Factors Affecting The Results of Endoscopic Ultrasound-Guided Fine Needle Aspiration In Subepithelial Lesions of The Gastrointestinal Tract

Aim: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is a reliable diagnostic method to discriminate gastrointestinal subepithelial lesions (SEL). We aimed to evaluate the factors affecting of EUS-FNA procedure's diagnostic success in SEL.Method:Between May 2010-March 2020, all patients who underwent EUS-FNA were retrospectively evaluated. Factors effecting success rate (number of passes, needle size, lesion size, lesion localization, endoscopist's experience and presence of on-site cytopathologist) were investigated.Results:A total of 170 procedures were performed. SEL localization was 36.5% (n=62) esophagus, 55.9% (n=95) stomach. The mean lesion size was 26.5 ± 14.5 mm. Fourty one percent of lesions were <20 mm. In 115 (67.6%) of procedures, cytopatology was diagnostic and most common were spindle cell tumors (SCT) (n=42, 24.7%), followed by gastrointestinal stromal tumors (GIST) (n=31, 18.2%) and leiyomyommas (n=21, 12.4%). EUS-FNA success was higher in SEL >20mm (p=0.02) and endoscopist's experience (p = 0.001). Lesion's localization, layer and echogenicity, needle size, number of passes didn't affect success rate. The lesion size >20 mm (P=0.01), endoscopist's experience (P=0.003) and presence of cell block (P=0.02) were independent predictors for diagnostic success.Conclusions:EUS-FNA procedure is an effective method, lesion size, endoscopist's experience and presence of cell block increases the yield of cytological diagnosis in SEL.