An adult male patient with multiple adenomas and a hepatocellular carcinoma : mild Gycogen Storage Disease type Ia

The development of hepatocellular adenomas and – more rarely – carcinoma in the liver of patients with Glycogen Storage Disease type Ia (GSDIa) is a well-known complication of the disease. The pathophysiology of adenoma and carcinoma development in these patients is, however, hitherto largely unknown and is thought to be related to the metabolic control of the patient and/or the type of mutations in the G6PC gene. We report here on a very illustrative case of adenoma and carcinoma formation in a previously undiagnosed 42year old male GSDIa patient (enzymatically and genetically proven). He had two episodes of mild hypoglycaemia in childhood, never required formal treatment, showed normal growth, and only mild lactate increases after prolonged starvation. He was a long-distance runner for most of his adult life, without the need for more than normal carbohydrate intake before/during exertion. To gain a better view on the type of adenoma formed in this patient, molecular studies were performed. We show here that in this patient with mild GSDIa without recurrent hypoglycaemic episodes, adenoma and carcinoma formation still occurred and that malignant transformation of adenoma here is associated with CTNNB1 mutations and a typical mRNA profile of a β-catenin activated lesion

Hepatocellular carcinoma

Liver cancer is the second leading cause of cancer-related deaths globally and has an incidence of approximately 850,000 new cases per year. Hepatocellular carcinoma (HCC) represents approximately 90% of all cases of primary liver cancer. The main risk factors for developing HCC are well known and include hepatitis B and C virus infection, alcohol intake and ingestion of the fungal metabolite aflatoxin B1. Additional risk factors such as non-alcoholic steatohepatitis are also emerging. Advances in the understanding of the molecular pathogenesis of HCC have led to identification of critical driver mutations; however, the most prevalent of these are not yet druggable targets. The molecular classification of HCC is not established, and the Barcelona Clinic Liver Cancer staging classification is the main clinical algorithm for the stratification of patients according to prognosis and treatment allocation. Surveillance programmes enable the detection of early-stage tumours that are amenable to curative therapies - resection, liver transplantation or local ablation. At more developed stages, only chemoembolization (for intermediate HCC) and sorafenib (for advanced HCC) have shown survival benefits. There are major unmet needs in HCC management that might be addressed through the discovery of new therapies and their combinations for use in the adjuvant setting and for intermediate- and advanced-stage disease. Moreover, biomarkers for therapy stratification, patient-tailored strategies targeting driver mutations and/or activating signalling cascades, and validated measurements of quality of life are needed. Recent failures in the testing of systemic drugs for intermediate and advanced stages have indicated a need to refine trial designs and to define novel approaches

New insights in the management of Hepatocellular Adenoma

Hepatocellular adenoma (HCA) are benign liver tumours that may be complicated by haemorrhage or malignant transformation to hepatocellular carcinoma. Epidemiological data are fairly outdated, but it is likely to assume that the incidence has increased over the past decades as HCA are more often incidentally found due to the more widespread use of imaging techniques and the increased incidence of obesity. Various molecular subgroups have been described. Each of these molecular subgroups are defined by specific gene mutations and pathway activations. Additionally, they are all related to specific risk factors and show a various biological behaviour. These molecular subgroups may be identified using immunohistochemistry and molecular characterization. Contrast-enhanced MRI is the recommended imaging modality to analyse patients with suspected hepatocellular adenoma allowing to determine the subtype in up to 80%. Surgical resection remains to be the golden standard in treating HCA, although resection is deemed unnecessary in a large number of cases, as studies have shown that the majority of HCA will regress over time without complications such as haemorrhage or malignant transformation occurring. It is preferable to treat patients with suspected HCA in high volume centres with combined expertise of liver surgeons, hepatologists, radiologists and (molecular) pathologists

Systemic AA amyloidosis caused by inflammatory hepatocellular adenoma

To the Editor: Amyloid A (AA) systemic amyloidosis is a complication of chronic inflammatory diseases that is caused by the deposition of insoluble aggregates of cleaved N-terminal fragments of serum amyloid A (SAA) protein in tissues and organs throughout the body. Under physiologic conditions, SAA protein is produced by hepatocytes during the acute inflammatory phase in response to various cytokines such as interleukin-6. SAA is also overexpressed by neoplastic hepatocytes in inflammatory hepatocellular adenomas, a specific molecular subtype of benign liver tumors

Somatic mutations activating STAT3 in human inflammatory hepatocellular adenomas

Somatic STAT3 mutations present in a subset of inflammatory hepatocellular adenomas result in the generation of constitutively active STAT3 proteins that homodimerize independently of IL-6 stimulation

DNA methylation-based prognosis and epidrivers in hepatocellular carcinoma

Epigenetic deregulation has emerged as a driver in human malignancies. There is no clear understanding of the epigenetic alterations in hepatocellular carcinoma (HCC) and of the potential role of DNA methylation markers as prognostic biomarkers. Analysis of tumor tissue from 304 patients with HCC treated with surgical resection allowed us to generate a methylation-based prognostic signature using a training-validation scheme. Methylome profiling was done with the Illumina HumanMethylation450 array (Illumina, Inc., San Diego, CA), which covers 96% of known cytosine-phosphate-guanine (CpG) islands and 485,000 CpG, and transcriptome profiling was performed with Affymetrix Human Genome U219 Plate (Affymetrix, Inc., Santa Clara, CA) and miRNA Chip 2.0. Random survival forests enabled us to generate a methylation signature based on 36 methylation probes. We computed a risk score of mortality for each individual that accurately discriminated patient survival both in the training (221 patients; 47% hepatitis C-related HCC) and validation sets (n = 83; 47% alcohol-related HCC). This signature correlated with known predictors of poor outcome and retained independent prognostic capacity of survival along with multinodularity and platelet count. The subset of patients identified by this signature was enriched in the molecular subclass of proliferation with progenitor cell features. The study confirmed a high prevalence of genes known to be deregulated by aberrant methylation in HCC (e.g., Ras association [RalGDS/AF-6] domain family member 1, insulin-like growth factor 2, and adenomatous polyposis coli) and other solid tumors (e.g., NOTCH3) and describes potential candidate epidrivers (e.g., septin 9 and ephrin B2). Conclusions: A validated signature of 36 DNA methylation markers accurately predicts poor survival in patients with HCC. Patients with this methylation profile harbor messenger RNA-based signatures indicating tumors with progenitor cell features

