Viral elimination reduces incidence of malignant lymphoma in patients with hepatitis C

Recent advances in managing chronic HCV infection: focus on therapy in patients with severe liver disease

Chronic hepatitis C virus (HCV) infection still represents a major public health problem, as it is thought to be responsible for more than 350,000 deaths around the globe on a yearly basis. Fortunately, successful eradication of the virus has been associated with improved clinical outcome and reduced mortality rates. In the past few years, treatment has improved considerably by the implementation of direct-acting antivirals (DAAs). From 2014 onwards, sofosbuvir, simeprevir, daclatasvir, ledipasvir, paritaprevir, ombitasvir, and dasabuvir have been approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA). Regimens with various combinations of these new drugs, without the use of interferon (IFN), proved to be very effective and well tolerated, even among patients with advanced liver disease. Moreover, treatment duration could be shortened to 12 weeks in the majority of patients. The high costs of these DAAs, however, limit the availability of IFN-free therapy worldwide. Even in wealthy countries, it is deemed necessary to prioritize DAA treatment in order to limit the immediate impact on the health budget. As patients with advanced liver disease are in most need of HCV clearance, many countries decided to treat those patients first. In the current review, we focus on the currently available IFN-free treatment options for patients with cirrhosis. We discuss the virological efficacy as well as the clinical relevance of these regimens among this specific patient population.

The expanding spectrum of HCV-related cryoglobulinemic vasculitis: a narrative review

Cryoglobulinemic vasculitis (CV) is a small-to-medium-vessel vasculitis that appears in 10-15 % of patients chronically infected with hepatitis C virus (HCV). The classic symptom triad of CV, purpura/asthenia/arthralgia, is accompanied by clinical features that include glomerulonephritis, neuropathy, interstitial pneumonitis, and cardiomyopathy, ranging in their severity from mild to life threatening. The risk of developing non-Hodgkin lymphoma is also higher. The cumulative 10-year survival rate of CV patients is significantly lower than in the age- and sex-matched general population, with death typically caused by nephropathy, malignancies, liver involvement, and severe infections. Unfailing serological stigmata include both a cryoglobulin IgM fraction with rheumatoid factor activity and decreased complement C4 levels. On peripheral B cells, the expression of the CD81 B cell receptor is reduced while that of the CD19 receptor is increased. A monoclonal B cell lymphocytosis develops in almost one-third of patients. HCV-related proteins (but not HCV-RNA genomic sequences) can be detected on biopsy samples by immunofluorescence and immunohistochemistry and involve the vessel lumen, vessel walls, and the perivascular spaces of the skin, kidney, and peripheral nerves, supporting the pathogenetic role of HCV in the onset of a widespread microvasculitis. Based on the demonstration of HCV infection in the large majority of CV patients, a therapeutic regimen consisting of once-weekly pegylated interferon-α and the daily administration of ribavirin results in a sustained virologic response in ~50 % of patients. In those with refractory and relapsing disease, addition of the anti-CD20 monoclonal antibody rituximab has significantly increased the overall response rates. The extension to CV of latest-generation direct-acting antivirals, strikingly successful in non-CV HCV-positive patients, has yielded high complete response rates according to the few studies published thus far.

Hepatitis C viral infection increases the risk of lymphoid-neoplasms: A population-based cohort study

Chronic hepatitis C viral (HCV) infection has been associated with non-Hodgkin's lymphoma (NHL); however, the results are inconsistent among regions with different HCV prevalence rates. The temporal relationship, risk estimates, and association between HCV and lymphoid-neoplasms remain unclear. This study investigated the temporal relationship between HCV infection and lymphoid-neoplasms using a nationwide population-based cohort. Patients with chronic HCV infection were retrieved from the Taiwan National Health Insurance Research Database during 2001-2005 and designated as the HCV cohort. Those with prior malignancies or coinfected with hepatitis B or human immunodeficiency virus were excluded. The age, sex, and comorbidities, including rheumatological disorders and diabetes, were matched by propensity scores to another non-HCV cohort. Both cohorts were followed longitudinally until 2009 for a new diagnosis of any lymphoid-neoplasms or NHL. A total of 11,679 HCV and 46,716 non-HCV patients were included and followed for 8 years. The incidence rates of any lymphoid-neoplasms and NHL were significantly greater in the HCV cohort than the non-HCV cohort (48.4 versus 22.1, and 37.0 versus 17.5 per 100,000 person-years, respectively, both P < 0.001), even after we excluded lymphoid-neoplasms developed within the first year of follow-up. Cox proportional hazards regression analysis (after adjustment for age, sex, numbers of annual medical visits during follow-up, and comorbidities) indicated that HCV infection was associated with an increased risk of either any lymphoid-neoplasms (hazard ratio = 2.30, 95% confidence interval 1.55-3.43, P < 0.0001) or NHL (hazard ratio = 2.00, 95% confidence interval 1.27-3.16, P = 0.003).

CONCLUSION

After adjustment for confounders and biases, chronic HCV infection is temporally associated with a two-fold increased risk of lymphoid-neoplasms, especially NHL, in Asian patients; additional large studies are needed to explore whether HCV eradication can reduce the incidence of lymphoid-neoplasms.

Extrahepatic manifestations of chronic hepatitis C virus infection

During hepatitis C virus (HCV) chronic infection, extrahepatic manifestations are frequent and polymorphous. This article reports on a large cohort of patients with HCV-related autoimmune or lymphoproliferative disorders, from mixed cryoglobulinemia vasculitis to frank lymphomas. The relationship between HCV infection and such immune-related diseases has been formally demonstrated by epidemiological, clinical, immunological and pathological data, and results of therapeutic trials. More recently, other nonliver-related HCV disorders have been reported, including cardiovascular (i.e. stroke, ischemic heart disease), renal, metabolic and central nervous system diseases. For these manifestations, most evidence comes from large epidemiological studies; there is a need for mechanistic studies and therapeutic trials for confirmation. Beyond the risk of developing liver complications, that is, cirrhosis and liver cancer, patients with HCV infection have an increased risk of morbidity and mortality related to nonliver diseases. HCV chronic infection should be analyzed as a systemic disease in which extrahepatic consequences increase the weight of its pathological burden. The need for effective viral eradication measures is underlined.

