Predictive Factors of Subepithelial Tumor and Gastrointestinal Stromal Tumor in the Patients with Upper Gastrointestinal Subepithelial Lesions

Background/Aims: Differentiating subepithelial tumor (SET) from non-neoplastic gastrointestinal subepithelial lesion (SEL) and gastrointestinal stromal tumor (GIST) from leiomyoma are very important for proper management. This study was conducted to analyze factors that could predict the presence of SET and GIST in patients with upper gastrointestinal (UGI) SELs. Methods: A total of 527 patients were diagnosed with UGI SELs endosonographically at Gyeongsang National University Hospital from January 2008 to June 2013. Among these patients, histologic diagnosis was made in 84 patients. Data were collected by retrospectively reviewing the medical records. Variables that could differentiate neoplastic from non-neoplastic SELs and GIST from leiomyoma were analyzed. Results: Among 84 patients with SELs, 64 (76.2%) had SETs including GIST (42.9%) and leiomyoma (19.0%). The patients’ mean age (p=0.047), peak age distribution (p=0.047), proportions of patient ≥50 years (p=0.015), and number of proper muscle-originated lesions (p=0.001) were higher in neoplastic than non-neoplastic group. There were no significant differences in gender (p=0.195), size (p=0.266) and echogenicity (p=0.051) of the lesions. Older age (57.7 vs. 47.0 years, p=0.049), age ≥50 years (p=0.016), location in gastric body (p0.001), and proper muscle origin (p=0.003) were significantly related to the presence of GIST compared to leiomyoma. Multiple regression analysis showed that the patients’ age ≥50 years, size ≥30 mm, and proper muscle-origin of lesion were independent predictors of SET; however, there were no predictive factors that could differentiate GIST from leiomyoma. Conclusions: In patients with SEL, the possibility of having SET should be considered for patients ≥50 years with UGI SELs ≥30 mm that arise from the proper muscle. Thorough monitoring and aggressive management is warranted for those with gastric muscular SET since factors predictive of GIST are lacking. (Korean J Gastroenterol 2014;64:189-197)