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36 result(s) for "Wendum Dominique"
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Gemcitabine and oxaliplatin with or without cetuximab in advanced biliary-tract cancer (BINGO): a randomised, open-label, non-comparative phase 2 trial
Gemcitabine plus a platinum-based agent (eg, cisplatin or oxaliplatin) is the standard of care for advanced biliary cancers. We investigated the addition of cetuximab to chemotherapy in patients with advanced biliary cancers. In this non-comparative, open-label, randomised phase 2 trial, we recruited patients with locally advanced (non-resectable) or metastatic cholangiocarcinoma, gallbladder carcinoma, or ampullary carcinoma and a WHO performance status of 0 or 1 from 18 hospitals across France and Germany. Eligible patients were randomly assigned (1:1) centrally with a minimisation procedure to first-line treatment with gemcitabine (1000 mg/m2) and oxaliplatin (100 mg/m2) with or without cetuximab (500 mg/m2), repeated every 2 weeks until disease progression or unacceptable toxicity. Randomisation was stratified by centre, primary site of disease, disease stage, and previous treatment with curative intent or adjuvant therapy. Investigators who assessed treatment response were not masked to group assignment. The primary endpoint was the proportion of patients who were progression-free at 4 months, analysed by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00552149. Between Oct 10, 2007, and Dec 18, 2009, 76 patients were assigned to chemotherapy plus cetuximab and 74 to chemotherapy alone. 48 (63%; 95% CI 52–74) patients assigned to chemotherapy plus cetuximab and 40 (54%; 43–65) assigned to chemotherapy alone were progression-free at 4 months. Median progression-free survival was 6·1 months (95% CI 5·1–7·6) in the chemotherapy plus cetuximab group and 5·5 months (3·7–6·6) in the chemotherapy alone group. Median overall survival was 11·0 months (9·1–13·7) in the chemotherapy plus cetuximab group and 12·4 months (8·6–16·0) in the chemotherapy alone group. The most common grade 3–4 adverse events were peripheral neuropathy (in 18 [24%] of 76 patients who received chemotherapy plus cetuximab vs ten [15%] of 68 who received chemotherapy alone), neutropenia (17 [22%] vs 11 [16%]), and increased aminotransferase concentrations (17 [22%] vs ten [15%]). 70 serious adverse events were reported in 39 (51%) of 76 patients who received chemotherapy plus cetuximab (34 events in 19 [25%] patients were treatment-related), whereas 41 serious adverse events were reported in 25 (35%) of 71 patients who received chemotherapy alone (20 events in 12 [17%] patients were treatment-related). One patient died of atypical pneumonia related to treatment in the chemotherapy alone group. The addition of cetuximab to gemcitabine and oxaliplatin did not seem to enhance the activity of chemotherapy in patients with advanced biliary cancer, although it was well tolerated. Gemcitabine and platinum-based combination should remain the standard treatment option. Institut National du Cancer, Merck Serono.
Testing for ROS1, ALK, MET, and HER2 rearrangements and amplifications in a large series of biliary tract adenocarcinomas
Biliary tract carcinomas are divided into intrahepatic, perihilar, distal extrahepatic cholangiocarcinomas, and gallbladder adenocarcinomas. Therapies targeting ROS1, ALK, MET, and HER2 alterations are currently evaluated in clinical trials. We assessed ROS1 and ALK translocations/amplifications as well as MET and HER2 amplifications for each tumor subtype by fluorescent in situ hybridization (FISH) and immunohistochemistry (IHC) in 73 intrahepatic, 40 perihilar bile duct, 36 distal extrahepatic cholangiocarcinomas, and 45 gallbladder adenocarcinomas (n = 194). By FISH, we detected targetable alterations in 5.2% of cases (n = 10): HER2 and MET amplifications were found in 4.1% (n = 8) and 1.0% (n = 2), respectively. The HER2-amplified cases were mostly gallbladder adenocarcinomas (n = 5). The MET- and HER2-amplified cases were all positive by IHC. Fourteen cases without MET amplification were positive by IHC, whereas HER2 over-expression was detected by IHC only in HER2-amplified cases. We detected no ALK or ROS1 translocation or amplification. Several alterations were consistent with aneuploidy: 24 cases showed only one copy of ROS1 gene, 4 cases displayed a profile of chromosomal instability, and an over-representation of centromeric alpha-satellite sequences was found in five cases. We confirm a relatively high rate of HER2 amplifications in gallbladder adenocarcinomas and the efficacy of IHC to screen these cases. Our results also suggest the value of IHC to screen MET amplification. Contrary to initial publications, ROS1 rearrangements seem to be very rare in biliary tract adenocarcinomas. We confirm a relatively high frequency of aneuploidy and chromosomal instability and reveal the over-representation of centromeric alpha-satellite sequences in intrahepatic cholangiocarcinomas.
