Morphometric analysis of dysplastic nodules in hepatitis C virus-related liver cirrhosis: comparison with cirrhotic and large regenerative nodules.

OBJECTIVE: To apply a computerized morphometric model to evaluate and quantify the morphologic features, including hepatic progenitor cells, in large regenerative nodules (LRN) and high grade dysplastic nodules (DN) in hepatitis C virus (HCV)-related cirrhosis. STUDY DESIGN: Thirty-two cirrhotic nodules; 10 LRN; and 8 DN were identified in cirrhotic livers with HCV-related cirrhosis removed at transplantation. All specimens were stained for routine diagnosis with hematoxylin-eosin and immunohistochemically for CD31, CD34, cytokeratin 7 (CK7) and reticulin. We determined by a computerized morphometric model on hematoxylin-eosin slices the volume fractions occupied by hepatocyte nuclei and cytoplasm, sinusoids, portal triads, fibrosis and centrilobular veins. We also investigated volume fraction of hepatocytes expressing CK7, and volume fractions of capillary units and of sinusoid capillarization expressing CD31 and CD34, respectively, and surface fraction of reticulin. RESULTS: Compared to LRN, DN showed higher volume fraction of hepatocyte nuclei, higher number of hepatocytes in unit volume, higher nuclear/cytoplasmic ratio, higher volume fractions of capillarized sinusoids, capillary units and CK7 positive hepatocytes and lower mean hepatocyte volume and surface reticulin fraction. CONCLUSION: Our morphometric model is an objective method of quantification of the morphologic changes of LRN and DN, including the hepatic progenitor compartment.

Molecular characterization of post-transplant lymphoproliferative disorders of donor origin occurring in liver transplant recipients.

Post-transplant lymphoproliferative disorders (PTLDs) represent a frequent complication of solid organ transplantation. Although most PTLDs arise from recipient lymphoid cells, a considerable fraction of cases may arise from donor B-cells. In an attempt to clarify the histogenesis and pathogenesis of PTLDs derived from donor B-cells, monoclonal PTLDs occurring in liver transplant recipients were chosen as a model to compare donor (D-PTLDs) versus recipient PTLDs (R-PTLDs). The tumour panel included nine D-PTLDs and six R-PTLDs. D-PTLDs were early-onset, EBV-infected lymphoproliferations classified as polymorphic PTLD (P-PTLD; n = 7) or diffuse large B-cell lymphoma (DLBCL; n = 2) with tumour localization confined to the hepatic hilum. All R-PTLDs were late-onset DLBCLs and showed extrahepatic localization. A BCL-6(-)/MUM1(+)/CD138(+/-) phenotype, consistent with a post-germinal centre (GC) stage of pre-terminal B-cell differentiation, was observed in all D-PTLDs and in 2/6 R-PTLDs, whereas a BCL6(+)/MUM1(-)/CD138(-) profile, reminiscent of GC B-cells, was detected in 4/6 R-PTLDs. The presence of somatic IGHV hypermutation was observed in 6/9 D-PTLDs and in 4/6 R-PTLDs, suggesting derivation from antigen-experienced B-cells. IGHV4-39 was the IGHV gene most frequently encountered, being rearranged in 3/9 D-PTLDs. Among IGHV-mutated PTLDs, a mutational profile suggesting antigen stimulation and/or selection was observed in 4/6 D-s and in 2/4 R-PTLDs. The presence of ongoing IGHV mutations was detected in 2/4 D-PTLDs. Aberrant SHM was detected in 10/15 (66.7%) PTLDs, including 6/9 D-PTLDs and 4/6 R-PTLDs. Our findings suggest that (i) D-PTLDs show a clinical presentation distinct from R-PTLDs; (ii) immunophenotypic and genetic features of D-PTLDs are consistent with mature, GC-experienced B-cells; (iii) transformed donor-derived B-cells may experience antigen-driven stimulation and selection, and may acquire genetic lesions during neoplastic expansion in the recipient environment; and (iv) EBV infection and expression of viral oncoproteins may be relevant in the pathogenesis of D-PTLDs.

