Natural Course of Gastric Subepithelial Tumor

Kim, Sung Eun; Park, Moo In

Abstract

Subepithelial tumor (SET) is a protruding elevated mass covered with normal appearing mucosa, and is a relatively common finding during esophagogastroduodenoscopy. Recently, the incidence of asymptomatic small SETs is increasing due to esophagogastroduodenoscopy for national gastric cancer screening program in Korea. Unfortunately, the management of SETs is still controversial because the natural history of SETs is hardly known. There are only few studies about the natural history of SETs, especially in the stomach. According to studies, the overall rate of increased size of gastric SETs is 5.4~28%. Tumor size, age, non-upper area of the stomach, and detection of anechoic lesion or echogenic foci on endoscopic ultrasound (EUS) are related with size increase in gastric SETs. Gastrointestinal stromal tumors (GISTs) are one of the most important tumors, and the prognosis of GISTs is closely connected with tumor size, mitotic count, and organ location. Among them, tumor size is relatively easy to approach with esophagogastroduodenoscopy or EUS. Asymptomatic gastric SETs < or =2 cm show a benign clinical course and the malignant potential of them is nearly 0%, even if the gastric SETs are confirmed as GISTs. However, asymptomatic gastric SETs >2 cm, < or =5 cm might be considered for detailed pathologic diagnosis and treatment, if the possibility of GISTs cannot be ruled out. Well-designed, prospective studies are required for more accurate management of SETs.