Diagnosing Nodular Regenerative Hyperplasia of the Liver Is Thwarted by Low Interobserver Agreement
Nodular regenerative hyperplasia (NRH) of the liver is associated with several diseases and drugs. Clinical symptoms of NRH may vary from absence of symptoms to full-blown (non-cirrhotic) portal hypertension. However, diagnosing NRH is challenging. The objective of this study was to determine inter- and intraobserver agreement on the histopathologic diagnosis of NRH. Liver specimens (n=48) previously diagnosed as NRH, were reviewed for the presence of NRH by seven pathologists without prior knowledge of the original diagnosis or clinical background. The majority of the liver specimens were from thiopurine using inflammatory bowel disease patients. Histopathologic features contributing to NRH were also assessed. Criteria for NRH were modified by consensus and subsequently validated. Interobserver agreement was evaluated by using the standard kappa index. After review, definite NRH, inconclusive NRH and no NRH were found in 35% (23-40%), 21% (13-27%) and 44% (38-56%), respectively (median, IQR). The median interobserver agreement for NRH was poor (κ = 0.20, IQR 0.14-0.28). The intraobserver variability on NRH ranged between 14% and 71%. After modification of the criteria and exclusion of biopsies with technical shortcomings, the interobserver agreement on the diagnosis NRH was fair (κ = 0.45). The interobserver agreement on the histopathologic diagnosis of NRH was poor, even when assessed by well-experienced liver pathologists. Modification of the criteria of NRH based on consensus effort and exclusion of biopsies of poor quality led to a fairly increased interobserver agreement. The main conclusion of this study is that NRH is a clinicopathologic diagnosis that cannot reliably be based on histopathology alone.
Prominent contribution of portal mesenchymal cells to liver fibrosis in ischemic and obstructive cholestatic injuries
Liver fibrosis is produced by myofibroblasts of different origins. In culture models, rat myofibroblasts derived from hepatic stellate cells (HSCs) and from periductal portal mesenchymal cells, show distinct proliferative and immunophenotypic evolutive profiles, in particular regarding desmin microfilament (overexpressed vs shut-down, respectively). Here, we examined the contributions of both cell types, in two rat models of cholestatic injury, arterial liver ischemia and bile duct ligation (BDL). Serum and (immuno)histochemical hepatic analyses were performed at different time points (2 days, 1, 2 and 6 weeks) after injury induction. Cholestatic liver injury, as attested by serum biochemical tests, was moderate/resolutive in ischemia vs severe and sustained in BDL. Spatio-temporal and morphometric analyses of cytokeratin-19 and Sirius red stainings showed that in both models, fibrosis accumulated around reactive bile ductules, with a significant correlation between the progression rates of fibrosis and of the ductular reaction (both higher in BDL). After 6 weeks, fibrosis was stabilized and did not exceed F2 (METAVIR) in arterial ischemia, whereas micronodular cirrhosis (F4) was established in BDL. Immuno-analyses of α-smooth muscle actin and desmin expression profiles showed that intralobular HSCs underwent early phenotypic changes marked by desmin overexpression in both models and that the accumulation of fibrosis coincided with that of α-SMA-labeled myofibroblasts around portal/septal ductular structures. With the exception of desmin-positive myofibroblasts located at the portal/septal-lobular interface at early stages, and of myofibroblastic HSCs detected together with fine lobular septa in BDL cirrhotic liver, the vast majority of myofibroblasts were desmin-negative. These findings suggest that both in resolutive and sustained cholestatic injury, fibrosis is produced by myofibroblasts that derive predominantly from portal/periportal mesenchymal cells. While HSCs massively undergo phenotypic changes marked by desmin overexpression, a minority fully converts into matrix-producing myofibroblasts, at sites, which however may be important in the healing process that circumscribes wounded hepatocytes.
