Diagnostic Performance of LI-RADS for MRI and CT Detection of HCC: A Systematic Review and Diagnostic Meta-analysis

Abstract Purpose To perform a meta-analysis evaluating the diagnostic accuracy of the Liver Imaging Reporting and Data System (LI-RADS) for detecting hepatocellular carcinoma (HCC). Method A systematic PubMed/Embase/Web of Science electronic database search was performed for original diagnostic studies published through July 31, 2018. Statistical analysis included data pooling, forest plot construction, heterogeneity testing, meta-regression, and subgroup analyses. Results Eighteen studies involving 3386 patients were included in the meta-analysis. The pooled sensitivity and specificity of LI-RADS (v2011, v2014 and v2017) were 0.86 (95% CI: 0.78-0.91) and 0.85 (95% CI: 0.78-0.90), respectively, for diagnosing HCC. The area under the curve (AUC) was 0.92 (95% CI: 0.89-0.94). Meta-regression analysis showed that the publication year, blinding to the reference standard and the number of readers were significant factors affecting heterogeneity. In subgroup analyses, MRI demonstrated higher sensitivity (0.82 vs. 0.73) and comparable specificity (0.79 vs. 0.78) over CT. For HCCs ≤30 mm, LI-RADS showed lower sensitivity of 0.72 and specificity of 0.80 compared with HCC of all sizes. LR-5 showed higher sensitivity (0.67) and specificity (0.93) than LR-3 and LR-4. LR ≥ 5 had higher specificity (0.94) at the cost of decreased sensitivity (0.66) than LR ≥ 3 and LR ≥ 4. Conclusions LI-RADS shows high diagnostic accuracy in diagnosing of HCC with a pooled sensitivity of 0.86 and specificity of 0.85, and specificity is higher for LR-5 or LR ≥ 5. However, further prospective studies of LI-RADS are needed to elucidate its value for diagnosing of small HCCs (≤20 mm).