Appearance of hepatocellular carcinoma on gadoxetic acid-enhanced hepato-biliary phase MR imaging: a systematic review

Objective: To perform a systematic review of the contrast behaviour of HCC on Gd-EOB-DTPA hepato-biliary phase MRI. Materials and methods: This review was completed in accordance with the recommendations outlined in the preferred reporting items for systematic reviews statement. In all reports, qualitative analysis of signal intensity (SI) of HCC on hepato-biliary phase was performed: the relative SI of HCC. When available, a quantitative analysis of tumour enhancement was evaluated. Results: A total of 106 studies were retrieved, of which 41 met the inclusion criteria. The total number of patients was 2550, with 3132 HCC. MRI showed 3110 HCC (22 non-detected). 2692/3110 (87 %) HCC were hypointense on Gd-EOB-DTPA-enhanced hepatocyte-phase MRI, 134 (4 %) isointense; 106 (3 %) hyperintense and 178 (6 %) iso-hyperintense. In 26 articles, 1653 HCCs were classified as follows: 519 well-differentiated, 883 moderately differentiated, 251 poorly differentiated. Among well-differentiated HCC, 445 (86 %) were hypointense, 12 isointense (2 %), 9 hyperintense (2 %), 53 iso/hyperintense (10 %). Among moderately differentiated HCC, 774 (88 %) were hypointense, 8 isointense (1 %), 27 hyperintense (3 %), 74 iso/hyperintense (8 %). Among poorly differentiated HCCs, 245 (98 %) were hypointense, one isointense, one hyperintense and four iso-hyperintense (2 %). We found a Chi-square (?2) equivalent to 25,082 (p < 0.001). Conclusion: The percentage of lesions iso/hyper/iso-hyper is the same when considering well-differentiated and moderately differentiated HCC; when considering poorly differentiated HCC, the percentage of lesions iso/hyper/iso-hyper is significantly lower. Conversely, the percentage of lesions hypointense is significantly more represented in poorly differentiated HCC compared to well-differentiated and moderately differentiated HCC.