Diet‐Induced Dysbiosis and Genetic Background Synergize With Cystic Fibrosis Transmembrane Conductance Regulator Deficiency to Promote Cholangiopathy in Mice
The most typical expression of cystic fibrosis (CF)–related liver disease is a cholangiopathy that can progress to cirrhosis. We aimed to determine the potential impact of environmental and genetic factors on the development of CF‐related cholangiopathy in mice. Cystic fibrosis transmembrane conductance regulator (Cftr)−/− mice and Cftr+/+ littermates in a congenic C57BL/6J background were fed a high medium‐chain triglyceride (MCT) diet. Liver histopathology, fecal microbiota, intestinal inflammation and barrier function, bile acid homeostasis, and liver transcriptome were analyzed in 3‐month‐old males. Subsequently, MCT diet was changed for chow with polyethylene glycol (PEG) and the genetic background for a mixed C57BL/6J;129/Ola background (resulting from three backcrosses), to test their effect on phenotype. C57BL/6J Cftr−/− mice on an MCT diet developed cholangiopathy features that were associated with dysbiosis, primarily Escherichia coli enrichment, and low‐grade intestinal inflammation. Compared with Cftr+/+ littermates, they displayed increased intestinal permeability and a lack of secondary bile acids together with a low expression of ileal bile acid transporters. Dietary‐induced (chow with PEG) changes in gut microbiota composition largely prevented the development of cholangiopathy in Cftr−/− mice. Regardless of Cftr status, mice in a mixed C57BL/6J;129/Ola background developed fatty liver under an MCT diet. The Cftr−/− mice in the mixed background showed no cholangiopathy, which was not explained by a difference in gut microbiota or intestinal permeability, compared with congenic mice. Transcriptomic analysis of the liver revealed differential expression, notably of immune‐related genes, in mice of the congenic versus mixed background. In conclusion, our findings suggest that CFTR deficiency causes abnormal intestinal permeability, which, combined with diet‐induced dysbiosis and immune‐related genetic susceptibility, promotes CF‐related cholangiopathy.
The Myofibroblastic Conversion of Peribiliary Fibrogenic Cells Distinct from Hepatic Stellate Cells Is Stimulated by Platelet-Derived Growth Factor During Liver Fibrogenesis
The origin of myofibroblasts and the factors promoting their differentiation during liver fibrogenesis remain uncertain. During biliary-type fibrogenesis, the proliferation and chemoattraction of hepatic stellate cells (HSC) toward bile ducts is mediated by platelet-derived growth factor (PDGF), while myofibroblastic conversion of peribiliary cells distinct from HSC also occurs. We herein examined the phenotype of these peribiliary myofibroblasts as compared with myofibroblastic HSC and tested whether their differentiation was affected by PDGF. Biliary-type liver fibrogenesis was induced by common bile duct ligation in rats. After 48 hours, periductular fibrosis in portal tracts colocalized with smooth muscle α-actin–immunoreactive myofibroblasts, the majority of which were desmin negative. Simultaneously, in sinusoids, desmin immunoreactivity was induced in a large number of HSC, which were smooth muscle α-actin negative. Cultures of peribiliary myofibroblasts were expanded from isolated bile duct segments and compared with myofibroblastic HSC. Peribiliary myofibroblasts outgrowing from bile duct segments expressed smooth muscle α-actin, α1 (I) collagen mRNA, and PDGF receptor-β subunit. Desmin immunoreactivity gradually decreased in cultured peribiliary myofibroblasts, contrasting with constant labeling of all myofibroblastic HSC. In addition, IL-6 expression in peribiliary myofibroblasts was up to 100-fold lower than in myofibroblastic HSC, whereas the expression of the complement-activating protease P100 in both cell types showed little difference and that of the extracellular matrix component fibulin 2 was similar. The expression of smooth muscle α-actin protein in cultured peribiliary myofibroblasts was stimulated by PDGF-BB and inhibited by STI571, a PDGF receptor tyrosine kinase inhibitor, whereas in bile duct–ligated rats, the administration of STI571 caused a significant decrease in peribiliary smooth muscle α-actin immunoreactivity, and to a lesser extent, a decrease in peribiliary fibrosis. These results indicate that peribiliary cells distinct from HSC undergo a PDGF-mediated conversion into myofibroblasts expressing IL-6 at lower levels than myofibroblastic HSC and contribute to the initial formation of biliary-type liver fibrosis.
