Genetic and epigenetic analysis of hepatocellular adenomas with atypical morphological features

BACKGROUND

Hepatocellular adenoma (HCA) is a rare liver tumour, which can have atypical morphological features such as cytological atypia, pseudoglandular architecture, and altered reticulin framework. Little is known about the genetic and epigenetic alterations of such HCAs and whether they show the alterations classically found in hepatocellular carcinoma (HCC) or in HCA without atypical morphology.

METHODS

We analysed five HCAs with atypical morphological features and one HCA with transition to HCC. Every tumour was subtyped by immunohistochemistry, sequenced by a targeted NGS panel, and analysed on a DNA methylation microarray.

RESULTS

Subtyping of the five HCAs with atypical features revealed two β-catenin mutated HCA (b-HCA), two β-catenin mutated inflammatory HCA (b-IHCA), and one sonic hedgehog activated HCA (shHCA). None of them showed mutations typically found in HCC, such as, e.g. TERT or TP53 mutations. The epigenomic pattern of HCAs with atypical morphological features clustered with reference data for HCAs without atypical morphological features but not with HCC. Similarly, phyloepigenetic trees using the DNA methylation data reproducibly showed that HCAs with morphological atypia are much more similar to nonmalignant samples than to malignant samples. Finally, atypical HCAs showed no relevant copy number variations (CNV).

CONCLUSION

In our series, mutational, DNA methylation, as well as CNV analyses, supported a relationship of atypical HCAs with nonatypical HCAs rather than with HCC. Therefore, in cases with difficult differential diagnosis between HCC and HCA, it might be advisable to perform targeted sequencing and/or combined methylation/copy number profiling.

Histologic parameter score does not predict short-term survival in severe alcoholic hepatitis

BACKGROUND AND AIM

The alcoholic hepatitis histologic score has been proposed as a new prognostic tool to assess the risk of death in alcoholic hepatitis. We aimed to evaluate its prognostic value in patients with severe alcoholic hepatitis.

METHODS

Liver biopsies were analysed independently by two pathologists according to the alcoholic hepatitis histologic score. The Laennec staging system was also used to evaluate fibrosis.

RESULTS

One hundred and seven patients were included, and 89% of the patients received corticosteroids. The alcoholic hepatitis histologic score was available in 105 patients. Histologic scoring showed mild, moderate and severe scores in 10, 29 and 66 patients, respectively. Laennec staging was available for 53 patients, among whom 49 had cirrhosis, including 7 with Laennec 4A, 15 with 4B and 27 with 4C. Survival rates in mild, moderate and severe alcoholic hepatitis histologic score groups were 90%, 72% and 69% at 28 days (p = 0.6), 80%, 52% and 63% at 3 months (p = 0.3), and 70%, 41% and 58% at 6 months (p = 0.3), respectively. Within the alcoholic hepatitis histologic score, fibrosis demonstrated the best interobserver reproducibility (agreement = 100%, Κ = 1.00). Compared to patients with Laennec 4B or 4C cirrhosis, survival rates for patients without cirrhosis or with Laennec 4A cirrhosis were 100% vs 83% at 28 days (p = 0.16), 91% vs 68% at 3 months (p = 0.13), and 82% vs 64% at 6 months (p = 0.2), respectively. In multivariate analysis adjusted for age and for model for end-stage liver disease score, the alcoholic hepatitis histologic score and Laennec stage were not associated with 6-month mortality.

CONCLUSIONS

The alcoholic hepatitis histologic score is not predictive of short-term survival in this cohort of patients with severe alcoholic hepatitis.

Hepatic manifestations of Wilson's disease: 12-year experience in a Swiss tertiary referral centre

BACKGROUND AND AIM

Wilson’s disease is an inherited disorder of hepatic copper metabolism, leading to the accumulation of copper in the liver as well as the brain, cornea and other organs. Here, we describe the adult cases of hepatic Wilson’s disease diagnosed at the Division of Gastroenterology and Hepatology of the University Hospital Lausanne, Switzerland between September 2004 and August 2016.

METHODS

Clinical manifestations, results of diagnostic tests, management and outcomes of adult patients with hepatic Wilson’s disease were assessed based on standardised medical records. In addition, liver histology was reviewed and the lesional patterns were recorded.

RESULTS

Ten new adult cases of hepatic Wilson’s disease were diagnosed in our centre between September 2004 and August 2016. Male to female ratio was 1:1 and median age at diagnosis was 26 (range 18–56) years. Four patients presented with acute liver failure, four with persistently elevated liver function tests, and two with decompensated cirrhosis; none had neurological manifestations. Only one patient had a Kayser-Fleischer corneal ring. Median ceruloplasmin level at diagnosis was 0.13 (range <0.03–0.30) g/l, median 24-hour urinary copper excretion was 2.8 (range 0.3–77.3) μmol, and median hepatic copper concentration was 789 (range 284–1677) μg/g. At least one mutation in the ATP7B gene was identified in eight patients. Allelic frequency of the common H1069Q mutation was 19%. Leipzig score was ≥5 in all patients. Three patients presenting with acute liver failure and the two with decompensated cirrhosis underwent successful liver transplantation. One patient with acute liver failure recovered under chelation therapy, as predicted by a Dhawan score <11. D-penicillamine was used as first-line chelator treatment, with a subsequent switch to trientine due to adverse effects in three out of six patients.