The role of infectious agents, antibiotics, and antiviral therapy in the treatment of extranodal marginal zone lymphoma and other low-grade lymphomas

OPINION STATEMENT

There is strong evidence to corroborate the association with Helicobacter pylori (Hp) to gastric extranodal marginal zone lymphoma (ENMZL) and hepatitis C virus (HCV) to splenic/nodal marginal zone lymphoma. Koch's postulates generally hold for these two associations and eradication of the infectious agent is well supported. Hp eradication (HPE) is recommended as front-line therapy for early stage gastric ENMZL regardless of Hp status. Complete response (CR) rate for Hp-negative patients is not as high as for Hp-positive patients; however, the benign nature of HPE and high rates of salvage allow this strategy to be safe while sparing some Hp-negative patients from systemic therapy or radiation. Similarly for HCV-seropositive patients, treatment with antivirals should be strongly considered as first-line for those who do not require immediate cytoreductive therapy or at some point even after completing chemoimmunotherapy. The controversy regarding the role for antibiotics is greatest for primary ocular adnexal lymphoma (POAL). Considering the low incidence of Chlamydia psittaci (Cp) infection with OAL and the challenges to reliably identifying Cp, we typically do not consider doxycycline in POAL treatment. Involved-field radiotherapy (IFRT) remains the treatment of choice for most with unilateral POAL. However, if reliable detection of Cp is available and Cp is identified, patients with unilateral low tumor stage POAL who do not require immediate radiotherapy could be considered for doxycycline as front-line treatment. Other infectious associations to indolent lymphomas have been made, including Borrelia borgdorferi (Bb) in cutaneous lymphoma and Campylobacter in immunoproliferative small intestinal disease (IPSID), but these associations are not as strong and primary treatment targeting the infectious agents is not recommended.

Why do I treat my patients with mild hepatitis C?

The major advances achieved in the treatment of HCV by the development of new direct-acting antiviral agents (DAAs) allow treatment of almost the entire spectrum of patients with chornic infection. As a result of the exceedingly high cost of DAAs in many countries, IFN-free DAA regimens are mostly reserved to patients with advanced fibrosis or cirrhosis. Hence, treatment of patients with milder liver disease is often deferred. This could ultimately result in an increased burden of advanced liver disease and in increased long-term costs of management. Moreover, studies performed during the 'interferon era' and the early data on interferon-free regimens show that patients without severe fibrosis achieve higher rates of sustained virological response with less treatment-related adverse events. Unfortunately, there is no univocal way to predict the progression of liver fibrosis and therefore to identify the patients with early disease who would require urgent HCV treatment. Many studies have also demonstrated that treatment-induced HCV clearance reduces all-cause mortality regardless of the stage of liver fibrosis, pointing to an effect on extrahepatic manifestations of HCV infection. Last but not least, pharmacoeconomic studies show that DAA treatment of patients with mild HCV disease is cost-effective even at high prices of drugs, thus suggesting the opprtunity to treat regardless of the stage of liver disease.

Hepatitis C virus-associated B-cell non-Hodgkin's lymphomas: what do we know?

Epidemiological studies have shown an increased risk of developing B-cell lymphomas in patients with chronic hepatitis C virus (HCV) infection. There is, however, a great geographic variability and it remains unclear whether additional environmental and genetic factors are involved or whether the international discrepancies represent simply a consequence of the variable prevalence of HCV infection in different countries. Other confounding factors may affect the comparability of the different studies, including the method of HCV assessment, the selection of normal controls, the lymphoma classification used and the year of publication. The most convincing evidence for a causal relationship comes from the observation, mainly limited to some indolent subtypes, of B-cell lymphoma regressions after successful HCV eradication with antiviral treatment. Yet, the molecular mechanism of HCV-induced lymphomagenesis are mainly hypothetical. According to most plausible models, lymphoma growth is a consequence of continuous antigenic stimulation induced by the chronic viral infection. This review will summarize the current knowledge on HCV-associated lymphomas and their management.

Extrahepatic Manifestations of Hepatitis C Virus

Chronic infection with the hepatitis C virus (HCV) is a major cause of liver disease worldwide and is also responsible for extrahepatic manifestations (EHMs) involving the skin, kidneys, salivary glands, eyes, thyroid, and immune system. Mixed cryoglobulinemia is the prototype EHM related to HCV infection. Although these HCV-related EHMs may contribute to significant rates of morbidity affecting patient's quality of life and survival, most of these complications can reverse after HCV eradication by interferon therapy. This notwithstanding, individual patients may have an irreversible injury in various organs that is not reversed by a cure of the HCV infection.

Sustained virological response to antiviral therapy improves survival rate in patients with recurrent hepatitis C virus infection after liver transplantation

AIM

Previous European and North American studies analyzed the relationship between survival rate and sustained virological response (SVR) to interferon (IFN) therapy in patients with recurrent hepatitis C viral (HCV) infection after liver transplantation (LT). The present study was designed to define the same relationship in Japanese patients who had undergone LT.

METHODS

Forty-seven patients (genotype 1, 40; genotype 2, 7) with recurrent HCV after LT were treated with pegylated interferon (PEG IFN) or IFN/ribavirin (RBV). In possible, within 3 months after LT, patients started treatment with PEG IFN-α-2b or IFN-α-2b s.c. once weekly combined with RBV (200 mg/day).

RESULTS

The SVR rate was 51% (24/47) for all patients, 42.5% (17/40) for genotype 1 and 100% (7/7) for genotype 2. The median follow-up period was 71 months (range, 24-152). The survival rate of 24 patients who achieved SVR was 95% at 5 years and 92% at 10 years. These rates were significantly better than those of 23 patients who did not achieve SVR (82% at 5 years, 58% at 10 years) (P = 0.027). Two patients of the SVR group died during follow up (due to hepatocellular carcinoma in one and chronic rejection in one), while six non-SVR patients died during the same period (three died due to liver failure by recurrent HCV).

CONCLUSION

SVR following IFN therapy contributes to improvement of survival rate in patients with recurrent post-LT HCV infection.

