Risk Factors for Bleeding Hepatocellular Adenoma in a United States Cohort.

Abstract

BACKGROUND & AIMS\nKnown risk factors for hepatocellular adenoma (HCA) bleeding are size >5cm, growth rate, visible vascularity, exophytic lesions, β-catenin and Sonic Hedgehog activated HCAs. Most studies are based on European cohorts. The objective of this study is to identify additional risk factors for HCA bleeding in a U.S. cohort.\n\n\nMETHODS\nRetrospective chart review was performed on patients\xa0diagnosed with HCA on magnetic resonance imaging (n=184) at an academic tertiary institution. Clinical, pathological, and imaging data was collected. Primary outcomes measured were HCA bleeding and malignancy. Statistical analysis was performed with SAS 9.4 using Chi Square, Fisher s exact test, sample t-test, non-parametric Wilcoxon test, and logistic regression.\n\n\nRESULTS\nAfter excluding patients whose pathology showed focal nodular hyperplasia and non-adenoma lesions, follow-up data was available for 167 patients. 16% experienced microscopic or macroscopic bleeding and 1.2% had malignancy. HCA size predicted bleeding (p<0.0001) and no patients with lesion size <1.8cm bled. In unadjusted analysis, hepatic adenomatosis (≥10 lesions) trended towards 2.8-fold increased risk of bleeding. Of patients with a single lesion that bled, 77% bled from a lesion >5cm. In patients with multiple HCAs that bled, 50% bled from lesions <5cm.\xa0In patients with multiple adenomas, size (p=0.001) independently predicted bleeding and hepatic steatosis trended towards increased risk of bleeding (p=0.05).\n\n\nCONCLUSIONS\nIn a large U.S. cohort, size predicted increased risk of HCA bleeding while hepatic adenomatosis trended towards increased risk of bleeding. In patients with multiple HCAs, size predicted bleeding and hepatic steatosis trended toward increased risk of bleeding.