Hepatocellular adenoma: what is new in 2008

Patients (85%) with hepatocellular adenoma (HCA) are women taking oral contraceptives. They can be divided into four subgroups according to their genotype/phenotype features. (1) Hepatocyte nuclear factor 1α (HNF1α) biallelic somatic mutations are observed in 35% of the HCA cases. It occurs in almost all cases in women. HNF1α-mutated HCA are most of the time, highly steatotic, with a lack of expression of liver fatty acid binding protein (LFABP) in immunohistochemistry analyses. Adenomatosis is frequently detected in this context. An HNF1α germline mutation is observed in less than 5% of HCA cases and can be associated with MODY 3 diabetes. (2) An activating β-catenin mutation was found in 10% of HCA. These β-catenin activated HCAs are observed in men and women, and specific risk factors, such as male hormone administration or glycogenosis, are associated with their development. Immunohistochemistry studies show that these HCAs overexpress β-catenin (nuclear and cytoplasmic) and glutamine synthetase. This group of tumours has a higher risk of malignant transformation into hepatocellular carcinoma. (3) Inflammatory HCAs are observed in 40% of the cases, and they are most frequent in women but are also found in men. Lesions are characterised by inflammatory infiltrates, dystrophic arteries, sinusoidal dilatation and ductular reaction. They express serum amyloid A and C-reactive protein. In this group, GGT is frequently elevated, with a biological inflammatory syndrome present. Also, there are more overweight patients in this group. An additional 10% of inflammatory HCAs express β-catenin, and are also at risk of malignant transformation. (4) Currently, less than 10% of HCAs are unclassified. It is hoped that in the near future it will be possible with clinical, biological and imaging data to predict in which of the 2 major groups (HNF1α-mutated HCA and inflammatory HCA) the patient belongs and to propose better guidelines in terms of surveillance and treatment

Unique genomic profile of fibrolamellar hepatocellular carcinoma

BACKGROUND & AIMS: Fibrolamellar hepatocellular carcinoma (FLC) is a rare primary hepatic cancer that develops in children and young adults without cirrhosis. Little is known about its pathogenesis, and it can be treated only with surgery. We performed an integrative genomic analysis of a large series of patients with FLC to identify associated genetic factors. METHODS: By using 78 clinically annotated FLC samples, we performed whole-transcriptome (n = 58), single-nucleotide polymorphism array (n = 41), and next-generation sequencing (n = 48) analyses; we also assessed the prevalence of the DNAJB1-PRKACA fusion transcript associated with this cancer (n = 73). We performed class discovery using non-negative matrix factorization, and functional annotation using gene-set enrichment analyses, nearest template prediction, ingenuity pathway analyses, and immunohistochemistry. The genomic identification of significant targets in a cancer algorithm was used to identify chromosomal aberrations, MuTect and VarScan2 were used to identify somatic mutations, and the random survival forest was used to determine patient prognoses. Findings were validated in an independent cohort. RESULTS: Unsupervised gene expression clustering showed 3 robust molecular classes of tumors: the proliferation class (51% of samples) had altered expression of genes that regulate proliferation and mammalian target of rapamycin signaling activation; the inflammation class (26% of samples) had altered expression of genes that regulate inflammation and cytokine enriched production; and the unannotated class (23% of samples) had a gene expression signature that was not associated previously with liver tumors. Expression of genes that regulate neuroendocrine function, as well as histologic markers of cholangiocytes and hepatocytes, were detected in all 3 classes. FLCs had few copy number variations; the most frequent were focal amplification at 8q24.3 (in 12.5% of samples), and deletions at 19p13 (in 28% of samples) and 22q13.32 (in 25% of samples). The DNAJB1-PRKACA fusion transcript was detected in 79% of samples. FLC samples also contained mutations in cancer-related genes such as BRCA2 (in 4.2% of samples), which are uncommon in liver neoplasms. However, FLCs did not contain mutations most commonly detected in liver cancers. We identified an 8-gene signature that predicted survival of patients with FLC. CONCLUSIONS: In a genomic analysis of 78 FLC samples, we identified 3 classes based on gene expression profiles. FLCs contain mutations and chromosomal aberrations not previously associated with liver cancer, and almost 80% contain the DNAJB1-PRKACA fusion transcript. By using this information, we identified a gene signature that is associated with patient survival time

Toward understanding and exploiting tumor heterogeneity

The extent of tumor heterogeneity is an emerging theme that researchers are only beginning to understand. How genetic and epigenetic heterogeneity affects tumor evolution and clinical progression is unknown. The precise nature of the environmental factors that influence this heterogeneity is also yet to be characterized. Nature Medicine, Nature Biotechnology and the Volkswagen Foundation organized a meeting focused on identifying the obstacles that need to be overcome to advance translational research in and tumor heterogeneity. Once these key questions were established, the attendees devised potential solutions. Their ideas are presented here