Extrahepatic morbidity and mortality of chronic hepatitis C

Chronic hepatitis C virus (HCV) infection is associated with several extrahepatic manifestations. Patients with HCV may develop mixed cryoglobulinemia and its sequelae, ranging from cutaneous and visceral vasculitis to glomerulonephritis and B-cell non-Hodgkin lymphoma. HCV-infected patients have increased rates of insulin resistance, diabetes, and atherosclerosis, which may lead to increased cardiovascular morbidity and mortality. Neurological manifestations of HCV infection include fatigue and cognitive impairment. The mechanisms causing the extrahepatic effects of HCV infection are likely multifactorial and may include endocrine effects, HCV replication in extrahepatic cells, or a heightened immune reaction with systemic effects. Successful eradication of HCV with interferon alfa and ribavirin was shown to improve some of these extrahepatic effects; sustained virological response is associated with resolution of complications of cryoglobulinemia, reduced levels of insulin resistance, reduced incidence of diabetes and stroke, and improved fatigue and cognitive functioning. The availability of new interferon-free, well-tolerated anti-HCV treatment regimens is broadening the spectrum of patients available for therapy, including those in whom interferon was contraindicated, and will likely result in greater improvements in the extrahepatic manifestations of HCV. If these regimens are shown to confer significant benefit in the metabolic, cardiovascular, or neuropsychiatric conditions associated with HCV infection, extrahepatic manifestations of HCV may become a major indication for treatment even in the absence of liver disease.

HCV-associated B-cell non-Hodgkin lymphomas and new direct antiviral agents

BACKGROUND & AIMS

Hepatitis C virus-related B-cell proliferation is a model of virus-driven autoimmune/neoplastic disorder leading to mixed cryoglobulinaemia and/or B-cell non-Hodgkin lymphoma. These lymphomas are often marginal zone lymphomas or diffuse large B-cell lymphomas. Peginterferon/Ribavirin therapy has proved its crucial role in the cure of these non-Hodgkin lymphomas, but data are lacking concerning new direct anti-viral agents.

METHODS

We report five cases of Hepatitis C virus-associated B-cell non-Hodgkin lymphoma treated with direct anti-viral agents: two marginal zone lymphomas received direct anti-viral agents alone (one with a leukaemic phase only, one with splenic and deep lymph nodes localizations); one renal marginal zone lymphoma with renal insufficiency received direct anti-viral agents and four rituximab infusions simultaneously; two diffuse large B-cell lymphomas were treated with direct ant-viral agents following chemotherapy.

RESULTS

Sustained virological response was obtained in all patients, and complete remission of NHL was noted 6 months after cessation of any treatment except for one patient with a persistent small leukaemic phase.

CONCLUSION

Direct anti-viral agents might be proposed as a first-line treatment in marginal zone lymphomas in the case of no life-threatening complications with the precaution of a long-term follow-up. In the setting of diffuse large B-cell lymphomas, well-tolerated direct anti-viral agents could potentially be introduced very early not only to prevent relapse of these lymphomas but also to limit the liver toxicity of chemotherapy and rituximab by preventing outbreaks of viral load. New observations and trials should support these assumptions.

Virus-driven autoimmunity and lymphoproliferation: the example of HCV infection

HCV chronic infection is characterized by possible development of both hepatic and extrahepatic manifestations. The infection by this both hepatotropic and lymphotropic virus is responsible for polyoligoclonal B-lymphocyte expansion, leading to several immune-mediated disorders. Mixed cryoglobulinemia syndrome that in some cases may evolve to frank B-cell non-Hodgkin's lymphoma is the prototype of HCV-driven autoimmune and lymphoproliferative disorders. The HCV oncogenic potential has been suggested by several clinicoepidemiological and laboratory studies; it includes hepatocellular carcinoma, B-cell non-Hodgkin's lymphoma and papillary thyroid cancer. The definition HCV syndrome refers to the complex of HCV-driven diseases; these latter are characterized by heterogeneous geographical distribution, suggesting a role of other important genetic and/or environmental cofactors. The natural history of HCV syndrome is the result of a multifactorial and multistep pathogenetic process, which may evolve from mild manifestations to systemic autoimmune disorders, and less frequently to malignant neoplasias. The present updated review analyzes the clinical and pathogenetic aspects of the main HCV-associated diseases.

Most patients with HCV-associated lymphoma present with mild liver disease: a call to revise antiviral treatment prioritization

BACKGROUND & AIMS

Hepatitis C virus (HCV) is associated with development of B-cell non-Hodgkin lymphoma (HCV-NHL). Antiviral therapy (AVT) is prioritized in HCV-infected patients with significant fibrosis/cirrhosis. It is unknown whether current recommendations based on liver parameters cover the risk of HCV-NHL development. We aimed to evaluate the liver disease stages of patients with HCV-NHL.

METHODS

Hepatitis C virus-NHL patients seen at MD Anderson Cancer Center between 2008 and 2014 were evaluated for underlying liver disease within a year of HCV-NHL diagnosis by non-invasive fibrosis markers, radiology or liver biopsy. Included patients were observed retrospectively (2008-2012) or prospectively (2012-2014).

RESULTS

Eighty nine patients with HCV-NHL were evaluated. Most patients had genotype 1 (62%) infection, had diffuse large B cell lymphomas (62%), and detectable HCV RNA (90%) at NHL diagnosis. Notably, advanced liver disease (Metavir stage ≥ 3) was present in only 18% of the patients at the time of HCV-NHL diagnosis. All 53 patients with chronic HCV infection documented before lymphoma diagnosis were seen by HCV-treating physicians. Providers did not recommend AVT in almost one half of cases (44%), mostly because of the lack of advanced liver disease at HCV diagnosis (38%).

CONCLUSIONS

Most patients with HCV-NHL have mild liver disease at cancer diagnosis. Our findings suggest the need for early initiation of AVT in infected patients to eradicate HCV infection and its extra-hepatic manifestations. Treatment prioritization and cost must be weighed against the potential benefits of preventing NHL.

