety and efficacy of submucosal tunneling endoscopic resection (STER) for small (≤3 cm) upper gastrointestinal (GI) subepithelial tumors (SETs) originating from the muscularis propria (MP) layer.
Methods: Between August 2011 and February 2013, a total of 85 patients with upper GI SETs originating from the MP layer were treated with STER. The key steps were as follows: (1) locating the tumor by injection of methylene blue or indigo carmine and then creating a submucosal tunnel from 5 cm above the tumor between the submucosal and muscular layers; (2) resecting the tumor by endoscopic resection techniques; (3) closing the mucosal incision site with several clips after the tumor is removed.
Results: Of the 85 SETs, 60 were located in the esophagus, 16 in the cardia, and 9 in the stomach. STER was successfully performed in all cases (success rate: 100 %). The mean tumor size was 19.2 mm. The mean procedure time was 57.2 min. The average hospital stay after the procedure was 5.9 days. Pathological diagnosis of the tumors were leiomyoma (65/85), gastrointestinal stromal tumor (GIST) (19/85), and calcifying fibrous tumor (1/85). During the procedure, eight patients developed pneumothorax, subcutaneous emphysema, and/or pneumoperitoneum. These patients recovered after conservative treatment. The rate of all complications was significantly higher for lesions originating in the deeper MP layer (70 %) than in the superficial MP layer (1.3 %; p < 0.001). The total complication rate for different histological diagnoses was also significantly different (26.3 % for GISTs, 4.6 % for leiomyomas, 0 % for calcifying fibrous tumors, p < 0.05). No residual or recurrent tumors were detected during the follow-up period (median: 8 months).
Conclusions: Submucosal tunneling endoscopic resection appears to be a feasible, safe, and effective procedure for treatment of small (≤3 cm) upper GI SETs originating from the MP layer.