Abstract: Objective The aim of this study was to evaluate the value of contrast-enhanced ultrasound (CEUS) and serum carbohydrate antigen (Ca19-9) levels in differential diagnosis of patients with intrahepatic cholangiocellular carcinoma (ICC) and hepatocellular carcinoma (HCC). Methods 48 patients with histopathological confirmed ICC and 78 patients with histopathological confirmed HCC were enrolled in this study, and all underwent CEUS and serum CA19-9 levels were detected. A binary Logistic regression model was established for the differential diagnosis of ICC and HCC. Results 45.8% ICC patients had peripheral rim enhancement of tumors at CEUS, significantly higher than 2.6% in HCC patients (P <0.05); the marked washout was found in 58.3% of ICC patients,However, 94.9% HCC patients were weak or not washout (P <0.05); the washout time in ICC group was(54.6±10.2)s, significantly earlier than (76.1±25.1)s in HCC group (P <0.05); 72.9% ICC patients had increased serum CA19-9 levels, significantly higher than 19.2% in HCC group (P<0.05); a binary Logistic diagnostic model equation was established: e.g. Logit(P)=-4.030+2.640×enhancement mode +2.486×washout time +2.579×washout degree +2.731×CA19-9 (u/ml), and the AUC was 0.943, with the sensitivity and specificity of 79.2% and 93.6% (P<0.05) in diagnosing ICC by this equation. Conclusion Compared with the diagnostic effect of a single indicator, logistic regression analysis based multi-indicator combined differential diagnosis of ICC and HCC has higher diagnostic value.

Key words: Intrahepatic cholangiocarcinoma, Hepatocellular carcinoma, Contrast-enhanced ultrasound, Carbohydrate antigen 19-9, Diagnosis