Sofosbuvir-based therapy cures hepatitis C virus infection after prior treatment failures in a patient with concurrent lymphoma

We report on the first well-tolerated and successful use of sofosbuvir-based therapy in a patient in whom chronic infection with hepatitis C had preceded the development of B-cell non-Hodgkin's lymphoma. The patient had previously failed numerous attempts to clear the hepatitis C virus with traditional antiviral schedules. We demonstrate that sofosbuvir-based therapy resulted in cure of hepatitis C in a patient who had relapsed during combination therapy with an NS5A inhibitor, an NS3 protease inhibitor and ribavirin, as well as treatment failures to multiple courses of interferon-based therapy. This report also suggests that eradication of hepatitis C virus may result in the short-term prevention of B-cell non-Hodgkin's lymphoma relapse. The findings from our case require further validation in future cohorts of patients.

Achieving sustained virological response: what's the impact on further hepatitis C virus-related disease?

Continuous hepatic inflammation as a result of chronic infection with the hepatitis C virus may lead to the development of fibrosis and eventually cirrhosis. At the stage of cirrhosis, patients are at elevated risk of liver failure and hepatocellular carcinoma, two complications that shorten their life expectancy. Survival may be further impaired by the extra-hepatic manifestations of chronic hepatitis C virus infection, such as diabetes mellitus and lymphoma. Sustained virological response (SVR) following antiviral therapy has been associated with regression of hepatic fibrosis as well as with a reduction in portal pressure, both important markers of liver disease severity. Long-term follow-up studies indicated that SVR was related not only to a reduced occurrence of solid clinical end points, including liver failure and hepatocellular carcinoma, but also cardiovascular events and malignant lymphomas. Together, these findings may explain the recently observed improved overall survival among patients who attained SVR, even in the case of advanced liver disease.

Long-term effect of HCV eradication in patients with mixed cryoglobulinemia: a prospective, controlled, open-label, cohort study

Limited data are available about the efficacy of antiviral treatment in hepatitis C virus (HCV)-associated mixed cryoglobulinemia (MC), especially concerning the long-term effects of HCV eradication. The aim of this study was to evaluate the influence of MC on the virological response and the long-term effects of viral eradication on MC. We prospectively enrolled 424 HCV(+) patients belonging to the following groups: MC syndrome (MCS)-HCV (121 patients with symptomatic MC), MC-HCV (132 patients with asymptomatic MC), and HCV (158 patients without MC). Pegylated interferon plus ribavirin treatment was administered according to standard protocols. Posttreatment follow-up ranged from 35 to 124 months (mean 92.5 months). A significant difference was observed in the rate of sustained virological response between the HCV group and both the MC-HCV (P = 0.009) and MC-HCV+MCS-HCV (P = 0.014) groups. Multivariate logistic regression analysis identified cryoglobulinemia as an independent prognostic factor of nonresponse. The clinical-immunological response in MCS-HCV correlated with the virological one. All patients with sustained virological response also experienced a sustained clinical response, either complete or partial. In the majority of sustained virological response patients all MCS symptoms persistently disappeared (36 patients, 57%); in only two (3%) did definite MCS persist. All virological nonresponders were also clinical nonresponders, in spite of a transient improvement in some cases. No evolution to lymphoma was observed. For the first time we have evaluated both the effects of interferon-based therapy on HCV patients with and without MC and with and without symptoms, as well as the long-term effects of viral eradication on MC.

CONCLUSION

MC is a negative prognostic factor of virological response. Clearance of HCV led to persistent resolution or improvement of MCS, strongly suggesting the need for a next generation of highly effective antiviral drugs.

Genetic diversity of the KIR/HLA system and susceptibility to hepatitis C virus-related diseases

Background

The variability in the association of host innate immune response to Hepatitis C virus (HCV) infection requires ruling out the possible role of host KIR and HLA genotypes in HCV-related disorders: therefore, we therefore explored the relationships between KIR/HLA genotypes and chronic HCV infection (CHC) as they relate to the risk of HCV-related hepatocarcinoma (HCC) or lymphoproliferative disease progression.

Methods and Findings

We analyzed data from 396 HCV-positive patients with CHC (n = 125), HCC (118), and lymphoproliferative diseases (153), and 501 HCV-negative patients. All were HIV and HBV negative. KIR-SSO was used to determine the KIR typing. KIR2DL5 and KIR2DS4 variants were performed using PCR and GeneScan analysis. HLA/class-I genotyping was performed using PCR-sequence-based typing. The interaction between the KIR gene and ligand HLA molecules was investigated. Differences in frequencies were estimated using Fisher’s exact test, and Cochran-Armitage trend test. The non-random association of KIR alleles was estimated using the linkage disequilibrium test. We found an association of KIR2DS2/KIR2DL2 genes, with the HCV-related lymphoproliferative disorders. Furthermore, individuals with a HLA-Bw6 KIR3DL1+ combination of genes showed higher risk of developing lymphoma than cryoglobulinemia. KIR2DS3 gene was found to be the principal gene associated with chronic HCV infection, while a reduction of HLA-Bw4 + KIR3DS1+ was associated with an increased risk of developing HCC.

Conclusions

Our data highlight a role of the innate-system in developing HCV-related disorders and specifically KIR2DS3 and KIR2D genes demonstrated an ability to direct HCV disease progression, and mainly towards lymphoproliferative disorders. Moreover the determination of KIR3D/HLA combination of genes direct the HCV progression towards a lymphoma rather than an hepatic disease. In this contest IFN-α therapy, a standard therapy for HCV-infection and lymphoproliferative diseases, known to be able to transiently enhance the cytotoxicity of NK-cells support the role of NK cells to counterstain HCV-related and lymphoproliferative diseases.

Cure of HCV related liver disease

Chronic hepatitis C virus (HCV) causes chronic liver injury and can lead to cirrhosis and hepatocellular carcinoma (HCC). HCV can also interact with the immune system to cause several HCV related disorders including essential mixed cryoglobulinemia, vasculitis, dermatitis, glomerulonephritis and lymphoma. A strong association between HCV and diabetes mellitus also exists. These extrahepatic features may lead to increased fatigue and a reduced quality of life. It is now possible to cure most patients with chronic HCV using oral antiviral therapy. Many of these HCV-related disorders and symptoms can be cured when HCV is eradicated. However, some patients may have irreversible injury to extrahepatic sites, cirrhosis that cannot resolve, an increased risk for HCC, persistent fatigue and a reduced quality of life, despite achieving sustained virological response.

