Endoscopic Ultrasound-guided Needle-based Confocal Laser Endomicroscopy for Diagnosis of Gastric Subepithelial Tumors

Derivative study Inclusion Criteria: * patients aged from 18 to 75 years, with gastric subepithelial tumors ≥ 2 cm Exclusion Criteria: * Previous EUS-FNA performed within the past 3 months, and usual contraindications to EUS-FNA, such as serous cardiopulmonary diseases, severe coagulopathy dysfunction, impaired kidney function * Extramural structures, vascular lesions or cystic masses were visible by EUS * Pregnancy or breastfeeding * Known allergy to fluorescein sodium * Inability to provide informed consent Validation study Inclusion Criteria: * patients aged from 18 to 75 years, with gastric subepithelial tumors ≥ 1 cm Exclusion Criteria: * Previous EUS-FNA performed within the past 3 months, and usual contraindications to EUS-FNA, such as serous cardiopulmonary diseases, severe coagulopathy dysfunction, impaired kidney function * Extramural structures, vascular lesions cystic masses or lipoma were visible by EUS * Pregnancy or breastfeeding * Known allergy to fluorescein sodium * Inability to provide informed consent