Role of endoscopic ultrasonography in the localization of insulinomas and gastrinomas.

We have previously found selective venous sampling to be the most sensitive method to localize otherwise occult functioning endocrine tumors. However, recently we have used endoscopic ultrasonography (EUS) as the initial and in some cases the only localization study in the preoperative evaluation of proven insulinomas and of selected cases of gastrinoma.All patients referred between April 1993 and April 1994 with a subsequently confirmed...