Natural History of Upper Gastrointestinal Subepithelial Tumors

Subepithelial tumors (SETs) of the upper gastrointestinal tract are increasingly detected as incidental findings, particularly in regions with gastric cancer screening programs.Although most SETs are small, asymptomatic, and benign, gastrointestinal stromal tumors (GISTs) and neuroendocrine tumors are malignant or potentially malignant.Given that conventional biopsy is often inadequate for these mucosa-covered lesions, small asymptomatic SETs are frequently managed with periodic endoscopic or endoscopic ultrasound surveillance rather than immediate histologic confirmation.The present review summarizes the natural history of upper gastrointestinal SETs from an organ-specific perspective.In the esophagus, where leiomyoma predominates, multiple long-term cohort studies have shown that the most lesions remain stable, supporting endoscopic surveillance for lesions unless malignancy is suspected.In the stomach, the most common site of GISTs, large cohort studies have reported size changes in < 10% of lesions (4.2-9.4%),whereas lesions suspected to be GISTs exhibit substantially higher progression rates (11.6-28.4%).In the duodenum, a relatively uncommon and anatomically challenging site, available data remain limited; however, existing studies suggest a low rate of progression.Reported risk factors for progression include a larger initial tumor size, irregular borders, mucosal abnormalities (erosion or ulceration), a lobulated morphology, and heterogeneous or cystic features on endoscopic ultrasound.Current guidelines focus largely on gastric SETs and GISTs.Careful initial evaluation to exclude lesions with malignant potential, followed by risk-stratified surveillance, remains the cornerstone of management.Nevertheless, further studies with long-term follow-up are needed to establish optimal surveillance strategies.