Diagnostic Accuracy of Preoperative Diagnostic Procedure in the Assessment of Lymph Node Metastases by NF-PanNENs

Pancreatic Neuroendocrine Neoplasms (PanNEN) are a heterogeneous group of neoplasms that arise from the endocrine cells of the pancreatic gland. Non-functioning (NF-PanNEN) represents the most common forms and do not produce syndromes due to hormonal hypersecretion. Several prognostic factors have been demonstrated for NF-PanNEN. The presence of nodal metastasis and lymph node ratio are widely considered predictors of disease-free survival and even the number of positive nodes has been found to be associated with recurrence. In addition to traditional imaging exams, diagnostic work-up should include a Positron Emission Tomography/CT with 68Ga labeled somatostatin analogues, which have shown a high sensitivity and specificity while 18F-FDG PET can be associated for evaluating the possible presence of a high-grade component. Moreover, pancreatic endoscopic ultrasound (EUS) is usually part of the preoperative staging both for imaging details and cytological sampling. Therefore an accurate identification of nodal metastases preoperatively may have important implications for the extent of surgical resection and lymphadenectomy and even for a prognostic outcome. In this study the investigators will evaluate prospectively the accuracy of these diagnostic exams in detecting the lymph node status. Patients with sporadic NF-PanNEN who are candidates for surgical resection will undergo CE-CT scan, 68Ga DOTATOC (and eventually 18F-FDG) PET/MRI and EUS with FNA/B. Reference standard for defining the presence of nodal metastases is represented by pathological examination on the specimen.