Killer cell immunoglobulin-like receptor genotype and killer cell immunoglobulin-like receptor-human leukocyte antigen C ligand compatibility affect the severity of hepatitis C virus recurrence after liver transplantation.

In 20% to 30% of infected individuals, hepatitis C virus (HCV) can cause cirrhosis and hepatocellular carcinoma, for which liver transplantation is the best treatment available. HCV re-infection is universal, and hepatitis disease recurrence occurs in most cases with a 30% probability of progression to graft cirrhosis at 5 years post-transplant. The immunological response to HCV involves natural killer (NK) cells and killer cell immunoglobulin-like receptors (KIRs), which specifically recognize human leukocyte antigen (HLA) class I antigens present on target cells. The effector functions of NK cells are influenced by inhibitory KIR interaction with self-HLA class I ligands, with HLA-C being the most predominant. This study examines the roles of KIR genotypes and their HLA ligands in both HCV disease recurrence and its progression. A total of 151 patients were included in the cohort, and their clinical details were recorded. Liver biopsies were used to define the absence/presence of recurrent hepatitis, the degree of fibrosis, and the progression to cirrhosis over a 10-year period. Mismatching of KIR-HLA-C ligands between donor-recipient pairs was associated with the recurrence of hepatitis (P = 0.008). The presence of KIR2DL3 in the recipient correlated with progression to liver fibrosis (P = 0.04). The mismatching of HLA-KIR ligands favored the progression of the recurrent hepatitis to fibrosis only in the presence of KIR2DL3 (P = 0.04). These preliminary results indicate that the KIR genotype and KIR-HLA-C ligand compatibility play roles in the recurrence and progression of hepatitis C disease in liver transplant recipients.

Gene expression, cytoskeletal changes and extracellular matrix synthesis in human osteoblasts treated with cyclosporin A.

Cyclosporin A (CyA) is an immunosuppressive agent used to prevent allograft rejection, but unfortunately it causes adverse effects such as bone diseases, osteoporosis and osteomalacia. These pathologies involve an imbalance between synthesis, degradation and mineralization of extracellular matrix. CyA can modify extracellular matrix components such as glycosaminoglycans (GAG) and collagen fibers. In addition, normal cell activity is dependent on cell morphology and substrate cell attachment. We treated normal human osteoblasts with CyA and analyzed: (i) gene expression by a microarray method; (ii) extracellular GAG and collagen after (3)H-glucosamine and Western blot analysis; and (iii) cytoskeletal changes, using actin and tubulin fluorescent antibodies. CyA increased intra- and extracellular GAG and extracellular GAG classes such as hyaluronic acid, chondroitin sulphate, and dermatan sulphate; there was no noteworthy effect on heparan sulphate and the ratio of non-sulphated to sulphated GAG. In osteoblast cultures the drug reduced cytoskeletal actin, while tubulin did not change. In vivo the osteoblasts showed morphological changes with different extracellular matrix synthesis. Microarray analysis indicated the inhibition of gene pathways related to Wnt signaling molecules, and the cytoskeletal and focal adhesion cascade. In in vitro human osteoblasts CyA modified gene expression related to cytoskeletal pattern organization and cell morphology. Since in bone pathologies osteoblasts show different morphology related to cell size, these data suggest that in vivo osteoblast different functions could be dependent on alteration of osteoblast differentiation.

Role of MDCT in the diagnosis of hepatocellular carcinoma in patients with cirrhosis undergoing orthotopic liver transplantation.

OBJECTIVE: The purpose of this study was to assess the diagnostic performance of MDCT in the detection of hepatocellular carcinoma in patients with cirrhosis undergoing orthotopic liver transplantation. MATERIALS AND METHODS: Eighty-eight consecutively registered patients who underwent MDCT 6 months before liver transplantation were evaluated. The original reports were analyzed, and the CT images were retrospectively reevaluated independently by two radiologists who made the final interpretation in consensus. The imaging findings were correlated with histopathologic findings in the explanted livers on a patient-by-patient and a lesion-by-lesion basis. RESULTS: Histopathologic examination revealed 139 hepatocellular carcinomas in 48 of the 88 patients. MDCT correctly depicted 89 of 139 hepatocellular carcinomas (sensitivity, 64%) at the original examination and 102 at reevaluation (sensitivity, 73.3%). Patient-by-patient analysis showed a specificity of 75% in the original reports and of 77.5% at reevaluation. A large number of false-positive nodules were found, most (59.2%) of them being smaller than 1 cm in diameter. CONCLUSION: MDCT has reasonable sensitivity in the detection of hepatocellular carcinoma in patients with cirrhosis who undergo liver transplantation. Attention should be paid, however, to avoiding overestimation of the extent of disease.

