Diagnostic Performance of CT/MRI Liver Imaging Reporting and Data System v2017 for Hepatocellular Carcinoma: A Systematic Review and Meta‐Analysis

Abstract

Background & Aims:The liver Imaging Reporting and Data System (LI-RADS) is a comprehensive system for standardizing liver imaging in patients at high risk for hepatocellular carcinoma (HCC). We performed a meta-analysis to determine the diagnostic performance of the LR-5 category for HCC and the pooled proportions of HCCs in each LI-RADS category using CT/MRI LI-RADS v2017. Methods:We searched multiple databases for original studies reporting on the diagnostic accuracy of CT/MRI LI-RADS v2017. Random-effects models were used to determine the summary estimates of the diagnostic performance of the LR-5 category and the pooled proportions of HCCs for each LI-RADS category. Risk of bias and concerns regarding applicability were evaluated with the Quality Assessment of Diagnostic Accuracy Studies-2 tool.Results: Fourteen studies (3 prospective studies and 11 retrospective studies) were included in the final analysis, consisting of 2056 patients, 2589 observations, and 1693 HCCs. The pooled per-observation sensitivity was 67% (95% confidence interval [CI], 62%-72%) with specificity of 92% (95% CI, 88%-95%) in the LR-5 category of CT/MRI LI-RADS v2017 for diagnosing HCC. The pooled proportions of HCCs were 0% (95% CI, 0%-0%) for LR-1, 4% (95% CI, 0%-8%) for LR-2, 34% (95% CI, 23%-44%) for LR-3, 67% (95% CI, 53%-81%) for LR-4, and 92% (95% CI, 87%-96%) for LR-5.The proportions of HCCs were significantly different among LI-RADS categories 1-5 (P = .034). Conclusions:The LR-5 category of CT/MRI LI-RADS v2017 shows moderate sensitivity and high specificity for diagnosing HCC. Higher LI-RADS categories contained higher proportions of HCCs. K E Y W O R D S computed tomography, diagnosis, liver neoplasms, magnetic resonance imaging, sensitivity and specificity | 1489 LEE Et aL.

Contrast‐enhanced ultrasound liver imaging reporting and data system for diagnosing hepatocellular carcinoma: A meta‐analysis

“…The CEUS LR‐2 (probably benign) category indicated a high probability, though not 100% certainty, that an observation is benign, with the pooled proportion of HCC being 2%, which reflects the original concept and definition of the LI‐RADS. This finding is also in agreement with the results of a recent systematic review on CT/MRI LI‐RADS version 2017, which reported that the pooled percentage of HCCs for LR‐2 was 4% 21 . We also found that the pooled proportions of HCCs gradually increased from CEUS LR‐3 to CEUS LR‐5 (CEUS LR‐3, 26%; CEUS LR‐4, 77%; and CEUS LR‐5, 97%).…”

“…HCCs were not reported in CEUS LR‐1, a category that includes focal hepatic lesions that are definitely benign, including cysts, classic hemangiomas, and lesions showing fat deposition or fat sparing. This finding is in agreement with that of the previous systematic reviews on the CT/MRI LI‐RADS 21,23 . The CEUS LR‐2 (probably benign) category indicated a high probability, though not 100% certainty, that an observation is benign, with the pooled proportion of HCC being 2%, which reflects the original concept and definition of the LI‐RADS.…”

“…The pooled sensitivity for diagnosing HCC was 69% for the CEUS LR‐5 category. Both these values were similar to those reported in a previous meta‐analysis (specificity 92% and sensitivity 67%) using CT/MRI LI‐RADS version 2017 21 . Although all imaging modalities are complementary, and several factors affect the choice of modalities, the diagnostic performances of the different imaging modalities that use the LI‐RADS for HCC evaluation may be compared in research studies in the future.…”

“…Significant difference in sensitivity between Asian and non‐Asian countries is likely to be influenced by these technical factors of CEUS, unlike CT or MRI. The specificity of the CEUS LR‐5 category was significantly higher for studies using pathology and composite imaging or clinical follow‐up as a reference standard than for studies using only pathology; this finding is similar to that of a meta‐analysis using CT/MRI LI‐RADS version 2017 21 . In addition, both sensitivity and specificity were significantly higher for studies using CEUS LI‐RADS version 2017 than for those using CEUS LI‐RADS version 2016. International multicenter prospective studies are needed to validate the diagnostic performance of the CEUS LR‐5 category using the recently updated CEUS LI‐RADS version 2017 and a combination of pathology and composite clinical reference standard as a reference standard.…”

Risk factors for hepatocellular carcinoma recurrence after liver transplantation

“…LI-RADS is being increasingly adopted in clinical practice for patients at high risk of HCC, thereby enabling the categorization of observations from LR-1 (definitely benign) to LR-5 (definitely HCC) based on the level of suspicion for HCC. However, a recent meta-analysis [25] derived from 14 studies showed that the performance of LI-RADS for diagnosing HCC has a sensitivity of 67% and specificity of 92%. These data confirm previous reports indicating that radiologic imaging alone inaccurately stages as many as 20%-25% of patients undergoing LT for HCC [26][27][28] .…”