HCA was considered steatotic (suggesting HNF-1α-mutated HCA) check details when diffuse and homogeneous signal dropout was observed on chemical shift sequences.18 HCA was considered telangiectatic/inflammatory when the lesion exhibited a marked high intensity signal on T2-weighted sequences, associated with delayed persistent enhancement.18 HCA was considered unclassified when the lesion did not display the MRI pattern typical of steatotic or telangiectatic/inflammatory HCAs. Final diagnosis and subtyping of HCAs was based

on examination of the surgical specimen. All liver resections underwent macroscopic analysis and tissue sampling of both the tumoral and nontumoral liver was performed. Histological diagnosis of HCA was defined as a tumor composed of benign hepatocytes arranged in regular

plates of one or two cells thick, outlined by a preserved reticulin’s framework, with numerous unpaired arteries. No portal tracts were present. The following markers were used for immunohistochemistry: SAA (Dako, 1:25 dilution), LFABP (Abcam, 1:20 dilution), β-catenin Selleckchem ATR inhibitor (BD Biosciences, dilution 1:200), and glutamine synthetase (Chemicon, 1:500 dilution) to improve the diagnostic accuracy of β-catenin activation. HCA subtyping into telangiectatic/inflammatory (SAA-positive), steatotic (LFABP-negative), and unclassified HCA (HCA without any specific morphological or immunophenotypical features) Niclosamide was performed according to previously described criteria including morphological

and immunophenotypical features.4, 12 β-Catenin activation was assessed by immunohistochemistry in all HCAs whatever the presence of cell atypias and was considered activated when nuclear staining of tumoral hepatocytes was observed. When discordances were observed between morphological and immunophenotypical features, morphological features, if characteristic, were considered for subtyping.4 The nontumoral liver was systematically reviewed. Four senior radiologists with more than 10 years of experience in abdominal imaging performed liver biopsy at our institution. Patient sedation (10 mg of diazepam) was administered 1-2 hours before the procedure.