Glycosaminoglycan, collagen, and glycosidase changes in human osteoblasts treated with interleukin 1, and osteodystrophy.

Normal bone homeostasis involves a balance between osteoblast and osteoclast action, regulated by hormones and cytokine stimuli. Hemodialysis patients appear to have increased production of interleukin-1 (IL-1), interleukin-6 (IL-6) and glycosaminoglycans (GAG) in serum. IL-1 plays a role in the synthesis, degradation and degree of sulphatation of ECM components such as glycosaminoglycans. Also, continuous changes in the ECM involve enzymes such as beta-N-acetyl-d-glucosaminidase (beta-NAG) and beta-d-glucuronidase (beta-GLU) which act on different GAG classes and collagen fibers. We examined the effects of IL-1alpha on ECM synthesis and the related enzymes in human uremic osteoblast cultures. We also measured the levels of IL-1beta, and IL-6 and alkaline phosphatase activity. In biopsies of uremic bone there was less ECM deposition than resorption associated with changes in osteoblast morphology. In vitro osteoblast proliferation was higher (P< or =0.01), and extracellular GAG lower (P< or =0.01) than in controls. The enzyme beta-NAG was high (P< or =0.05) but there were no noteworthy changes in beta-GLU. ELISA of the medium indicated spontaneous production of IL-1beta and IL-6, which significantly increased after IL-1alpha treatment compared to controls. IL-1alpha reduced alkaline phosphatase activity (P< or =0.01) in uremic osteoblast cultures. IL-1 acts on osteoblasts with decreases in GAG synthesis and alkaline phosphatase activity, while beta-NAG increases. This lead to a reduction in the organic component in ECM and its mineralization, and to changes in the regulation of cytokine activity by GAG. The enzymatic breakdown might be facilitated by metabolic acidosis and failed osteoblast differentiation; these factors could be correlated with different degrees of osteodystrophy.

Liver transplantation for HCV cirrhosis: improved survival in recent years and increased severity of recurrent disease in female recipients: results of a long term retrospective study.

In recent years, a worsening outcome of hepatitis C virus (HCV)-positive recipients and a faster progression of recurrent disease to overt cirrhosis has been reported. Our aims were to 1) assess patient survival and development of severe recurrent disease (Ishak fibrosis score > 3) in different transplant years; and 2) model the effects of pre- and post-liver transplantation (LT) variables on the severity of recurrent disease. A multicenter retrospective analysis was conducted on 502 consecutive HCV-positive transplant recipients between January 1990 and December 2002. Protocol liver biopsies were obtained at 1, 3, 5, 7, and 10 yr post-LT in almost 90% of the patients. All 502 patients were included in the overall survival analysis, while only the 354 patients with a follow-up longer than 1 yr were considered for the analysis of predictors of disease progression. The overall Kaplan-Meier survival rates were 78.7%, 66.3%, and 58.6%, at 12, 60, and 120 months, respectively, and a trend for a better patient survival over the years emerged from all 3 centers. The cumulative probability of developing HCV-related recurrent severe fibrosis (Ishak score 4-6) in the cohort of 354 patients who survived at least 1 yr remained unchanged over the years. Multivariate analysis indicated that older donors (P = 0.0001) and female gender of recipient (P = 0.02) were the 2 major risk factors for the development of severe recurrent disease, while the adoption of antilymphocytic preparations was associated with a less aggressive course (P = 0.03). Two of these prognostic factors, donor age and recipient gender, are easily available before LT and their combination showed an important synergy, such that a female recipient not only had a much higher probability of severe recurrent disease than a male recipient but her risk increased with the increasing age of the donor, reaching almost 100% when the age of the donor was 60 or older. In conclusion, a trend for a better patient survival was observed in more recent years but the cumulative probability of developing severe recurrent disease remained unchanged. The combination of a female recipient receiving an older graft emerged as a strong risk factor for a severe recurrence.

