Endocrine Abstracts

Pancreatic neuroendocrine tumors (NET) have always represented a complex dilemma for diagnostic imaging. This is mainly due to their small size and brought during the years to a complex range of diagnostic proposals. A correct preoperative detection and staging are mandatory in order to choose management options and to optimize surgical treatment. Endoscopic Ultrasound (EUS) has been claimed to be the best technique for imaging the pancreas, it allows.

High resolution images of the main pancreatic duct and surrounding parenchyma. One of the more relevant advantages of EUS compared with US, CT and MRI was indeed the superior parenchymal resolution, that gives reason for the results of several studies that established the superior sensitivity of EUS (98%) for the diagnosis of pancreatic tumors in comparison to all the other imaging modalities. The results of EUS were even better in small tumors, less than 3 or 2 cm, where sensitivity of US and CT decreased to only 29%. However the introduction of multidetector helical CT has today revolutionized the field of pancreatic imaging. More recent data on pancreatic NETs confirmed that the distance between helical-CT and EUS has nearly been annulled. EUS remains the best method for the detection of small pancreatic insulinomas and gastrinomas, but the first imaging modality to be used today in the suspicion of a pancreatic NET must be a multislice CT. EUS is needed as a second step in the diagnostic algorithm when CT shows negative or doubtful results. So the most effective method for revealing pancreatic NET is a combined imaging protocol that consists of both CT and EUS. The endosonographic pattern of these tumors is mainly represented by small focal hypoechoic, omogeneous, round lesions, with sharp margins, often hypervascular. Several studies have shown the high sensitivity and specificity of EUS in localizing endocrine tumors of the duodeno-pancreatic area. We demonstrated a correct localisation of pancreatic tumors in 86.7% of 23 cases surgically confirmed. In conclusion EUS is highly accurate in the detection of pancreatic neuroendocrine tumors and is cost effective when used early in the preoperative localization strategy. EUS decreased the need for additional invasive tests and avoided unnecessary morbidity and resource consumption.

EUS should play a primary role in preoperative localization and staging of these tumors.