Extrahepatic manifestations of chronic hepatitis C virus infection

Hepatitis C virus (HCV) infected patients are known to be at risk of developing liver complications i.e. cirrhosis and liver cancer. However, the risks of morbidity and mortality are underestimated because they do not take into account non-liver consequences of chronic hepatitis C virus infection. Numerous extrahepatic manifestations have been reported in up to 74% of patients, from perceived to disabling conditions. The majority of data concern hepatitis C virus-related autoimmune and/or lymphoproliferative disorders, from mixed cryoglobulinaemia vasculitis to frank lymphomas. More recently, other hepatitis C virus-associated disorders have been reported including cardiovascular, renal, metabolic, and central nervous system diseases. This review aims to outline most of the extrahepatic manifestations that are currently being investigated, including some of autoimmune and/or lymphoproliferative nature, and others in which the role of immune mechanisms appears less clear. Beyond the liver, hepatitis C virus chronic infection should be analyzed as a multifaceted systemic disease leading to heavy direct and indirect costs. The accurate consideration of extrahepatic consequences of such a systemic infection significantly increases the weight of its pathological burden. The need for effective viral eradication measures is underlined.

Hepatitis C virus-associated B-cell non-Hodgkin lymphomas

Epidemiological studies have demonstrated an increased risk of developing B-cell lymphomas in patients with chronic hepatitis C virus (HCV) infection. However, the strength of the association shows great geographic discrepancies, with higher relative risk in countries with high HCV prevalence. It remains unclear whether additional environmental and genetic factors are involved or if the international variability is simply a consequence of the variable infection prevalence. Therefore, a causal relationship remains controversial. Other confounding factors may affect the comparability of the different studies, including the method of HCV assessment, the selection of normal controls, the lymphoma classification used, and the year of publication. The most convincing proof is the observation, mainly limited to some indolent subtypes, of B-cell lymphoma regressions after HCV eradication with IFN and ribavirin. However, the molecular mechanisms of the HCV-induced lymphomagenesis are mainly hypothetical. According to the model considered to be most plausible, lymphoma growth is a consequence of the continuous antigenic stimulation of the B-cell immunologic response induced by the chronic viral infection. This review summarizes the current epidemiological and biological evidence of a role of HCV in lymphomagenesis, describing the putative mechanisms for a causative relationship. The clinical characteristics and management difficulties of the HCV-associated lymphomas are also discussed. HCV treatment with IFN cannot be given safely in concomitance with cytotoxic lymphoma treatment because of hematological and liver toxicity. However, novel and better tolerated antiviral regimens are under development and will hopefully make the treatment of both lymphoma and hepatitis easier in the future.

Hepatitis C infection and lymphoproliferative disease: Accidental comorbidities?

Chronic hepatitis C virus (HCV) infection has been associated with liver cancer and cirrhosis, autoimmune disorders such as thyroiditis and mixed cryoglobulinema, and alterations in immune function and chronic inflammation, both implicated in B cell lymphoproliferative diseases that may progress to non-Hodgkin lymphoma (NHL). HCV bound to B cell surface receptors can induce lymphoproliferation, leading to DNA mutations and/or lower antigen response thresholds. These findings and epidemiological reports suggest an association between HCV infection and NHL. We performed a systematic review of the literature to clarify this potential relationship. We searched the English-language literature utilizing Medline, Embase, Paper First, Web of Science, Google Scholar, and the Cochrane Database of Systematic Reviews, with search terms broadly defined to capture discussions of HCV and its relationship with NHL and/or lymphoproliferative diseases. References were screened to further identify relevant studies and literature in the basic sciences. A total of 62 reports discussing the relationship between HCV, NHL, and lymphoproliferative diseases were identified. Epidemiological studies suggest that at least a portion of NHL may be etiologically attributable to HCV, particularly in areas with high HCV prevalence. Studies that showed a lack of association between HCV infection and lymphoma may have been influenced by small sample size, short follow-up periods, and database limitations. The association appears strongest with the B-cell lymphomas relative to other lymphoproliferative diseases. Mechanisms by which chronic HCV infection promotes lymphoproliferative disease remains unclear. Lymphomagenesis is a multifactorial process involving genetic, environmental, and infectious factors. HCV most probably have a role in the lymphomagenesis but further study to clarify the association and underlying mechanisms is warranted.

Sustained virological response with telaprevir in 1,078 patients with advanced hepatitis C: the international telaprevir access program

BACKGROUND & AIMS

There is little information regarding the extent to which difficult to cure patients with advanced liver fibrosis, due to hepatitis C virus genotype-1 (HCV-1) can successfully and safely be treated with triple therapy with telaprevir (TVR), pegylated interferon alpha (P) and ribavirin (R). In the TVR early access program HEP3002 we aimed to explore treatment safety and efficacy, and identify predictors of sustained virological response at week 24 (SVR24).

METHODS

1078 patients with bridging fibrosis (n=552) or cirrhosis (n=526) diagnosed by either liver biopsy or non-invasive markers, with compensated bone marrow (neutrophils >1500/mm(3), Hb >12/13 g/dl) and liver function (Albumin >3.3g/dl, Platelets >90,000/ml) received TVR PR for 12 weeks, followed by a PR tail according to label.

RESULTS

Overall, 614 (57%) achieved SVR24 by intention-to-treat analysis. The SVR24 rate was 68% in 221 treatment naïve patients (62.8% F4), 72% in 356 prior relapsers (64.4% F4), 55% in 139 partial responders (53.2% F4), and 34% in 294 null responders (28.6% F4). The SVR24 rate to response-guided therapy (24 weeks treatment duration if undetectable viremia at weeks 4 and 12) was 84% in 222 naïve/relapser F3 patients. Independent predictors of response were: (A) F3 (odds ratio (OR)=1.51, 95% CI 1.31-2.00, p=0.005), (B) subtype 1b (OR=1.63, 95% CI 1.18-2.24, p=0.0029), (C) alpha-fetoprotein <10 ng/ml (OR=2.50, 95% CI 1.87-3.36, p<0.0001) and (D) any prior response other than null (OR=3.29, 95% CI 2.40-4.52, p<0.0001). SVR24 rose for patients who had more of these predictive factors: 6/32 (19%) for none, 38/139 (27%) for 1, 129/260 (50%) for 2, 202/329 (61%) for 3, and 194/235 (83%) for 4 factors. Grade 2-4 treatment-related adverse events (AE) were experienced by 719 (67%) patients; 169 (16%) discontinued therapy for AE and 7 (0.6%) died during the PR tail.