Cryoglobulinemia.

Cryoglobulinemia refers to the presence in serum of immunoglobulins that precipitate at a cold temperature. Type I cryoglobulins are single monoclonal immunoglobulins usually associated with haematological disorders. Types II and III are mixed cryoglobulins, composed of monoclonal or polyclonal IgM respectively, having rheumatoid factor activity that bind to polyclonal immunoglobulins. Mixed cryoglobulinemia (MC) syndrome is a consequence of immune-complex mediated vasculitis and is characterized by a typical clinical triad: purpura, weakness, arthralgias; many organs particularly kidney and peripheral nervous system may be involved. MC may be associated with infectious and systemic disorders and since 1990 studies have demonstrated that hepatitis C virus (HCV) may be considered the principal trigger of the disease. The relation between MC and HCV infection shows new insights in the interpretation of the link between viral infection, autoimmune phenomena and lymphoproliferative disorders evolution. In fact, the virus chronically stimulates B-cell polyclonal proliferation from which a monoclonal population may emerge. In symptomatic patients with HCV related MC therapeutic strategy should include an attempt at viral eradication. Antiviral therapy may also be effective in determining the regression of B-cell lymphoproliferative disorder. Rituximab could represent a safe and effective alternative to standard immunosuppression and exerts selective B-cell control.

De novo cancers and post-transplant lymphoproliferative disorder in adult liver transplantation.

De novo cancer is one of the most serious complications after organ transplantation. Chronic immunosuppression, viral agents, pretransplant chronic alcohol-induced and other addictive behavior-induced injury are important conditions associated with the development of de novo cancers in solid organ transplants. The aim of the study was to evaluate types and clinical course of de novo cancers in adult liver transplant recipients. Data regarding 502 adult patients who underwent to 554 liver transplantations have been collected. Sex, age at transplantation, immunosuppressive regimen, time from transplantation to diagnosis of cancer, cancer type, surgical and non-surgical treatments and follow-up time have been analyzed as well as acute rejection episodes and viral status. Thirty patients developed 31 de novo cancers. The predominant tumors were carcinoma of the skin, lymphomas and Kaposi's sarcoma. Kaposi's sarcoma and lung cancer were associated with greater mortality. In lymphomas and Kaposi's sarcoma, a high rate of graft involvement was observed. In liver transplant recipients, de novo cancers demand strategies focusing on prophylactic and careful long-term screening protocols. Lymphomas and Kaposi's sarcoma should be ruled out in all patients with clinical manifestations of chronic biliary obstruction.

Insulin resistance is associated with steatosis in nondiabetic patients with genotype 1 chronic hepatitis C.

Conflicting data exist regarding the relationship between hepatitis C virus genotype 1 and hepatic steatosis as well as the latter's role in the progression of fibrosis and treatment response. We assessed factors associated with hepatic steatosis in genotype 1 chronic hepatitis C and the impact of hepatic fat on fibrosis development and interferon responsiveness. Two hundred ninety-one non-diabetic patients with genotype 1 chronic hepatitis C were examined for the presence of steatosis and its correlation with clinical, virological, and biochemical data, including insulin resistance (IR), evaluated by the homeostasis model assessment (HOMA) score. Steatosis was graded as mild (1%-20% of hepatocytes involved), moderate (21%-40% of hepatocytes involved), and severe (>40% of hepatocytes involved). Steatosis was mild in 110 of 291 (37.8%) and moderate/severe in 55 of 291 (18.9%) subjects. By logistic regression, moderate/severe steatosis was independently associated with the female sex (odds ratio [OR] 2.74; 95% CI 1.40-5.35), high gamma-glutamyltransferase levels (OR 1.52; 95% CI 1.22-1.91), and HOMA-score (OR 1.076; 95% CI 1.001-1.26). By logistic regression, moderate/severe steatosis (OR 2.78; 95% CI 1.21-6.4), and platelet counts (OR 0.97; 95% CI 0.96-0.98) were independent predictors of advanced fibrosis. Patients with moderate/severe steatosis had an OR of 0.52 (95% CI 0.30-0.90) for sustained virological response compared with patients with mild/absent steatosis. In conclusion, in nondiabetic European patients with genotype 1 hepatitis C at low risk for the metabolic syndrome, the prevalence of steatosis was nearly 60%. IR is a risk factor for moderate/severe steatosis, especially in men. Moderate/severe steatosis has clinical relevance, being associated with advanced fibrosis and hyporesponsiveness to antiviral therapy.

