The diagnosis and preoperative localization of gastrointestinal endocrine tumors by endoscopic ultrasonography

UNLABELLED: Around 30% of the gastroenteropancreatic endocrine tumors (GPET) cannot be preoperatively identified by the common diagnostic imaging techniques. The aim of this retrospective study was to present our experience in the diagnosis and localization of GPET by endoscopic ultrasonography (EUS) performed prior to surgery and compare this with a review of the literature. PATIENTS AND METHODS: Twenty patients suspected of having specific hormonal syndromes were correlatively explored with US, CT, MR, angiography, octreoscan and radial EUS with Olympus GFUM3/EUM3 and GF-UM20/EUM 20 and 30. Eleven cases were males (55%) and 9 (45%) females with a mean age of 60 years (range: 40-80 years). Of the 20 patients, 14 had endocrine 16 tumors in the pancreas and 6 tumors in the gastrointestinal tract. In 6 patients no tumors were found and were therefore used as a control group. Of the 20 patients, 14 underwent surgery confirming the existence of GPET in 12 cases. RESULTS: The diagnostic sensitivity and precision of the EUS were of 75 and 78%, respectively, with these percentages being higher to those obtained with other imaging techniques. The specificity was 83%. All these values were slightly lower than the mean obtained on review of the literature. Two pancreatic tumors of less than or equal to 1 cm were detected which had not been previously diagnosed with US, CT and MR. In two cases the exact situation was not determined. Echo-endoscopic exploration of the pancrease could not be completely performed in two cases (10%), one pancreatic carcinoma and one double pancreatic gastrinoma which was gastrectomized. Endoscopic ultrasonography is a good preoperative technique for detecting GPET and in the evaluation of small sized tumors it may surpass other imaging techniques. The usefulness of EUS as a second exploration following US has been suggested for the diagnosis and localization prior to surgery.