DALLAS – For more than a decade, the Liver Imaging Reporting and Data System (LI-RADS) has been used to standardize the interpretation and reporting of liver lesions in patients at high risk for hepatocellular carcinoma (HCC).

Yet, predicting what happens with indeterminate liver nodules (ILNs), which are frequently encountered on diagnostic imaging after positive HCC surveillance results, remains difficult, according to researchers from the University of Texas Southwestern in Dallas and colleagues, including the Michael E. DeBakey VAMC in Houston.

For the report published in the American Journal of Gastroenterology, the investigative team conducted a multicenter retrospective cohort study among patients with one or more newly detected LI-RADS 3 (LR-3) lesion larger than 1 cm or LI-RADS 4 (LR-4) lesion of any size (per LI-RADS v2018) between January 2018 and December 2019. 1

Of 307 patients with ILNs, 208 had LR-3 lesions, 83 had LR-4 lesions, and 16 had both LR-3 and LR-4 lesions, the authors noted. Patients were followed with repeat imaging at each site per institutional standard of care.

Results indicated that HCC incidence rates for patients with LR-3 and LR-4 lesions were 110 (95% CI 70-150) and 420 (95% CI 310-560) per 1,000 person-year, respectively.

The researchers explained that, in multivariable analysis, incident HCC among patients with LR-3 lesions was associated with older age, thrombocytopenia (platelet count ≤150 ×10 9 /L), and elevated serum alpha-fetoprotein levels. Among those with LR-4 lesions, however, incident HCC was associated with a maximum lesion diameter >1 cm.

“Although most patients had follow-up computed tomography or magnetic resonance imaging, 13.7% had no follow-up imaging and another 14.3% had follow-up ultrasound only,” the researchers advised, adding, “ILNs have a high but variable risk of HCC, with 4-fold higher risk in patients with LR-4 lesions than those with LR-3 lesions, highlighting a need for accurate risk stratification tools and close follow-up in this population.”

Recently, an international study published in Abdominal Radiology looked at the value of Contrast-Enhanced Ultrasound (CEUS) and whether that is a clinically useful additional step when Computed tomography (CT) or Magnetic resonance imaging (MRI) results are inconclusive.

“Hepatocellular carcinoma (HCC) is a unique cancer allowing tumor diagnosis with identification of definitive patterns of enhancement on contrast-enhanced imaging, avoiding invasive biopsy. However, it is still unclear to what extent,” wrote the first authors from the University of California, San Diego and colleagues.

They described how a prospective international multicenter validation study for CEUS Liver Imaging Reporting and Data System (LI-RADS) was conducted between January 2018 and August 2021. It enrolled 646 patients at risk for HCC with focal liver lesions, and CEUS was performed using an intravenous ultrasound contrast agent within 4 weeks of CT/MRI.

Liver nodules were categorized based on LI-RADS (LR) criteria, according to the report, which added that histology or one-year follow-up CT/MRI imaging results were used as the reference standard. The researchers evaluated the diagnostic performance of CEUS for inconclusive CT/MRI scan in two scenarios for which the AASLD recommends repeat imaging or imaging follow-up: observations deemed non-characterizable (LR-NC) or with indeterminate probability of malignancy (LR-3).

The investigators advised that “75 observations on CT or MRI were categorized as LR-3 (n = 54) or LR-NC (n = 21) CEUS recategorization of such observations into a different LR category (namely, into one among LR-1, LR-2, LR-5, LR-M, or LR-TIV) resulted in management recommendation changes in 33.3% (25/75) and in all but one (96.0%, 24/25) observation, the new management recommendations were correct.”

The study concluded that CEUS LI-RADS “resulted in management recommendations change in a substantial number of liver observations with initial indeterminate CT/MRI characterization, identifying both non-malignant lesions and HCC, potentially accelerating the diagnostic process and alleviating the need for biopsy or follow-up imaging.”.

 

  1. Singal AG, Parikh ND, Shetty K, Han SH, Xie C, Ning J, Rinaudo JA, Arvind A, Lok AS, Kanwal F; Translational Liver Cancer Investigators. Natural History of Indeterminate Liver Nodules in Patients With Advanced Liver Disease: A Multicenter Retrospective Cohort Study. Am J Gastroenterol. 2024 May 29. doi: 10.14309/ajg.0000000000002827. Epub ahead of print. PMID: 38686922.
  2. Kono Y, Piscaglia F, Wilson SR, Medellin A, et. Al. CEUS LI-RADS Trial Group. Clinical impact of CEUS on non-characterizable observations and observations with intermediate probability of malignancy on CT/MRI in patients at risk for HCC. Abdom Radiol (NY). 2024 Jun 11. doi: 10.1007/s00261-024-04305-9. Epub ahead of print. PMID: 38860996.