Predictors of long-term survival after liver transplantation for hepatocellular carcinoma.

AIMS: The aim of this study was to identify predictors of both survival and tumor-free survival of a cohort of 155 patients, with hepatocellular carcinoma (HCC) and cirrhosis, who were treated by orthotopic liver transplantation (OLT). METHODS: From January 1989 to December 2002, 603 OLTs were performed in 549 patients. HCC was diagnosed in 116 patients before OLT and in 39 at histological examination of the explanted livers. Eighty-four percent of the patients met "Milan" criteria at histology. Ninety-four patients received anticancer therapies preoperatively. RESULTS: The median follow-up was 49 months (range, 0-178). Overall, 1-, 3-, 5-, and 10-yr survival were 84%, 75%, 72%, and 62%, respectively. Survival was not affected by the patient's age or sex, etiology of liver disease, Child score at transplantation, rejection episodes, tumor number, total tumor burden, bilobar tumor, and pathologic Tumor, Nodes, Metastasis (pTNM) stages. There was no statistically significant difference in survival when patients were grouped according to the recently proposed simplified pTNM staging (5-yr survival, 80% in stage I, 69% in stage II, 50% in stage III, p= 0.3) or the United Network for Organ Sharing (UNOS) staging system for HCC. Encapsulation of the tumor and alpha-fetoprotein levels significantly affect patient survival. Five-year survival of patients with poorly differentiated (G3) HCC was significantly worse than that of patients with moderately (G2) or well-differentiated (G1) HCC (respectively, G3 44%, G2 67%, and G1 97%, p= 0.0015). Patients with micro- or macro-vascular invasion had a worse 5-yr survival than patients without vascular invasion (49%vs 77%, p= 0.04). Multivariate analysis showed that histological grade of differentiation and macroscopic vascular invasion are independent predictors of survival (HR 2.4, 95% CI 1.4-4.1, p= 0.0009 and HR 2.8, 95% CI 1.2-6.8, p= 0.022). CONCLUSION: Histological grade of differentiation and macroscopic vascular invasion, as assessed on the explanted livers, are strong predictors of both survival and tumor recurrence in patients with cirrhosis who received transplants for HCC.

Computerized morphometry of the cirrhotic liver: comparative analysis in primary biliary cirrhosis, alcoholic cirrhosis, and posthepatitic cirrhosis.

Fibrosis and nodular regeneration are the hallmarks of liver cirrhosis. To assess the degree of fibrosis and the severity of the structural changes affecting parenchymal and extraparenchymal components in liver cirrhosis, a computerized morphometric model has been applied to liver specimens from patients undergoing liver transplantation for primary biliary cirrhosis, posthepatitic and alcoholic cirrhosis. Fifty-eight hepatectomy specimens from patients undergoing liver transplantation for cirrhosis were analyzed: 17 alcoholic, 28 posthepatitic (HBV-related and HCV-related cirrhosis), and 13 primary biliary cirrhoses. Liver specimens were fixed in 10% neutral-buffered formalin and embedded in paraffin. Sections were stained with chromotrope-aniline blue method and monoclonal antibodies against cytokeratin 7 and CD31. Volume fractions of parenchymal compartment and fibrosis were stereologically determined on the specimens stained with chromotrope-aniline blue method. Volume fractions of portal bile ducts, proliferated bile ductules, and hepatocytes with biliary metaplasia were measured on cytokeratin 7 stains, while volume fractions of capillary units have been evaluated on CD31 staining. Volume fraction of fibrosis was higher in primary biliary cirrhosis than in the other disease-induced cirrhosis. The main differences were related to immunohistochemical staining. Volume fraction of hepatocytes with biliary metaplasia was higher in HCV-related cirrhosis, whereas volume fractions of biliary structures were more prominent in HBV-related cirrhosis. Primary biliary cirrhosis was characterized by a reduced number of bile ducts and by a wider expression of cytokeratin 7 into periportal hepatocytes. Capillary units were more prominent in primary biliary cirrhosis than alcoholic and posthepatitic cirrhosis. Our computerized morphometric model well describes and quantifies the morphological alterations of the liver and it could represent an adjunctive tool to evaluate the degree of dysplastic phenomena involving parenchymal and extraparenchymal compartments.

