This study aims to identify the computed tomography (CT) features that may differentiate nonfunctioning pancreatic neuroendocrine tumors (NF-PanNETs) with lymph node (LN) metastasis from NF-PanNETs without lymph node metastasis.Methods
We retrospectively analyzed 166 NF-PanNETs in 166 patients who had undergone surgical resection (median age, 53). Two radiologists evaluated the qualitative and quantitative CT findings. Through univariate and multivariate logistic regression analyses, we determined independent significant findings for differentiating NF-PanNETs with LN metastasis from NF-PanNETs without LN metastasis. Recurrence-free survival (RFS) and overall survival (OS) were compared between the 2 groups using Kaplan-Meier analysis and log-rank testing.Results
Of the 166 NF-PanNETs, 24 (14.5%) tumors demonstrated LN metastasis. Three CT findings, radiologic LN enlargement (adjusted odds ratio [OR], 11.76; P = 0.001), liver metastasis (OR, 10.31; P = 0.027), and portal enhancement ratio of <1.238 (OR, 3.58; P = 0.033), were independently significant for differentiating NF-PanNETs with LN metastasis from NF-PanNETs without LN metastasis. Tumor size greater than 2 cm also showed a statistically marginal significance (OR, 8.47; P = 0.050). The median RFS and OS in NF-PanNETs with LN metastasis were significantly shorter than NF-PanNETs without LN metastasis (23.7 months vs 33.2 months, P < 0.001; 33.7 months vs 54.8 months, P < 0.001).Conclusions
Four CT findings can be useful to differentiate NF-PanNETs with LN metastasis and NF-PanNETs without LN metastasis.