4757 Role of endoscopic ultrasonography in therapeutic decision making and in following-up gastrointestinal submucosal tumors and extraluminal compressions.

Purpose: EUS has been proved to be the best method to diagnose upper GI ST and to differentiate them from EC.However no follow-up studies are available up to now. The aim of our work was to compare prospectively histopathological data of tumors removed by surgery to EUS results and to perform a follow-up of ST identified by EUS. Methods: 269 consecutive patients (pts) (143 men, mean age 58,9 years) suspected of having upper GI ST or EC at routine endoscopy, underwent EUS with a rotating sector scanner (Olympus GF-UM2/UM3/UMQ130). Histological data available for 53 pts (47 underwent surgery, 2 had a polipectomy and 4 had a biopsy) were compared to EUS diagnosis. Furthermore we followed-up other 108 pts with ST by EUS or endoscopy. Results: performing EUS in 269 pts, we found 289 lesions (in 5 pts no lesion was confirmed by EUS). 206 lesions were diagnosed as ST mostly due to leiomyoma (118) and lipoma (20) and 69 as EC mostly due to vascular structures (25) and gallbladder (11); 5 resulted intramucosal lesions and 4 could not be better defined by EUS. In 6/6 cases of EC EUS diagnosis was confirmed at surgery. In 46 cases of SL we have histological diagnosis on resected specimens. EUS diagnosis was histologically confirmed in 33/41 (80.4%) and a good agreement was found about tumor size. 82 pts underwent EUS follow-up (mean 23.1±18.5 months) without showing any critical change in tumor size or echopattern. 31 pts remained asymptomatic with lesions unchanged at endoscopic follow-up.CT, US or barium radiography gave no additional information. Conclusions: EUS represent a major adjunct to the available imaging armamentarium for diagnosing and differentiate ST from EC. It is also the most cost-effective method for following-up GI ST. No significant changes were demonstrated in ST size or echopattern in the medium/long period even in tumors greater than 3 cm. Furthermore EUS has shown a good accuracy in predicting the nature of ST and EC as compared to histopathology and can be of value in identifying the best candidates to surgery.