Objective      By analyzing the endoscopic and endosonographic features of upper gastro intestinal stromal tumors and their relation with tumor invasion risks

as well as following-up the clinical outcomes of patients

to evaluate endoscopy measures for prediction of tumor invasion risks and different treatment choices.       Methods      The clinical data of 292 patients with upper gastrointestinal stromal tumors diagnosed by endoscopic ultrasound (EUS) in our institute from March 2003 to December 2011 were analyzed retrospectively. The surgical and endoscopic resection specimens were subjected to pathological examination to clarify its invasion risk. The relation between the endoscopic and endosonographic features and the malignant potential was analyzed. Some patients were followed up to observe the changes in the tumors.       Results      EUS features of tumor size

surface

echo

shape and boundary showed statistically significant relation to tumor invasion risks. Tumors larger than 3 cm

especially with mucosal ulceration

non-oval shape

irregular extraluminal border and heterogeneous echo texture indicated moderate or high tumor invasion risks. Tumors smaller than 3 cm

with smooth surface

homogeneous hypoecho

regular shape and clear boundary suggested low tumor invasion risks. For non-surgical patients

follow-up results (average 24 months) showed that the tumor growth rates were 0.8%

8.8% and 12.5% of tumor size ≤1 cm group

tumor size 1 to 2 cm group

and tumor size 2 to 3.5 cm group

respectively.       Conclusion      The endoscopic and endosonographic features of upper gastrointestinal stromal tumors can be used to predict the invasion risk. Tumors with size not greater than 2 cm have low malignant potential and can be treated conservatively with regular clinical follow-up. The tumors with size 2 to 3 cm have low to medium malignant potential

and can be treated with surgical and endoscopic resection or close follow-up. The tumors with size greater than 3 cm have high malignant potential

and need to be treated with surgical or endoscopic resection.