CONCLUSIONS

Naïve and experienced patients with advanced fibrosis or cirrhosis due to HCV-1 who have compensated bone marrow and liver function, can effectively and safely be treated by TVR triple therapy. Baseline predictors of outcome have been identified to optimize pre-treatment counselling.

Hepatitis C virus and lymphoma

Hepatitis C virus (HCV) is a hepatotrophic and lymphotrophic virus and is a global health problem. Cirrhosis and hepatocellular cancer are the most common complications of HCV. Association between HCV and B cell non-Hodgkin lymphomas (B-NHL) has been shown in epidemiological studies in the last 20 years. High prevalence of HCV infection among patients with NHL has been reported in the early 1990s by Ferri in Italy and this association has been confirmed in later studies. Geographically, HCV related NHL is highly variable and chronic rather than cleared HCV infection is required for lymphomagenesis. Although anti-HCV antibody test is the most commonly used technique in epidemiological studies, HCV-RNA is more useful test to detect the association between HCV and NHL. The optimal management of HCV related NHL is not clear. However, anti-viral treatment may be sufficient for cases with low grade and/or asymptomatic lymphomas, while immuno-chemotherapy is necessary, in spite of probable hepatic toxicity, in cases with high grade lymphomas.

Antiviral treatment in patients with indolent B-cell lymphomas associated with HCV infection: a study of the Fondazione Italiana Linfomi

BACKGROUND

Tumor regression after antiviral therapy (AT) is in favor of an etiological role of hepatitis C virus (HCV) in non-Hodgkin's B-cell lymphomas (NHL).

PATIENTS AND METHODS

We carried out a cohort study of 704 consecutive HIV-negative, HCV-positive patients with indolent NHL diagnosed and treated from 1993 to 2009 in 39 centers of the Fondazione Italiana Linfomi; 134 patients were managed with AT for lymphoma control.

RESULTS

For entire cohort, 5-year overall survival (OS) was 78% [95% confidence interval (CI): 74%-82%] and 5-year progression-free survival (PFS) was 48% (95% CI: 44%-53%). In multivariate analysis, the use of AT during the patients' life had positive impact on OS. Forty-four of the 100 patients treated with first-line AT achieved a complete remission (CR) and 33 a partial response (PR). HCV-RNA clearance was achieved in 80 patients and was related to lymphoma response. At a median follow-up of 3.6 years, 5-year PFS was 63% (95% CI: 50%-73%). CR + PR rate was 85% with AT as second-line treatment.

CONCLUSION

AT produces HCV-RNA clearance and consequent tumor regression in most patients with HCV-related indolent NHL. AT used at any time is associated with improved OS. Consequently, AT can be considered an option for patients with indolent lymphomas who do not need immediate cytoreductive treatment.

Role of microRNA profile modifications in hepatitis C virus-related mixed cryoglobulinemia

Hepatitis C virus infection is closely related to lymphoproliferative disorders (LPDs), including mixed cryoglobulinemia (MC) and some lymphomas. Modification of the expression of specific microRNAs (miRNAs) has been associated with different autoimmune diseases and/or LPDs. No data exist about the modifications in miRNA expression in HCV-associated LPDs. The aim of this study was to analyze the expression levels of a panel of miRNAs previously associated with autoimmune/LPDs in a large population of HCV patients with and without MC or non-Hodgkin’s lymphoma (NHL), to identify potential markers of evolution of HCV infection. PBMC expression of miR-Let-7d, miR-16, miR-21, miR-26b, miR-146a and miR-155 was evaluated by real-time PCR in 167 HCV patients (75 with MC [MC-HCV], 11 with HCV-associated NHL [NHL-HCV], 81 without LPD [HCV]) and in 35 healthy subjects (HS). A significant increase in miR-21 (p<0.001), miR-16 (p<0.01) and miR-155 (p<0.01) expression was detected in PBMCs from only NHL patients whereas a significant decrease in miR-26b was detected in both MC and NHL subjects (p<0.01) when compared to HS and HCV groups. A restoration of miR-26b levels was observed in the post-treatment PBMCs of 35 HCV-MC patients experiencing complete virological and clinical response following antiviral therapy. This study, for the first time, shows that specific microRNAs in PBMC from HCV patients who developed MC and/or NHL are modulated differently. The specific, reversible downregulation of miR-26b strongly suggests the key role it plays in the pathogenesis of HCV-related LPDs and its usefulness as a biomarker of the evolution of HCV infection to these disorders.

Hepatitis C virus (HCV)-related cryoglobulinemia: cryoglobulin type and anti-HCV profile

Cryoglobulin characteristics in chronic hepatitis C (CHC) might be of importance for knowing more about the pathogenesis and treatment of the disease. We aimed to investigate the relationship between cryoglobulin types and their specificity against hepatitis C virus (HCV) antigenic epitopes in CHC patients. We analyzed samples from 43 patients with HCV-associated cryoglobulinemia, of whom 4 had concomitant lymphoma. Cryoglobulins were measured, purified, typed by immunofixation electrophoresis, and tested for IgG and IgM anti-HCV antibodies by immunoblot analysis and an enzyme-linked immunosorbent assay (ELISA). Clinical and other laboratory data were recorded. The median cryocrit level of the tested samples was 6%. Type I cryoglobulins were detected in 9.3% (4/43) of the cryoprecipitates, and type II cryoglobulins were detected in 48.8% (21/43) of the cryoprecipitates. IgM monoclonal protein, mainly IgM(κ), was found in 92% (23/25) of type I and II cryoprecipitates. Type III cryoglobulins were identified in 41.9% (18/43) of the patients and were associated with high blood serum IgG levels. In 81.3% (13/16) of type II and 92.3% (12/13) of type III cryoglobulins, there was IgG reactivity against the viral core region. Ninety-two percent and 32% of IgG anti-HCV core-positive cryoprecipitates had additional specificities against the NS3 and NS4 regions, respectively. Also, IgM anti-HCV antibodies were detected in 31% of the cryoprecipitates. In conclusion, all types of cryoglobulins were found in patients with HCV-associated cryoglobulinemia, with type II being the most frequently identified. Type III cryoglobulins were common and were associated with high serum IgG levels. HCV-related cryoglobulins demonstrated IgM, and particularly IgG, anti-HCV specificities, mainly against the core and NS3 epitopes.

