Solid pseudopapillary neoplasms of the pancreas (SPNs): Diagnostic accuracy of CT and CT imaging features

Purpose: To summarize the abdominal computed tomography (CT) imaging and clinicopathological data of patients with SPNs of the pancreas and analyze the accuracy of preoperative CT diagnosis and features. Materials and Methods: Between June 2006 and June 2023, CT images of 120 histopathologically proven SPNs in the pancreas were retrospectively reviewed. The 15 features of age, sex, and CT-determined features were included in multiple stepwise regression analysis. The correlation between features and SPNs was evaluated, including odds ratio (OR) and 95% confidence interval (CI). Results: Of the 120 patients, the diagnostic accuracy of CT was 43.3%. The baseline CT results of patients with a correct diagnosis and misdiagnosis showed that there were significant differences in sex (P=0.043), age (P=0.004), boundary (P=0.037) and encapsulation (P=0.002) between the two groups. The preoperative imaging diagnostic accuracy was significantly greater in females than in males (47.9% vs. 25.0%, P=0.043). There was no significant difference in immunohistochemical indices between the two groups. The results of univariate analysis revealed significant differences in sex (P=0.048), age (P=0.014), tumor length (P=0.023), tumor boundaries (P=0.039) and capsule type (P=0.003). The results of multivariate analysis showed that encapsulation was closely related to the diagnostic accuracy of CT (P=0.04). Conclusions: The accuracy of CT in the diagnosis of SPNs is low, but the length‒diameter ratio of the tumor approaching 1.0, encapsulation and clear boundary are important CT-determined features. The capsule is an independent CT predictor in the diagnosis of SPNs.