CT Diagnosis Of Hilar Cholangiocarcinoma And Preoperative Evaluation Of Vascular Invasion

Part I CT imaging features and differential diagnosis of perihilar cholangiocarcinoma with different gross morphologiesObjective: Discuss CT imaging features and differential diagnosis based on different gross morphologies of perihilar cholangiocarcinoma.Methods: 83 cases of perihilar diseases confirmed by histopathology were retrospectively analyzed by two radiologists.Compared CT imaging features and enhancement patterns according to different gross morphologies of perihilar cholangiocarcinoma and perihilar benign diseases to find whether there was a significant difference.Results: There are 15 cases of intraductal growing diseases,and the diameter of perihilar cholangiocarcinoma larger than perihilar benign diseases significantly.All of them are wash-in and wash-out pattern of enhancement.There are 38 cases of periductal infiltrating diseases.Perihilar cholangiocarcinoma has significantly shorter longitudinal length,biliary stricture,bile duct thickness and soft rattan distant biliary dilatation.Most of them are wash-in and wash-out pattern of enhancement.The diseases of mass-forming are mostly perihilar cholangiocarcinoma,and the enhancement pattern is persistent enhancement and progressive enhancement.Conclusion: Different gross morphologies of perihilar cholangiocarcinoma have different CT features and can be identified with benign diseases.Part II Modification and Establishment of CT Criteria in Preoperative Assessment of Portal Venous Invasion by Hilar CholangiocarcinomaBackground: To compare the diagnostic performance of CT criteria and to establish a new model in evaluating portal venous invasion by hilar cholangiocarcinoma.Methods: CT images of 67 patients with hilar cholangiocarcinoma were retrospectively reviewed.Modified Loyer's,Lu's and Li's standard introduced from pancreatic cancer were used to evaluate portal venous invasion with the reference of intraoperative findings and/or postoperative pathological diagnosis.A new model was constructed with modified Lu's standard and contact length between portal vein and tumor.Results: The modified Loyer's standard,modified Lu's standard and Li's standard showed a sensitivity of 86.7%,83.3%,70.0%,a specificity of 89.4%,95.7%,95.7% and an accuracy of 88.6%,92.0%,88.1%,respectively.CT criteria performed better in evaluating left branch.The new model performed significantly better than any CT criterion or contact length,with a sensitivity of 95.0%,a specificity of 96.5% and an accuracy of 96.0%.Conclusions: Modified Lu's standard performed best in evaluating portal venous invasion by hilar cholangiocarcinoma among three CT criteria.The left branch invasion could be evaluated by CT criteria better than the right branch and the trunk of portal vein.The new mode significantly improved the diagnostic performance of portal venous invasion by hilar cholangiocarcinoma.Part III Modification and comparison of CT criteria in preoperative assessment of hepatic arterial invasion by hilar cholangiocarcinomaObjective: To compare the diagnostic performance of three CT criteria and two signs in evaluating hepatic arterial invasion by hilar cholangiocarcinoma.Methods: CT images of 61 patients with hilar cholangiocarcinoma were retrospectively reviewed.Modified Loyer's,Lu's and Li's standards were used to evaluate hepatic arterial invasion by hilar cholangiocarcinoma with the reference of intraoperative findings and/or postoperative pathological diagnosis.Arterial circuity and contact length were also evaluated.Results: The Loyer's,Lu's and Li's standards showed a sensitivity of 88.9%,87.0%,72.2%,a specificity of 93.8%,93.8%,94.6%,and an accuracy of 92.4%,91.8%,88.0% in evaluating hepatic arterial invasion by hilar cholangiocarcinoma.The Loyer's and Lu's standards performed better than the Li's standard(P = 0.049).CT criteria performed best in evaluating proper hepatic arterial invasion compared with the left and right hepatic artery.With a cut-off contact length of 10.9 mm,3 false negative cases could be avoided.Conclusions: The Loyer's and Lu's standards performed best in evaluating hepatic arterial invasion by hilar cholangiocarcinoma on preoperative CT images,especially in assessing the proper hepatic artery.Combination of the contact length and the Loyer's standard could improve the diagnostic performance.