Assessing long-term treatment efficacy in chronic hepatitis B and C: between evidence and common sense

Chronic infection with the hepatitis B and C virus represents a major health problem worldwide, as it is estimated that roughly 400 and 200 million people respectively, are infected by each virus. By definition, any antiviral therapy that claims to be effective should have as its ultimate efficacy end point an improvement in patients' survival, or at least a reduction in the development rates of liver-related complications. However, this is extremely complicated to prove as the natural course of both viral diseases is extremely slow, requiring decades to evolve in cirrhosis and even more years to lead to liver complications. For this reason, clinicians and health authorities have relied on so called surrogate end points to assess the efficacy of any therapeutic intervention for viral hepatitis. Obviously, this allows for standardization in study designs that ultimately translates into an accelerated time frame for therapeutic drugs as well as healthcare innovations to enter the viral hepatitis clinical practice. However, it also calls for demonstration that surrogate end points in the treatment of patients with chronic hepatitis B or C are good and reliable markers of long-term efficacy.

Molecular signatures of hepatitis C virus (HCV)-induced type II mixed cryoglobulinemia (MCII)

The role of hepatitis C virus (HCV) infection in the induction of type II mixed cryoglobulinemia (MCII) and the possible establishment of related lymphoproliferative disorders, such as B-cell non-Hodgkin lymphoma (B-NHL), is well ascertained. However, the molecular pathways involved and the factors predisposing to the development of these HCV-related extrahepatic complications deserve further consideration and clarification. To date, several host- and virus-related factors have been implicated in the progression to MCII, such as the virus-induced expansion of selected subsets of B-cell clones expressing discrete immunoglobulin variable (IgV) gene subfamilies, the involvement of complement factors and the specific role of some HCV proteins. In this review, we will analyze the host and viral factors taking part in the development of MCII in order to give a general outlook of the molecular mechanisms implicated.

The hepatitis C virus infection as a systemic disease

Hepatitis C Virus (HCV) is a major health problem, infecting about 3 % of people worldwide and leading to liver as well as extrahepatic diseases. This justifies the definition of HCV infection as a systemic disease. Based on available data, the link between the virus and some of these extrahepatic disorders is certain, whereas for some others needs further confirmation. HCV-related lymphoproliferative disorders, ranging from benign, but pre-lymphomatous conditions, like mixed cryoglobulinemia, to frank lymphomas, represent the extrahepatic manifestations most closely related to HCV. The primary involvement of the liver and lymphatic system corresponds to the double viral tropism, being HCV able to infect both hepatic and lymphatic cells. Other HCV-associated disorders include renal, endocrine, dermatological, cardiovascular, rheumatologic and central nervous system diseases. On the whole, the HCV disease appears a very important, mainly hidden, public health problem leading to heavy direct and indirect costs. The possibility that HCV may be eradicated following antiviral therapy is important for both the therapeutic and preventive points of view, making the HCV disease an ideal model for pathogenetic studies.

Molecular signature in HCV-positive lymphomas

Hepatitis C virus (HCV) is a positive, single-stranded RNA virus, which has been associated to different subtypes of B-cell non-Hodgkin lymphoma (B-NHL). Cumulative evidence suggests an HCV-related antigen driven process in the B-NHL development. The underlying molecular signature associated to HCV-related B-NHL has to date remained obscure. In this review, we discuss the recent developments in this field with a special mention to different sets of genes whose expression is associated with BCR coupled to Blys signaling which in turn was found to be linked to B-cell maturation stages and NF-κb transcription factor. Even if recent progress on HCV-B-NHL signature has been made, the precise relationship between HCV and lymphoma development and phenotype signature remain to be clarified.

Hepatitis C virus infection in the immunocompromised host: a complex scenario with variable clinical impact

The relationship between Hepatitis C Virus (HCV) infection and immunosuppression is complex and multifaceted. Although HCV-related hepatocytolysis is classically interpreted as secondary to the attack by cytotoxic T lymphocytes against infected cells, the liver disease is usually exacerbated and more rapidly evolutive in immunosuppressed patients. This generally occurs during the immunosuppression state, and not at the reconstitution of the host response after immunosuppressive therapy discontinuation. The field of immunosuppression and HCV infection is complicated both by the different outcome observed in different situations and/or by contrasting data obtained in the same conditions, with several still unanswered questions, such as the opportunity to modify treatment schedules in the setting of post-transplant follow-up. The complexity of this field is further complicated by the intrinsic tendency of HCV infection in itself to lead to disorders of the immune system. This review will briefly outline the current knowledge about the pathogenesis of both hepatic and extrahepatic HCV-related disorders and the principal available data concerning HCV infection in a condition of impairment of the immune system. Attention will be especially focused on some conditions - liver or kidney transplantation, the use of biologic drugs and cancer chemotherapy - for which more abundant and interesting data exist.

HCV and lymphoproliferation

Hepatitis C virus (HCV) infection is a serious public health problem because of its worldwide diffusion and sequelae. It is not only a hepatotropic but also a lymphotropic agent and is responsible not only for liver injury--potentially evolving to cirrhosis and hepatocellular carcinoma--but also for a series of sometimes severely disabling extrahepatic diseases and, in particular, B-cell lymphoproliferative disorders. These latter range from benign, but prelymphomatous conditions, like mixed cryoglobulinemia, to frank lymphomas. Analogously with Helicobacter pylori related lymphomagenesis, the study of the effects of viral eradication confirmed the etiopathogenetic role of HCV and showed it is an ideal model for better understanding of the molecular mechanisms involved. Concerning these latter, several hypotheses have been proposed over the past two decades which are not mutually exclusive. These hypotheses have variously emphasized the important role played by sustained stimulation of the immune system by HCV, infection of the lymphatic cells, viral proteins, chromosomal aberrations, cytokines, or microRNA molecules. In this paper we describe the main hypotheses that have been proposed with the corresponding principal supporting data.

