Extrahepatic Cholangiocarcinoma Missed And Misdiagnosed At MSCT:Features And Countermeasures

Part one Extrahepatic cholangiocarcinoma missed and misdiagnosed at MSCT: Features and countermeasuresObjective: To investigate the features of missed and misdiagnosed extrahepatic cholangiocarcinoma(EHCC)by Multi-slice spiral computed tomography(MSCT)retrospectively,and analyze the causes of missing and misdiagnosis of EHCC.Method:77 cases with EHCC confirmed by pathology were enrolled from September 2015 to December 2018 in the second hospital of Hebei Medical University.All patients received MSCT plain scan and enhanced scan of the upper abdomen before surgery.Observe the morphology,location,length,degree of enhancement of the lesion,and the degree of biliary obstruction.Result:Surgical procedures such as biliary drainage were performed before the MSCT examination in 5 cases,which affected the observation of lesions.Therefore,these 5 cases were excluded in the subsequent study.Among the remaining 72 patients,22 patients failed to be diagnosed with EHCC,and the missing and misdiagnosis rate was 30.6%(22/72).There was a statistically significant difference in the missing and misdiagnosis rate between infiltrating EHCC and mass-forming EHCC(56.3%,10.0%).There was no significant difference in the overall misdiagnosis rate between hilar EHCC and common bile duct EHCC(23.3%,35.7%).In the mass-forming EHCC group,there was no significant difference in the misdiagnosis rate between hilar EHCC and common bile duct EHCC(13.6%,5.9%).In the infiltrating EHCC group,there was no significant difference in the misdiagnosis rate between hilar EHCC and common bile duct EHCC(50.0%?58.3%).In the mass-forming EHCC group,there was no significant difference in the misdiagnosis rate of tumors < 1.5cm,1.5-2.0cm,and > 2.0cm(16.7%,6.7%,11.1%).In the infiltrating EHCC group,the missed diagnosis rate of tumors < 1.5cm,1.5-2.0cm,and > 2.0cm(66.7%,40.0%,60.0%)was not statistically significant.In the portal vein phase,there was no statistically significant difference in the rate of missed diagnosis in patients with moderate and significantly enhanced lesions(36.7%,26.2%).In the delayed phase,there was no significant difference in the misdiagnosis rate(33.3%,24.1%,35.1%)among patients with mild,moderate and significantly enhanced lesions.Among the 42 cases of common bile duct EHCC,there was no statistically significant difference in the missing and misdiagnosis rate between patients without common bile duct dilation,mild,moderate and severe common bile duct dilation(27.2%,62.5%,50.0%,20.0%).72 cases were associated with intrahepatic bile duct expansion.There was no statistically significant difference in the missing and misdiagnosis rate between the patients with mild,moderate,severe expansion of primary intrahepatic bile duct(33.3%,47.1%,25.0%).The difference of the missing and misdiagnosis rate between the patients with mild,moderate,severe expansion of secondary intrahepatic bile duct(57.1%,39.3%,15.6%)was statistically significant.Conclusion:The missing and misdiagnosis of EHCC was related to tumor morphology and the degree of secondary intrahepatic bile duct.The missing and misdiagnosis rate of infiltrating EHCC is higher than that of mass-forming EHCC.The more obvious the secondary bile duct branch dilation,the lower the rate of missed diagnosis.The misdiagnosis of EHCC has little relation with tumor size(length),location and degree of enhancement.Surgical operations such as biliary drainage before MSCT examination significantly affect the diagnostic rate of EHCC.The application of MSCT multi-plane reformation and curved planar reformation can improve the detection rate of EHCC.Part two Evaluate the diagnositic value of secondary intrahepatic bile duct and serum CA19-9 by ROC curveObjective: To explore the value of secondary bile duct branch diameter and serum CA19-9 level in the diagnosis of EHCC with the use of ROC curve.Method:72 patients with extrahepatic cholangiocarcinoma confirmed by postoperative pathology in the second hospital of Hebei Medical University from September 2015 to December 2018(defined as EHCC group)were included.Meanwhile,36 patients with benign biliary tract obstruction of extrahepatic bile duct confirmed by ERCP or clinical follow-up during the same period were selected(defined as benign lesion group).All patients received MSCT plain scan and enhanced scan of upper abdomen before operation or ERCP,and serum CA19-9 level was determined.The ROC curve was used to analyze the diagnostic efficacy of the diameter of secondary bile duct branches,serum CA19-9 level and the two combined in diagnosing EHCC.And determine the critical value of secondary bile duct diameter and serum CA19-9 in diagnosing EHCC.Result:The median diameter of secondary bile duct branches in EHCC group and benign lesion group were 8.0(7.0-10.0)mm and 5.0(4.0-7.0)mm,respectively,with statistically significant differences between the two groups.The medians of serum CA19-9 in EHCC group and benign lesion group were 119.15(47.58-213.98)U/ml and 29.59(18.20-128.15)U/ml,respectively.The differences between the two groups were statistically significant.The area under the ROC curve of secondary bile duct branch diameter for EHCC diagnosis was 0.797,with a critical value of 6.5mm,a sensitivity of 77.8%,and a specificity of 72.2%.The area under the ROC curve of serum CA19-9 for diagnosing EHCC was 0.713,with a critical value of 39.73U/ml,a sensitivity of 80.6% and a specificity of 63.9%.The area under the ROC curve of the combined application was 0.814,and the sensitivity and specificity were 84.7% and 72.2%,respectively.Conclusion:Secondary bile duct branch diameter and serum CA19-9 level have certain diagnostic efficacy for EHCC.Combined application of the two methods can help improve the accuracy of MSCT for EHCC.