Tumor size-based validation of contrast-enhanced ultrasound liver imaging reporting and data system (CEUS LI-RADS) 2017 for hepatocellular carcinoma characterizing

Objectives: To validate the efficacy of contrast-enhanced ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS) and its major features in diagnosing hepatocellular carcinoma (HCC) of different sizes in high-risk patients. Methods: Between January 2014 and December 2015, a total of 545 untreated liver nodules were included. These liver nodules were divided into two groups (<20 mm and ≥20 mm). Each nodule was classified based on CEUS LI-RADS. The diagnostic performance comparison was assessed by the chi-square test, with pathology results as the golden criterion. Results: The accuracy, sensitivity, specificity, and positive predictive value (PPV) of CEUS LR-5 criteria in <20 mm group vs ≥20 mm group in diagnosing HCC were 60.5% vs 59.8%, 55.6% vs 57.6%, 85.7% vs 88.6 and 95.2% vs 98.5%, respectively, without significant difference (all p > 0.05). The accuracy, sensitivity and PPV of LR5/M for malignancy in <20 mm group were lower than in ≥20 mm group, with values of 79.1% vs 95.0%, 84.2% vs 95.7 and 91.4% vs 99.2%, respectively (p < 0.05). Conclusions: The CEUS LI-RADS has a comparable performance for diagnosing HCC between lesions ≥ 20 mm and <20 mm. For diagnosing malignancy including HCC, it has a higher efficacy for lesions ≥ 20 mm than <20 mm. Advances in knowledge: 1.For diagnosing HCC, CEUS LI-RADS has comparable performances between lesions ≥ 20 mm and <20 mm. 2. For diagnosing malignancy including HCC, CEUS LI-RADS has a higher efficacy for lesions ≥ 20 mm than <20 mm.