CONCLUSIONS

The clinical presentation of hepatic Wilson’s disease is highly variable. Three out of 10 patients were diagnosed at an age >35 years. A high index of suspicion in clinically compatible situations is key.

Combination of Gene Expression Signature and Model for End-Stage Liver Disease Score Predicts Survival of Patients With Severe Alcoholic Hepatitis

BACKGROUND & AIMS

Patients with severe alcoholic hepatitis (AH) have a high risk of death within 90 days. Corticosteroids, which can cause severe adverse events, are the only treatment that increases short-term survival. It is a challenge to predict outcomes of patients with severe AH. Therefore, we developed a scoring system to predict patient survival, integrating baseline molecular and clinical variables.

METHODS

We obtained fixed liver biopsy samples from 71 consecutive patients diagnosed with severe AH and treated with corticosteroids from July 2006 through December 2013 in Brussels, Belgium (derivation cohort). Gene expression patterns were analyzed by microarrays and clinical data were collected for 180 days. We identified gene expression signatures and clinical data that are associated with survival without liver transplantation at 90 and 180 days after initiation of corticosteroid therapy. Findings were validated using liver biopsies from 48 consecutive patients with severe AH treated with corticosteroids, collected from March 2010 through February 2015 at hospitals in Belgium and Switzerland (validation cohort 1) and in liver biopsies from 20 patients (9 received corticosteroid treatment), collected from January 2012 through May 2015 in the United States (validation cohort 2).

RESULTS

We integrated data on expression patterns of 123 genes and the model for end-stage liver disease (MELD) scores to assign patients to groups with poor survival (29% survived 90 days and 26% survived 180 days) and good survival (76% survived 90 days and 65% survived 180 days) (P < .001) in the derivation cohort. We named this assignment system the gene signature-MELD (gs-MELD) score. In validation cohort 1, the gs-MELD score discriminated patients with poor survival (43% survived 90 days) from those with good survival (96% survived 90 days) (P < .001). The gs-MELD score also discriminated between patients with a poor survival at 180 days (34% survived) and a good survival at 180 days (84% survived) (P < .001). The time-dependent area under the receiver operator characteristic curve for the score was 0.86 (95% confidence interval 0.73-0.99) for survival at 90 days, and 0.83 (95% confidence interval 0.71-0.96) for survival at 180 days. This score outperformed other clinical models to predict survival of patients with severe AH in validation cohort 1. In validation cohort 2, the gs-MELD discriminated patients with a poor survival at 90 days (12% survived) from those with a good survival at 90 days (100%) (P < .001).

CONCLUSIONS

We integrated data on baseline liver gene expression pattern and the MELD score to create the gs-MELD scoring system, which identifies patients with severe AH, treated or not with corticosteroids, most and least likely to survive for 90 and 180 days.

Focal β-catenin mutation identified on formalin-fixed and paraffin-embedded inflammatory hepatocellular adenomas

The identification of hepatocellular adenoma (HCA) with mutation in exon 3 of the CTNNB1 gene encoding for β-catenin is clinically relevant due to a higher risk of malignant transformation. Inflammatory HCA (IHCA) can exhibit β-catenin activation (β-IHCA). We report two cases with multiple IHCA in which focal β-catenin activation has been found in one of the IHCA. In both cases, the diagnosis of IHCA was confirmed on the resected nodules by routine stains, immunohistochemical detection of C-reactive protein (CRP) and molecular biology on frozen material. An additional molecular analysis was performed on formalin-fixed paraffin-embedded (FFPE) material that showed focal glutamine synthetase (GS) staining, the surrogate marker of β-catenin activation. In case 1, it was a 1.8-cm area within the 7.5 cm IHCA, and in case 2 a small 0.3-cm area within a 1.8 cm resected IHCA located close to a larger IHCA, negative for GS. In both cases, nuclear β-catenin expression and decreased reticulin network were observed in the GS expressing foci, together with cholestasis and diffuse CD34 expression in case 1. Molecular analysis by pyrosequencing on FFPE material using the GS-stained slides as reference to select areas with/without positive staining revealed a CTNNB1 exon 3 mutation restricted to the areas exhibiting both positive GS and CRP expression, whereas wild-type CTNNB1 was found in areas showing only CRP staining. These two cases illustrate focal β-catenin activation that can occur within IHCAs. Additional data are needed to determine if β-catenin mutation is a secondary event in IHCA.

Amazon rain-forest fires

Charcoal is common in the soils of mature rain forests within 75 kilometers of San Carlos de Rio Negro in the north central Amazon Basin. Carbon-14 dates of soil charcoal from this region indicate that numerous fires have occurred since the mid-Holocene epoch. Charcoal is most common in tierra firme forest Oxisols and Ultisols and less common in caatinga and igapo forest soils. Climatic changes or human activities, or both, have caused rain-forest fires.