Impact of the Liver Imaging Reporting and Data System on Research Studies of Diagnosing Hepatocellular Carcinoma Using MRI

Abstract

Objective Since its introduction in 2011, the CT/MRI diagnostic Liver Imaging Reporting and Data System (LI-RADS) has been updated in 2014, 2017, and 2018. We evaluated the impact of CT/MRI diagnostic LI-RADS on liver MRI research methodology for the diagnosis of hepatocellular carcinoma (HCC). Materials and Methods The MEDLINE, EMBASE, and Cochrane databases were searched for original articles reporting the diagnostic performance of liver MRI for HCC between 2011 and 2019. The MRI techniques, image analysis methods, and diagnostic criteria for HCC used in each study were investigated. The studies were classified into three groups according to the year of publication (2011–2013, 2014–2016, and 2017–2019). We compared the percentage of studies adopting MRI techniques recommended by LI-RADS, image analysis methods in accordance with the lexicon defined in LI-RADS, and diagnostic criteria endorsed by LI-RADS. We compared the pooled sensitivity and specificity between studies that used the LI-RADS and those that did not. Results This systematic review included 179 studies. The percentages of studies using imaging techniques recommended by LI-RADS were 77.8% for 2011–2013, 85.7% for 2014–2016, and 84.2% for 2017–2019, with no significant difference ( p = 0.951). After the introduction of LI-RADS, the percentages of studies following the LI-RADS lexicon were 0.0%, 18.4%, and 56.6% in the respective periods ( p < 0.001), while the percentages of studies using the LI-RADS diagnostic imaging criteria were 0.0%, 22.9%, and 60.7%, respectively ( p < 0.001). Studies that did not use the LI-RADS and those that used the LI-RADS version 2018 showed no significant difference in sensitivity and specificity (86.3% vs. 77.7%, p = 0.102 and 91.4% vs. 89.9%, p = 0.770, respectively), with some difference in heterogeneity (I 2 = 94.3% vs. 86.7% in sensitivity and I 2 = 86.6% vs. 53.2% in specificity). Conclusion LI-RADS imparted significant changes in the image analysis methods and diagnostic criteria used in liver MRI research for the diagnosis of HCC.

Standardizing liver imaging reporting and interpretation: LI-RADS and beyond

“…For example, almost 70% of scientific studies performed between 2011 and 2013 used nonstandardized imaging diagnostic criteria created for the purpose of the study (ie, study-specific imaging diagnostic criteria) for HCC, and 80% of these scientific studies used study-specific definitions for major features of HCC. 17 This between-study variability in the definitions for the appearance of HCC in the arterial phase (AP) led to inconsistencies regarding whether an observation enhancing in the AP equally to the background parenchyma could qualify as HCC. 1 Similarly, scientific studies had variable definitions of washout, some defining washout as hypoenhancement in the portal venous or delayed phases, without specifying lesional appearance in the AP, while some requiring lesional hyperenhancement in the AP in addition to hypoenhancement in portal venous or delayed phases.…”

“…In the period of 2017–2019, 57% of scientific studies investigating MRI for HCC diagnosis used LI-RADS lexicon and 61% used LI-RADS diagnostic criteria for HCC. 17 As a result, the use of study-specific definitions for major features and study-specific imaging diagnostic criteria for HCC has declined in 2017–2019 period to 25% and 12%, respectively. 17 Increased consistency between the studies allowed for easier and clearer data synthesis: to date, Pubmed lists over 650 publications on LI-RADS, of which 41 performed systematic review and/or meta-analysis, focusing on diagnostic performance of categories and imaging features, inter-reader reliability, and intermodality comparison of CT/MRI Diagnostic LI-RADS, CEUS LI-RADS, and LI-RADS TRA.…”

“… 17 As a result, the use of study-specific definitions for major features and study-specific imaging diagnostic criteria for HCC has declined in 2017–2019 period to 25% and 12%, respectively. 17 Increased consistency between the studies allowed for easier and clearer data synthesis: to date, Pubmed lists over 650 publications on LI-RADS, of which 41 performed systematic review and/or meta-analysis, focusing on diagnostic performance of categories and imaging features, inter-reader reliability, and intermodality comparison of CT/MRI Diagnostic LI-RADS, CEUS LI-RADS, and LI-RADS TRA. In large part due to this scientific rigor, algorithms and management recommendations of US and CT/MRI Diagnostic LI-RADS were integrated into the American Association for Study of Liver Diseases (AASLD) practice guidance since 2018.…”