Multicenter Observational Study of Multimodal AI for Upper GI Mesenchymal Tumor Diagnosis

This study is using artificial intelligence to analyze ultrasound images (endoscopic ultrasound, or EUS) of tumors in the upper digestive tract to improve diagnosis — specifically to tell apart GISTs (gastrointestinal stromal tumors) from other similar-looking growths. **You may be eligible if...** - You are 18 years or older - You have a small tumor or lesion (subepithelial lesion) in your upper digestive tract found by endoscopy - You have completed an endoscopic ultrasound (EUS) examination - Your tumor has been diagnosed by tissue sampling or surgical removal - The quality of your EUS images meets the study's technical standards **You may NOT be eligible if...** - Your EUS images do not meet the required quality standards - You have not had a tissue diagnosis or your lesion has not been adequately evaluated - You are under 18 years old Talk to your doctor to see if this trial is right for you.