Hepatocellular Hypoxia-Induced Vascular Endothelial Growth Factor Expression and Angiogenesis in Experimental Biliary Cirrhosis
We tested the potential role of vascular endothelial growth factor (VEGF) and of fibroblast growth factor-2 (FGF-2) in the angiogenesis associated with experimental liver fibrogenesis induced by common bile duct ligation in Sprague-Dawley rats. In normal rats, VEGF and FGF-2 immunoreactivities were restricted to less than 3% of hepatocytes. One week after bile duct ligation, hypoxia was demonstrated by the immunodetection of pimonidazole adducts unevenly distributed throughout the lobule. After 2 weeks, hypoxia and VEGF expression were detected in >95% of hepatocytes and coexisted with an increase in periportal vascular endothelial cell proliferation, as ascertained by Ki67 immunolabeling. Subsequently, at 3 weeks the density of von Willebrand-labeled vascular section in fibrotic areas significantly increased. Semiquantitative reverse transcription polymerase chain reaction showed that VEGF 120 and VEGF 164 transcripts, that correspond to secreted isoforms, increased within 2 weeks, while VEGF 188 transcripts remained unchanged. FGF-2 mainly consisting of a 22-kd isoform, according to Western blot, was identified by immunohistochemistry in 49% and 100% of hepatocytes at 3 and 7 weeks, respectively. Our data provide evidence that in biliary-type liver fibrogenesis, angiogenesis is stimulated primarily by VEGF in response to hepatocellular hypoxia while FGF-2 likely contributes to the maintenance of angiogenesis at later stages.
Unexplained Chronically Elevated Aminotransferases: Liver Biopsy Gives Major Information with Therapeutic Implication in One Patient Out of Seven
Background & Aims Liver biopsy contribution in patients with unexplained elevation of transaminases is not clearly established. The aim was to study liver biopsy contribution in patients with unexplained elevated transaminases strictly defined according to the current guidelines, reflecting the present clinical practice. Methods In a retrospective study, we identified all the liver biopsies performed in patients with elevated transaminases for at least six months. Patients with a particular context, or with an identified cause of liver disease were excluded. The biopsies were classified according to the 4 following injury patterns: hepatitic, biliary, steatotic, vascular. Results 87 patients were included. Liver biopsy showed minimal changes or a normal histology in 48%, a steatotic pattern in 21%, a hepatitic pattern in 13%, a vascular pattern in 8%, a biliary pattern in 1%, and a mixed pattern in 8%. A cause could be determined in 21% of patients with normal histology, 85% with steatosis, 56% with hepatitis, 75% with biliary, but in none with isolated vascular pattern. Liver biopsy had important clinical and therapeutic implications in 15% of patients, with a diagnosis of autoimmune hepatitis, primary biliary cholangitis or metabolic dysfunction-associated steatohepatitis. Elevation of transaminases > 10 upper normal limit was present in all the patients with confirmed autoimmune hepatitis, but in only 7% of others. Conclusion Liver biopsy had important clinical and therapeutic implications in 15% of patients. However, the majority of patients had minimal changes without a cause, or minor vascular lesions of uncertain significance.
