Analysis of Natural History of Upper Gastrointestinal Subepithelial Tumors and Factors Related to Tumor Growth Demonstrated by Endoscopic Ultrasonography

ABSTRACT

BACKGROUND/AIMS: Small subepithelial tumors (SETs) are often found incidentally during esophagoduodenoscopy, and EUS is a useful tool for assessing SETs. This study aimed to evaluate the natural history of SETs and to clarify the predictive factors of growth using EUS. MATERIALS AND METHODS: We retrospectively investigated SETs less than 30 mm and identified the EUS features. A significant increase in SET size was defined as a lengthening of more than 25% of the longest diameter in the last follow-up EUS features compared with the initial study. RESULTS: A total of 99 patients with 105 upper gastrointestinal SETs were enrolled. The mean follow-up period for SETs was 22.8 months. Among the 105 SETs, 12 (11.4%) were significantly larger at follow-up. Univariate analysis revealed that the presence of hypoechoic areas was associated with significant SET growth (P=0.021). In multivariate analysis, the presence of hypoechoic areas (OR, 8.96; 95% CI, 1.89~42.54) and anechoic areas (OR, 7.85; 95% CI, 1.09~56.37) were related with significant growth of SETs. Six of the 12 SETs showing significant growth were removed, and identified as gastrointestinal stromal tumors. CONCLUSIONS: Majority of small SETs showed no significant increase during follow-up. Presence of hypoechoic areas and anechoic areas were associated with SET growth. Therefore, small SETs with hypoechoic area or anechoic area may be considered for regular follow-up in the clinical field.