Preoperative imaging with contrast-enhanced computed tomography (CE-CT), endoscopic ultrasonography (EUS), and 68Gallium-DOTATOC positron emission tomography (68Ga-DOTATOC PET) for the detection of nodal metastases (N+) in sporadic nonfunctioning pancreatic neuroendocrine tumors (NF-PanNETs). Accurate preoperative detection of N+ in NF-PanNETs is crucial for surgical planning. Lymph node (LN) metastases in NF-PanNETs are difficult to detect, and little research has been done on the efficacy of various imaging modalities. Patients diagnosed with sporadic NF-PanNETs and undergoing surgery between 2018 and 2021 were prospectively included in the research (DETECTYON; NCT03918759). Sensitivity, specificity, and positive and negative predictive values were used to evaluate the efficacy of preoperative imaging in detecting N+. About 100 patients with NF-PanNETs had pancreatic resection preceded by CE-CT, EUS, and 68Ga-DOTATOC PET. A total of 42 patients (42%) were found to have lymph node metastases. In terms of imaging methods, the sensitivity, specificity, positive predictive value, and negative predictive value of CE-CT were 26%, 95%, 79%, and 64%; those of EUS were 19%, 98%, 89%, 63%; and those of 68Ga-DOTATOC PET were 12%, 95%, 63%, 60%. There were 2 independent predictors of N+ at pathology: radiologic tumor size of more than 4 cm and the presence of radiologic N+ at 1 imaging. More positive LNs were found to be linked to the N+ at 1 imaging technique than to the negative imaging approach (4 vs. 2) (P=0.012). Although they are highly specific, CE-CT, EUS, and 68Ga-DOTATOC PET have low sensitivity for determining nodal status in NF-PanNETs.
