Hepatospecific Mr Contrast Agent Uptake On Hepatobiliary Phase Can Be Used As A Biomarker Of Marked Beta-Catenin Activation In Hepatocellular Adenoma

Objectives To assess the value of hepatospecific MR contrast agent uptake on hepatobiliary phase (HBP) images to detect marked activation of the beta-catenin pathway in hepatocellular adenomas (HCAs). Methods This multicentric retrospective IRB-approved study included all patients with a pathologically proven HCA who underwent gadobenate dimeglumine-enhanced liver MRI with HBP. Tumor signal intensity on HBP was first assessed visually, and lesions were classified into three distinct groups-hypointense, isointense, or hyperintense-according to the relative signal intensity to liver. Uptake was then quantified using the lesion-to-liver contrast enhancement ratio (LLCER). Finally, the accuracy of HBP analysis in depicting marked beta-catenin activation in HCA was evaluated. Results A total of 124 HCAs were analyzed including 12 with marked beta-catenin activation (HCA B+). Visual analysis classified 94/124 (76%), 12/124 (10%), and 18/124 (14%) HCAs as being hypointense, isointense, and hyperintense on HBP, respectively. Of these, 1/94 (1%), 3/12 (25%), and 8/18 (44%) were HCA B+, respectively (p < 0.001). The LLCER of HCA B+ was higher than that of HCA without marked beta-catenin activation in the entire cohort (means 4.9 +/- 11.8% vs. - 19.8 +/- 11.4%, respectively, p < 0.001). A positive LLCER, i.e., LLCER >= 0%, had 75% (95% CI 43-95%) sensitivity and 97% (95% CI 92-99%) specificity, with a LR+ of 28 (95% CI 8.8-89.6) for the diagnosis of HCA B+. Conclusions Hepatospecific contrast uptake on hepatobiliary phase is strongly associated with marked activation of the beta-catenin pathway in hepatocellular adenoma, and its use might improve hepatocellular adenoma subtyping on MRI.