Diagnostic value of CEUS LI-RADS and serum tumor markers for combined hepatocellular-cholangiocarcinoma

Purpose:To analyze the contrast-enhanced ultrasound (CEUS) manifestations of combined hepatocellularcholangiocarcinoma (CHC) and to investigate the diagnostic value of the 2017 version of the CEUS Liver Imaging Reporting and Data System (LI-RADS) and serum tumor markers in CHC. Methods:A total of 66 pathologically confirmed CHC nodules were retrospectively analyzed. We summarized the CEUS manifestations of CHC and analyzed the relationship between serum tumor markers and the enhancement pattern of CHC. We also classified CHC according to CEUS LI-RADS criteria. The Kappa test was used to assess the interreader agreement of CEUS LI-RADS between radiologists. Result:According to the results, 52 of 62 (83.9%) patients had elevated alpha-fetoprotein (AFP), 19 of 61 (31.1%) had elevated carbohydrate antigen 199 (CA 199), and 13 of 61 (21.3%) had both elevated AFP and CA 199. Of the 66 CHC nodules, 64 (97.0%) were identified as malignant lesions by CEUS, 13 (19.7%) showed a hepatocellular carcinoma-like enhancement pattern, and 21 (31.8%) showed a cholangiocarcinoma-like enhancement pattern. For the CEUS LI-RADS categories, 39 of 53 (73.6%) CHC nodules were classified as LR-M, 12 (22.6%) were classified as LR-5, and 2 (3.8%) were classified as LR-4. The interreader agreement for the LI-RADS categories was 0.60. Conclusions:Although CHC lacks specific CEUS features, CEUS LI-RADS and serum tumor markers can be useful tools for reducing the misdiagnosis of CHC. In addition, due to the relative complexity of the CEUS features involved in CHC, it is necessary for beginning radiologists to learn more about CEUS features.