ObjectiveTo explore value of CT imaging features in differentiating pathological grades of pancreatic neuroendocrine neoplasms (pNENs). MethodsThe patients with pNENs admitted to the Sichuan Provincial People’s Hospital from October 2017 to December 2023 were retrospectively collected. The enrolled patients were assigned into a low-grade (G1+G2) pNENs and high-grade (G3+neuroendocrine carcinoma) pNENs. Then, the differences in gender, age, presence of neuroendocrine symptoms, tumor location, tumor diameter, clarity of the tumor boundary, cystic change, capsule, dilation of the biliary and pancreatic ducts, pancreatic parenchymal atrophy, vascular invasion, liver metastasis, lymph node metastasis, tumor enhancement pattern, Ct values in each phase, and the ratio of Ct value of the tumor to that of the normal pancreas (T/N value) between the low-grade pNENs and high-grade pNENs were compared. Subsequently, the multivariate logistic regression analysis was used to screen the CT imaging features with statistical significance and the receiver operating characteristic (ROC) curve was use to differentiate high-grade from low-grade pNENs. ResultsA total of 47 pNENs patients were enrolled, including 36 low-grade and 11 high-grade cases. Compared with the low-grade pNENs, the patients with high-grade pNENs had higher proportions of pancreaticobiliary duct dilation (χ2=9.124, P=0.003) and vascular invasion (χ2=10.967, P=0.001), more mild enhancement (χ2=9.192, P=0.010), larger tumor diameter (Z=–2.378, P=0.017), and lower Ct values and T/N ratios in the arterial and venous phases (P=0.001, P=0.032, P=0.006, P=0.018). The multivariate logistic regression analysis showed that the pancreaticobiliary duct dilation, vascular invasion, and decreased Ct value in the arterial phase were the predictive factors for the high-grade pNENs. The areas under the ROC curves of these three indicators for distinguishing low-grade from high-grade pNENs were 0.760, 0.749, and 0.843, respectively, the Ct value in the arterial phase had the strongest discriminatory ability, and its cutoff value was 78 HU. ConclusionsThe results of this study suggest that pancreatic ductal dilation, vascular invasion, and Ct value in arterial phase play important roles in differentiating high-grade pNENs from low-grade pNENs. Ct value in arterial phase has the greatest diagnostic efficiency.