No abstract

Fibrosis is a common endpoint of clinical trials in chronic hepatitis C, and liver biopsy remains the gold standard for fibrosis evaluation. However, variability in the distribution of fibrosis within the liver is a potential limitation. Our aim was to assess the heterogeneity of liver fibrosis and its influence on the accuracy of assessment of fibrosis with liver biopsy. Surgical samples of livers from patients with chronic hepatitis C were studied. Measurement of fibrosis was performed on the whole section by using both image analysis and METAVIR score (reference value). From the digitized image of the whole section, virtual biopsy specimens of increasing length were produced. Fibrosis was assessed independently on each individual virtual biopsy specimen. Results were compared with the reference value according to the length of the biopsy specimen. By using image analysis, the coefficient of variation of fibrosis measurement with 15-mm long biopsy specimens was 55%; and for biopsy specimens of 25-mm length it was 45%. By using the METAVIR scoring system, 65% of biopsies 15 mm in length were categorized correctly according to the reference value. This increased to 75% for a 25-mm liver biopsy specimen without any substantial benefit for longer biopsy specimens. Sampling variability of fibrosis is a significant limitation in the assessment of fibrosis with liver biopsy. In conclusion, this study suggests that a length of at least 25 mm is necessary to evaluate fibrosis accurately with a semiquantitative score. Sampling variability becomes a major limitation when using more accurate methods such as automated image analysis.

Link to publication on Research at Birmingham portal General rights Unless a licence is specified above, all rights (including copyright and moral rights) in this document are retained by the authors and/or the copyright holders. The express permission of the copyright holder must be obtained for any use of this material other than for purposes permitted by law. • Users may freely distribute the URL that is used to identify this publication. • Users may download and/or print one copy of the publication from the University of Birmingham research portal for the purpose of private study or non-commercial research. • User may use extracts from the document in line with the concept of 'fair dealing' under the Copyright, Designs and Patents Act 1988 (?) • Users may not further distribute the material nor use it for the purposes of commercial gain. Where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document. When citing, please reference the published version. Take down policy While the University of Birmingham exercises care and attention in making items available there are rare occasions when an item has been uploaded in error or has been deemed to be commercially or otherwise sensitive.

Hepatocellular adenomas are benign tumors that can be difficult to diagnose. To refine their classification, we performed a comprehensive analysis of their genetic, pathological, and clinical features. A multicentric series of 96 liver tumors with a firm or possible diagnosis of hepatocellular adenoma was reviewed by liver pathologists. In all cases, the genes coding for hepatocyte nuclear factor 1␣ (HNF1␣) and ␤-catenin were sequenced. No tumors were mutated in both HNF1␣ and ␤-catenin enabling tumors to be classified into 3 groups, according to genotype. Tumors with HNF1␣ mutations formed the most important group of adenomas (44 cases). They were phenotypically characterized by marked steatosis (P < 10 ؊4 ), lack of cytological abnormalities (P < 10 ؊6 ), and no inflammatory infiltrates (P < 10 ؊4 ). In contrast, the group of tumors defined by ␤-catenin activation included 13 lesions with frequent cytological abnormalities and pseudo-glandular formation (P < 10 ؊5 ). The third group of tumors without mutation was divided into two subgroups based on the presence of inflammatory infiltrates. The subgroup of tumors consisting of 17 inflammatory lesions, resembled telangiectatic focal nodular hyperplasias, with frequent cytological abnormalities (P ‫؍‬ 10 ؊3 ), ductular reaction (P < 10 ؊2 ), and dystrophic vessels (P ‫؍‬ .02). In this classification, hepatocellular carcinoma associated with adenoma or borderline lesions between carcinoma and adenoma is found in 46% of the ␤-catenin-mutated tumors whereas they are never observed in inflammatory lesions and are rarely found in HNF1␣ mutated tumors (P ‫؍‬ .004). In conclusion, the molecular and pathological classification of hepatocellular adenomas permits the identification of strong genotype-phenotype correlations and suggests that adenomas with ␤-catenin activation have a higher risk of malignant transformation. (

Nonalcoholic fatty liver disease (NAFLD) is highly prevalent and being overweight is a significant risk factor. The aim was to build an algorithm along with a scoring system for histopathologic classification of liver lesions that covers the entire spectrum of lesions in morbidly obese patients. A cohort of 679 obese patients undergoing liver biopsy at the time of bariatric surgery was studied. An algorithm for segregating lesions into normal liver, NAFLD, or nonalcoholic steatohepatitis (NASH) was built based on semiquantitative evaluation of steatosis, hepatocellular ballooning, and lobular inflammation. For each case, the SAF score was created including the semiquantitative scoring of steatosis (S), activity (A), and fibrosis (F). Based on the algorithm, 230 obese patients (34%) were categorized as NASH, 291 (43%) as NAFLD without NASH, and 158 (23%) as not NAFLD. The activity score (ballooning 1 lobular inflammation) enabled discriminating NASH because all patients with NASH had A ! 2, whereas no patients with A < 2 had NASH. This score was closely correlated with both alanine aminotransferase (ALT) and aspartate aminotransferase (AST) (P < 0.0001, analysis of variance [ANOVA]). Comparison of transaminase levels between patients with normal liver and pure steatosis did not reveal significant differences, thus lending support to the proposal not to include steatosis in the activity score but to report it separately in the SAF score. In the validation series, the interobserver agreement for the diagnosis of NASH was excellent (j 5 0.80) between liver pathologists. There was no discrepancy between the initial diagnosis and the diagnosis proposed using the algorithm. Conclusion: We propose a simple but robust algorithm for categorizing liver lesions in NAFLD patients. Because liver lesions in obese patients may display a continuous spectrum of histologic lesions, we suggest describing liver lesions using the SAF score.

No abstract

No abstract

Using sequencing and gene expression analyses, we identified a subgroup of HCA characterized by fusion of the INHBE and GLI1 genes and activation of sonic hedgehog pathway. Molecular subtypes of HCAs associated with different patients' risk factors for HCA, disease progression, and pathology features of tumors. This classification system might be used to select treatment strategies for patients with HCA.