Natural Course and Long-Term Outcomes of Gastric Subepithelial Lesions: A Systematic Review

Background/Objectives: Gastric subepithelial lesions (SELs) are often incidentally detected during endoscopic examinations, with most patients being asymptomatic and lesions measuring <20 mm. Despite their generally indolent nature, certain SELs, such as gastrointestinal stromal tumors, require resection. Current guidelines recommend periodic surveillance; however, the natural course and long-term outcomes of gastric SELs have not been sufficiently investigated. This systematic review aimed to synthesize evidence on the progression, growth rate, and risk factors associated with gastric SELs to inform clinical management strategies. Methods: A comprehensive search of PubMed was conducted for peer-reviewed studies published between January 2000 and November 2024. Eligible studies included original studies on the follow-up and progression of gastric SELs. Non-English articles, reviews, case reports, and unrelated topics were excluded. In total, 277 articles were screened, with 15 additional articles identified through manual screening. Ultimately, 41 articles were included in the analysis. The study protocol is registered in PROSPERO (CRD42024614865). Results: Large-scale studies reported low growth rates of 2.0–8.5% over 2.0–5.0 years, while smaller studies reported a broader range of growth rates of 5.4–28.4%. The factors contributing to these discrepancies include patient selection, follow-up duration, and growth criteria. Risk factors for lesion size increase include larger initial lesion size, irregular margins, heterogeneous echo patterns, and certain tumor locations. Conclusions: These findings underscore the need for individualized management strategies based on lesion size, imaging characteristics, and risk factors. The close monitoring of high-risk lesions is crucial for timely intervention. Standardized growth criteria and optimized follow-up protocols are essential for improving clinical decision making and patient outcomes.