Feasibility and Safety of Endoscopic Full-Thickness Resection for Gastric Submucosal Tumors With Extraluminal Growth

Although endoscopic resection is an accepted technique for gastric submucosal tumors (SMTs), extraluminal tumors remain a challenging procedure with limited data. This study aimed to evaluate the efficacy and safety of endoscopic full-thickness resection (EFTR) for gastric SMTs with extraluminal growth.

Between June 2013 and December 2024, 102 patients undergoing EFTR for gastric SMTs with extraluminal growth were retrospectively included. Data on patient characteristics, clinical outcomes, and follow-up were analyzed.

The en bloc tumor resection rate was 95.1% and en bloc retrieval rate 92.2%. The mean lesion size was 2.6 ± 1.2 cm. The tumor growth pattern included predominantly extraluminal growth (79 cases) and completely extraluminal growth (23 cases). Postoperative adverse events included delayed bleeding (1 case), mucosal injury (2 cases), pneumothorax/hydrothorax (2 cases), and febrile episode (1 case). Multivariate analysis showed tumor size ≥ 3 cm (OR 2.748, 95% CI 1.312-5.527, p = 0.011) and irregular morphology (OR 3.684, 95% CI 1.582-8.574, p = 0.002) remained significant risk factors for piecemeal extraction. Tumor size ≥ 3 cm (OR 3.128, 95% CI 1.328-7.367, p = 0.009) and irregular morphology (OR 4.129, 95% CI 1.752-9.732, p = 0.001) were independent risk factors for prolonged operative times. No local recurrence or metastasis was detected during the mean follow-up period (31 ± 16 months and 32 ± 18 months, respectively).

EFTR is feasible and safe for gastric SMTs with extraluminal growth pattern, including lesions with completely extraluminal growth. Tumor size and shape impact the difficulty and safety of the procedure. Further validation in a prospective study is warranted.