Aggressive systemic mastocytosis mimicking sclerosing cholangitis.

A 43 year-old woman presented with fever, abdominal pain, epato-splenomegaly, ascites, cholestasis, anemia, thrombocytopenia and previous diagnosis of sclerosing cholangitis based on liver biopsy and endoscopic retrograde cholangiopancreatography(ERCP). The bone marrow biopsy and the revision of liver biopsy using antitryptase stain diagnosed systemic mastocytosis. Because of the aggressive course of the disease the patient was treated with an acute myeloid leukaemia chemotherapy regimen without success.

Analysis of histological and immunohistochemical patterns of the liver in posthepatitic and alcoholic cirrhosis by computerized morphometry.

To assess the degree of fibrosis and the structural changes affecting parenchymal and extraparenchymal components in liver cirrhosis, a computerized morphometric model has been applied to liver specimens from patients with posthepatitic and alcoholic cirrhosis. All specimens have been stained with chromotrope-aniline blue method and monoclonal antibodies against cytokeratin 7, CD31, and VIII factor. Volume fractions of parenchymal compartment and fibrosis have been determined stereologically on CAB slices; moreover, volume fractions of portal bile ducts and proliferated bile ductules, hepatocytes with biliary metaplasia, capillary units, and vascular structures have been measured. Volume fraction of fibrosis was higher in alcoholic cirrhosis when compared with the case of posthepatitic cirrhosis. Volume fractions describing parenchymal compartment showed a similar trend in both viral groups. The main differences were related to immunohistochemical stainings. Volume fraction of hepatocytes with biliary metaplasia was higher in hepatitis C virus-related cirrhosis, whereas volume fractions of biliary structures were more prominent in hepatitis B virus-related cirrhosis. Capillary units were more prominent in posthepatitic cirrhosis than in alcoholic cirrhosis. Interestingly, both forms of posthepatitic cirrhosis show similar features when compared with alcoholic cirrhosis. Our computerized morphometric model well describes and quantifies the morphological alterations of the liver, and it could represent an adjunctive tool to evaluate the degree of dysplastic phenomena involving parenchymal and extraparenchymal components.

Chromosomal alterations in hepatocellular nodules by comparative genomic hybridization: high-grade dysplastic nodules represent early stages of hepatocellular carcinoma.

Data from experimental hepatocarcinogenesis and recent studies in humans have suggested that the emergence of hepatocellular carcinoma (HCC) is a stepwise process. However, despite abundant experimental data, the precise molecular mechanisms and genetic alterations involved in human liver carcinogenesis are still unclear. Comparative genomic hybridization was used to analyze 26 hepatocellular nodules obtained from patients undergoing liver transplantation or surgical resection for HCC. According to the criteria proposed by the International Working Party, 16 nodules were classified as multiacinar regenerative nodules (MRN), 4 as low-grade dysplastic nodules (LG-DN), and 6 as high-grade dysplastic nodules (HG-DN). Our aim was to investigate the possible genetic differences between MRN, LG-DN, and HG-DN. The whole group of nodules showed only a few aberrations (mean 1.1/case), without any significant pattern. This finding is comparable to what happens in non-neoplastic tissue. On the contrary, in three of six HG-DN, we found deletions of 8p and gains of 1q. LG-DN and MRN did not show these chromosomal imbalances. These results confirm the important role of allelic losses on 8p as well as of gains of 1q in HCC. We conclude that the genes that are important in early stages of hepatocarcinogenesis are probably located on these chromosomal arms.