Endoscopic Ultrasonography for Preoperative Diagnosis and Localization of Insulinomas

Abstract

Background: Endoscopic ultrasonography (EUS) is generally accepted as a sensitive method for the detection of small pancreatic tumors. We report our experience with EUS for preoperative imaging of insulinomas. Methods: Nine patients with clinical and biochemical signs of insulinoma were examined by EUS using a 7.5/12 MHz radial-scanning ultrasound endoscope prior to surgery. EUS outcome was evaluated on the basis of surgery (open or laparoscopic) and examination of the resected specimens. Results: Two EUS-negative patients appeared, by reassessment of clinical and biochemical data, not to have an insulinoma and were not operated on. EUS correctly imaged and localized five of seven insulinomas that were surgically removed. One isoechoic tumor in the pancreatic head and one pedunculated tumor connected to the caudal side of the pancreatic body were missed by EUS. EUS could demonstrate the size and shape of the imaged tumors, as well as their relationship to adjacent structures, such as the pancreatic duct, bile duct, and large vessels. Conclusions: Our experience with seven insulinomas accords with previous reports claiming EUS to be the method of choice for preoperative imaging and localization of pancreatic islet cell tumors.

• Endosonography
• Imaging
• Insulinoma
• Localization
• Pancreas
• Surgery