Published online Jul 21, 2022. doi: 10.3748/wjg.v28.i27.3488
Peer-review started: December 17, 2021
First decision: January 27, 2022
Revised: February 10, 2022
Accepted: June 16, 2022
Article in press: June 16, 2022
Published online: July 21, 2022
Patients affected by liver cirrhosis are at high risk of developing hepatocellular carcinoma (HCC) and other malignancies such us intrahepatic cholangiocellular carcinoma (ICC). Diagnostic tools to characterize new-onset nodules in cirrhosis include contrast-enhanced ultrasound (CEUS), but this technique has been challenged for the possibility of misdiagnosing HCC and ICC.
The CEUS Liver Imaging Reporting and Data System (CEUS LI-RADS) aims to refine CEUS interpretation in order to improve the differentiation of HCC from other malignancies. Nevertheless, its effectiveness in real-life context has not yet been well established.
To test the accuracy of CEUS LI-RADS in correctly diagnosing HCC and ICC in cirrhosis with LR-5 and LR-M class, respectively, to evaluate the performance of LR-4 and 5 merging class in the diagnosis of HCC, and to investigate the rate of malignancies in different LR-3 patterns.
This study consecutively collected 511 nodules in 269 cirrhotic patients from December 2008 to January 2020. A CEUS LI-RADS class was retrospectively attributed to each nodule based on review of CEUS examination. Common diagnostic accuracy indexes were assessed for the following associations: CEUS LR-5 and HCC; CEUS LR-4 and 5 merged class and HCC; CEUS LR-M and ICC; CEUS LR-3 and malignancy. The diagnostic standard was either biopsy or computed tomography/magnetic resonance imaging. The frequency of malignant lesions in CEUS LR-3 subgroups with different CEUS patterns was also determined.
CEUS LR-5 showed a 97.7% specificity for HCC with a low sensitivity (67.6%), while the CEUS LR-4 and 5 merged class showed a 93.9% sensitivity and 94.3% specificity for HCC. CEUS LR-M predicted ICC with a 91.3% sensitivity and 96.7% specificity. CEUS LR-3 predominantly included benign lesions (28.8% of malignancies) but was heterogeneous as the hypo-hypo pattern showed a higher rate of malignant lesions (73.3%) than the iso-iso pattern (2.6%).
HCC diagnosis could benefit from the merging of CEUS LI-RADS classes 4 and 5. In addition, splitting LR-3 class could be advantageous to differentiate iso-iso nodules from other patterns with a higher risk of malignancy.
Further prospective multicentric studies are necessary to confirm and extend our findings to the general population.