Magnetic Resonance Imaging versus Computed Tomography for Biliary Tract Intraductal Papillary Mucinous Neoplasm (BT-IPMN): A Diagnostic Performance Analysis

Background: In most cases, biliary tract intraductal papillary mucinous neoplasm (BT-IPMN) is depicted by pathological features rather than on imaging modalities, but fine-needle aspiration cytology cannot provide complete information on tumor(s). Computed tomography (CT) has the advantage of high spatial resolution and multiplanar capabilities, while magnetic resonance imaging (MRI) has greater contrast resolution than CT. The purpose of this study was to compare the diagnostic performance of CT vs. MRI for the diagnosis of BT-IPMN using surgical pathology as the reference standard. Material and methods: Data from CT, MRI, and surgical pathology of 210 patients with complaints of abdominal discomfort, vomiting, and/or jaundice for at least 6 months were included in the analysis. Intra-observer agreements for diagnosis of neoplasm was evaluated by kappa statistics. Results: CT and MRI respectively detected 171 and 33 patients with BT-IPMN, 6 and 176 with biliary intraductal tubulopapillary neoplasms (BT-ITPN), and 28 and 6 with inconclusive results. Surgical pathology reported 179 patients with BT-IPMN and 25 patients with BT-ITPN. CT and MRI both had the same accuracy (97.14%) for BT-IPMN. The sensitivities for diagnosis of BT-IPMN were 87.75%, 83.81%, and 81.43% for the surgical pathology, MRI, and CT, respectively. Intra-observer agreements for diagnosis of neoplasm were substantial (k=0.79), perfect (k=0.81), and perfect (k=0.85) for CT, MRI, and surgical pathology, respectively. Conclusions: MRI appears to be a more accurate and reliable method than CT for depicting BT-IPMN.