Clinicopathologic characterization of hepatocellular adenomas in men: a multicenter experience

Abstract

Hepatocellular adenomas (HCAs) are benign liver neoplasms which most commonly present in women in their reproductive age. In men they are rare and have a higher risk of malignant transformation to hepatocellular carcinoma (HCC), with current guidelines advocating their complete resection. Here we present our multicenter experience of HCA in men in the United States. A total of 27 HCA cases were included with a mean age of presentation of 37 years (9 - 69 years) and a mean size of 6.8 cm (0.9 - 18.5 cm). Based on the 2019 WHO classification, the most common subtype identified was inflammatory HCA (IHCA) (10 cases, 37.0%) followed by unclassified HCA (U-HCA) (7 cases, 25.9%), HNF1A-inactivated HCA (H-HCA) (6 cases, 22.2%), β-catenin activated IHCA (b-IHCA) (3 cases, 11.1%), and β-catenin activated HCA (b-HCA) (1 case, 3.7%). Six additional cases diagnosed as hepatocellular neoplasm of uncertain malignant potential (HUMP) were also included in the study. These cases presented in a mean age of 46 years (17 - 64 years) and size of 10.8 cm (4.2 - 16.5 cm). We further evaluated the significance of androgen receptor (AR) expression by immunohistochemistry (IHC); of the 16 cases with materials available, 8 were considered positive using the Allred score system (2 I-HCA, 2 H-HCA, 1 U-HCA, and 3 HUMP). Of the total cases, 12 were diagnosed on biopsies, for which follow-up information is available for 7 (47.6 months, 8 - 160 months), and none of them show evidence of malignant transformation. Of the 21 resection cases, a concomitant well differentiated hepatocellular carcinoma (HCC) within the same lesion was identified in 5 cases (23.8%) which were diagnosed as HCA (n=4) or HUMP (n=1). Overall, 15% of cases in our entire cohort of HCA and HUMP showed concomitant HCC, while none of the 7 biopsy cases showed any malignant transformation on follow-up (22 - 160 months; mean 61.8).