The progression rate and risk factor analysis of small gastric subepithelial tumors: a systematic review and meta-analysis.

Background And Aims: Small gastric subepithelial tumors (SETs) in the stomach can be managed through surveillance or resection. However, it is still controversial how often the lesion would progress if left untreated. This study aimed to evaluate the progression rate of small SETs and identify risk factors influencing tumor growth.

Methods: PubMed, Cochrane Library, Web of Science, and Scopus were searched for relevant studies until March 2023. Patient information, endoscopic features of SETs, and surveillance information were extracted from each included study. A random-effects model was applied along with subgroup and sensitivity analyses.

Results: Based on 14 studies with 5405 SETs smaller than 3.5 cm, the annual incidence of size increase was 4.0 (95%CI 2.2-5.8) per 100 person-years, and the overall incidence was 12.8% (95%CI 8.3%-17.3%) across a surveillance duration of 51.3 ± 16.9 months. The predicted risk factors for tumor growth included ≥ 1 cm lesion size (1-2 cm vs. < 1 cm, OR 2.61, 95%CI 1.80-3.79; and > 2 cm vs. 1-2 cm, OR 1.25, 95%CI 0.87-1.81), origin in the muscularis propria (OR 2.09, 95%CI 1.41-3.10), mucosal change (OR 3.27, 95%CI 1.95-5.50), irregular margin (OR 3.16, 95%CI 1.15-8.69), and hypoechoic pattern (OR 3.06, 95%CI 1.34-7.00).

Conclusions: Most small gastric SETs, particularly those smaller than 1 cm, did not increase in size during surveillance. Special attention should be given to lesions larger than 1 cm, originating from the muscularis propria, or exhibiting mucosal change, irregular margin, and hypoechoic pattern.