Comparison of the accuracy of AASLD and LI-RADS criteria for the non-invasive diagnosis of HCC smaller than 3 cm

Background & aims: Non-invasive imaging is crucial for the early diagnosis and successful treatment of hepatocellular carcinoma (HCC). Terminology and criteria for interpreting and reporting imaging results must be standardized to optimize diagnosis. The aim of this study was to prospectively compare the diagnostic accuracy of the American Association for the Study of Liver Diseases (AASLD) and the 2014 version of Liver Imaging Reporting and Data System (LI-RADS®) criteria for the non-invasive diagnosis of small HCC, and to evaluate the diagnostic value of ancillary features used in the LI-RADS criteria.

Methods: Between April 2009 and April 2012, patients with cirrhosis and one to three 10-30 mm nodules were enrolled and underwent computed tomography (CT) and magnetic resonance (MR) imaging. The diagnostic accuracy of both the AASLD and the LI-RADS criteria were determined based on their sensitivity, specificity, positive (PPV) and negative predictive values (NPV).

Results: A total of 595 nodules were included (559 [341 HCC, 61%] with MR imaging and 529 [332 HCC, 63%] with CT). Overall, no (0%) LR-1 and LR-2, 44 (33%) and 47 (41%) LR-3, 50 (53%) and 54 (55%) LR-4, 244 (94%) and 222 (91%) LR-5 and 4 (67%) and 9 (82%) LR-5V were HCC on MR imaging and CT, respectively. The sensitivity, specificity, PPV/NPV of the AASLD score was 72.5%, 87.6%, 90.2%, and 66.9% for MR imaging, and 71.4%, 77.7%, 84.3%, 61.7% for CT, respectively. For the combination of LR-5V and LR-5 nodules these measures were 72.5%, 89.9%, 91.9% and 67.5% on MRI and 66.9%, 88.3%, 90.9% and 63.3% on CT, respectively. For the combination of LR-5V, LR-5 and LR-4 nodules they were 87.1%, 69.1%, 81.6% and 77.3% on MRI and 85.8%, 66%, 81% on 73.5% on CT, respectively.

Conclusion: The 2014 version of the LI-RADS is no more accurate than the AASLD score for the non-invasive diagnosis of small HCC in high-risk patients, but it provides important and complementary information on the probability of having HCC in high-risk patients, allowing for possible changes in the management of these patients.

Lay summary: The 2014 version of Liver Imaging Reporting and Data System criteria does not outperform the American Association for the Study of Liver Diseases criteria for the non-invasive diagnosis of hepatocellular carcinoma (HCC) smaller than 3 cm. Liver Imaging Reporting and Data System offers a nodule-based evaluation of the risk of HCC, allowing possible changes in management in these patients. The added value of ancillary features appears limited for the non-invasive diagnosis of small HCC.