Comparison of LI-RADS 2018 and KLCA-NCC 2018 for noninvasive diagnosis of hepatocellular carcinoma using magnetic resonance imaging

Background/Aims: This study aimed to compare the diagnostic performances of Liver Imaging Reporting and Data System (LI-RADS) 2018 and Korean Liver Cancer Association-National Cancer Center (KLCA-NCC) 2018 criteria on magnetic resonance imaging (MRI) for the noninvasive diagnosis of hepatocellular carcinoma (HCC) in high-risk patients.Methods: This retrospective study included 273 treatment-naïve patients (71 patients with extracellular contrast agent [ECA]-MRI and 202 patients with hepatobiliary agent [HBA]-MRI; 352 lesions including 263 HCCs) with high risk of HCC who underwent contrast-enhanced MRI between 2016 and 2017. Two readers evaluated all lesions according to the criteria of LI-RADS 2018 and KLCA-NCC 2018. The per-lesion diagnostic performances were compared using the generalized estimating equation method.Results: On ECA-MRI, the sensitivity and specificity of LI-RADS 2018 and KLCA-NCC 2018 were not significantly different (LR-5 vs. definite HCC: 75.8% vs. 69.4%, <i>P</i>=0.095 and 95.8% vs. 95.8%, <i>P</i>>0.999; LR-5/4 vs. definite/probable HCC: 87.1% vs.83.9%, P=0.313 and 87.5% vs. 91.7%, <i>P</i>=0.307). On HBA-MRI, definite HCC of KLCA-NCC 2018 showed significantly higher sensitivity (79.1% vs. 68.2%, <i>P</i><0.001) than LR-5 of LI-RADS 2018 without a significant difference in specificity (93.9% vs. 95.4%, <i>P</i>=0.314). Definite/probable HCC of KLCA-NCC 2018 had higher specificity (92.3% vs. 80.0%, <i>P</i>=0.003) than LR-5/4 of LI-RADS 2018. The sensitivity was lower for definite/probable HCC than for LR-5/4 without statistical significance (85.6% vs. 88.1%, <i>P</i>=0.057).Conclusions: On ECA-MRI, LI-RADS 2018 and KLCA-NCC 2018 showed comparable diagnostic performances. On HBA-MRI, definite HCC of KLCA-NCC 2018 provided better sensitivity than LR-5 category of LI-RADS 2018 without compromising the specificity, while definite/probable HCC of KLCA-NCC 2018 revealed higher specificity than LR-5/4 of LI-RADS 2018 for diagnosing HCC.

The possibility of applying magnetic resonance imaging with hepatospecific contrast agent.

Nowadays, it is difficult to overestimate the role of cross-sectional imaging in the diagnosis of focal and diffuse liver diseases. In magnetic resonance imaging (MRI) there is a unique opportunity to use hepatospecific contrast agents compared with other visualization techniques. Gadoxetic acid is a hepatospecific magnetic resonance contrast agent which has the extracellular contrast agent properties and hepatotropic property. About half of the administered dose of gadoxetic acid enters into functioning hepatocytes through cell membrane transporters and then is excreted into the bile ducts and sinusoidal space. The obtained hepatobiliary phase provides information about the structural features of the focal liver lesions, improving their detection and differential diagnosis. In addition it allows to assess the anatomical and functional conditions of the hepatobiliary system. This article describes clinical applications of MRI with gadoxetic acid and its benefits, visualization principles of different focal liver lesions in hepatobiliary phase and features of the obtained images.