PDGF-Mediated Chemoattraction of Hepatic Stellate Cells by Bile Duct Segments in Cholestatic Liver Injury
The accumulation of myofibroblasts and fibrosis around proliferating bile ducts in cholestatic liver disease has been attributed to the proliferation and phenotypic modulation of portal fibroblasts, whereas the contribution of hepatic stellate cells remains uncertain. There is increasing evidence to indicate that bile ducts may stimulate chemoattraction of hepatic stellate cells (HSC). In the present study, we undertook dynamic tests to examine such a possibility and to investigate the role of two potential mediators: platelet-derived growth factor-BB (PDGF-BB) and endothelin-1. Cholestasis was induced by bile duct ligation in rats. HSC were isolated from normal rats and culture activated into myofibroblasts expressing PDGF-β receptors. Migration of myofibroblastic HSC was investigated in a Transwell chemotaxis filter assay. As compared with basal conditions, PDGF-BB (100 μg/l) and endothelin-1 (10−8m) induced a 3-fold and 1.7-fold increase in HSC migration, respectively. Bile duct segments isolated from cholestatic rats triggered a 3-fold increase in migration. This stimulation was significantly more potent than that observed in the presence of normal bile ducts. It was inhibited by neutralizing anti-PDGF antibodies and by STI571 PDGF receptor tyrosine kinase inhibitor, by 60% and 85%, respectively, whereas Bosentan, an endothelin receptor antagonist, had no significant inhibiting effect. In bile duct segments from cholestatic rats PDGF-B chain mRNA was detected at higher levels than in controls, whereas PDGF-BB was immunolocalized in bile duct epithelial cells. The results indicate that chemotaxis of HSC towards bile duct structures may contribute to the development of periductular fibrosis in cholestatic disorders, and that PDGF-BB is the major mediator in this process. In addition, anti-liver fibrogenic properties of STI571 are suggested by potent inhibition of myofibroblastic HSC function.
Non-contrast MR lymphography of the lymphatic system of the liver
This review shows the images obtained with non-contrast MR lymphography in different pathologic conditions affecting the liver. Non-contrast MR lymphography is obtained with a free-breathing 3D high spatial resolution fast-recovery fast spin-echo sequence similar to that used for 3D MR cholangiopancreatography. The liver is the largest lymph-producing organ generating approximately half of the body’s lymphatic fluid and is the most important part of the lymphatic system from a functional point of view. Therefore, understanding the anatomy, physiology, and physiopathology of the lymphatics of the liver is important. However, its anatomy and pathology are relatively unknown because of the absence of commonly used imaging techniques. We describe the anatomy, the physiology, and the pathophysiology of the lymphatic system of the liver and the possibility of identifying dilated lymphatic vessels in various liver diseases and conditions. Disruption of normal lymphatic structure and function is observed in various disease conditions. Liver lymph flow is directly correlated with portal venous pressure. Therefore, a dilatation of liver lymphatics is observed in portal hypertension as well as in increased pressure in hepatic veins. After liver transplantation, ligation of lymphatic vessels at the hilum reduces chylous ascites and results in lymphatic dilatation which is easily observed. In severe long-standing biliary stenosis, dilated lymphatic vessels are commonly demonstrated with non-contrast MR lymphography. In hepatocellular carcinoma, intrahepatic cholangiocarcinoma, and some metastases, lymphatic vessels are abundant in the immediate vicinity of the tumour. These various lymphatic abnormalities can be demonstrated with non-contrast MR lymphography.Key Points• Anatomy and pathology of the lymphatics of the liver are relatively unknown, partly because of lack of current imaging technique.• Non-contrast MR lymphography is obtained with a free-breathing 3D high spatial resolution fast spin-echo sequence similar to that used for 3D MR cholangiopancreatography.• Non-contrast MR lymphography may participate to the understanding of several abnormal liver conditions including portal hypertension, biliary diseases, and malignant hepatic tumours.