Pathogenetic mechanisms of hepatitis C virus-induced B-cell lymphomagenesis

Hepatitis C virus (HCV) infection is probably the most common chronic viral infection and affects an estimated 180 million people worldwide, accounting for 3% of the global population. Although the liver is considered to be the primary target, extrahepatic manifestations are well recognized among patients with chronic HCV infection. Epidemiological studies have clearly demonstrated a correlation between chronic HCV infection and occurrence of B-cell non-Hodgkin's lymphomas (B-NHL). The clinical evidence that antiviral therapy has a significant role in the treatment at least of some HCV-associated lymphoproliferative disorders, especially indolent B-NHL, further supports the existence of an etiopathogenetic link. However, the mechanisms exploited by HCV to induce B-cell lymphoproliferation have so far not completely clarified. It is conceivable that different biological mechanisms, namely, chronic antigen stimulation, high-affinity interaction between HCV-E2 protein and its cellular receptors, direct HCV infection of B-cells, and "hit and run" transforming events, may be combined themselves and cooperate in a multifactorial model of HCV-associated lymphomagenesis.

HCV proteins and immunoglobulin variable gene (IgV) subfamilies in HCV-induced type II mixed cryoglobulinemia: a concurrent pathogenetic role

The association between hepatitis C virus (HCV) infection and type II mixed cryoglobulinemia (MCII) is well established, but the role played by distinct HCV proteins and by specific components of the anti-HCV humoral immune response remains to be clearly defined. It is widely accepted that HCV drives the expansion of few B-cell clones expressing a restricted pool of selected immunoglobulin variable (IgV) gene subfamilies frequently endowed with rheumatoid factor (RF) activity. Moreover, the same IgV subfamilies are frequently observed in HCV-transformed malignant B-cell clones occasionally complicating MCII. In this paper, we analyze both the humoral and viral counterparts at the basis of cryoglobulins production in HCV-induced MCII, with particular attention reserved to the single IgV subfamilies most frequently involved.

HCV infection, B-cell non-Hodgkin’s lymphoma and immunochemotherapy: Evidence and open questions

There is plenty of data confirming that hepatitis C virus (HCV) infection is a predisposing factor for a B-cell non-Hodgkin’s lymphoma (B-NHL) outbreak, while relatively few reports have addressed the role of HCV in affecting B-NHL patients’ outcome. HCV infection may influence the short-term outcome of B-NHL because of the emergence of severe hepatic toxicity (HT) during immunochemotherapy. Furthermore, the long term outcome of HCV-related liver disease and patients’ quality of life will possibly be affected by Rituximab maintenance, multiple-lines of toxicity during chemotherapy and hematopoietic stem cell transplantation. In this review, data dealing with aggressive and low-grade B-NHL were separately analyzed. The few retrospective papers reporting on aggressive B-NHL patients showed that HCV infection is a risk factor for the outbreak of severe HT during treatment. This adverse event not infrequently leads to the reduction of treatment density and intensity. Existing papers report that low-grade B-NHL patients with HCV infection may have a more widespread disease, more frequent relapses or a lower ORR compared to HCV-negative patients. Notwithstanding, there is no statistical evidence that the prognosis of HCV-positive patients is inferior to that of HCV-negative subjects. HCV-positive prospective studies and longer follow-up are necessary to ascertain if HCV-positive B-NHL patients have inferior outcomes and if there are long term sequels of immunochemotherapies on the progression of liver disease.

Difference in malignancies of chronic liver disease due to non-alcoholic fatty liver disease or hepatitis C in Japanese elderly patients

AIM

  Malignancies that include hepatocellular carcinoma often occurred in patients with chronic liver disease. The aim of this retrospective match control study was to assess the cumulative development incidence and predictive factors for total malignancies in elderly Japanese patients with non-alcoholic hepatic diseases (NAFLD) or hepatitis C virus (HCV).

METHODS

  A total of 1600 NAFLD patients with age of ≥60 years were enrolled, and 1600 HCV patients with age of ≥60 years were selected as control by matching 1:1 with NAFLD group for age, sex, and follow-up period. The primary goal is the first development of malignancies. Evaluation was performed by the use of the Wilcoxon rank sum test, the Kaplan-Meier method, and Cox proportional hazard model. The mean observation period is 8.2 years in both NAFLD and HCV group, respectively.

RESULTS

  The number of patients with the development of malignancies was 167 in the NAFLD group and 395 in the HCV group. The 10th development rate of malignancies was 13.9% in the NAFLD group and 28.2% in the HCV group (risk ratio 2.27; P < 0.001). The incident rates of hepatocellular carcinoma in all the malignancies were 6.0% (10/167) in the NAFLD group and 67.6% (267/395) in the HCV group (P < 0.001). The malignancies in the NAFLD group were observed in the following order: gastric cancer 34 cases (20.4%) > colon cancer 31 cases (18.6%) > prostate cancer 21 cases (12.6%).

CONCLUSIONS

  The incident rates of hepatocellular carcinoma in all the malignancies were approximately 6% in the NAFLD group and two-thirds in the HCV group.

Hepatitis C and non-Hodgkin lymphoma: the clinical perspective

Hepatitis C virus (HCV) is a commonly transmitted infection that has both hepatic and extrahepatic repercussions. These range from the inflammatory to the oncologic with an undisputed link to hepatitis, liver cirrhosis, and hepatocellular carcinoma. Its role in the development of B cell non-Hodgkin lymphoma (B-NHL) is becoming better understood, leading to opportunities for research, therapy, and even prevention. Research in the field has progressed significantly over the last decade, with the number of patients diagnosed with HCV and B-NHL rising incrementally. It is therefore becoming crucial to fully understand the pathobiologic link of HCV in B cell lymphomagenesis and its optimal management in the oncologic setting.

Clinical drivers in naïve patient eligibility for treatment of chronic hepatitis C

Hepatitis C virus (HCV) infection represents a major health problem, being a leading cause of cirrhosis and liver transplantation worldwide. Viral eradication achieved by Peginterferon and Ribavirin therapy is the only therapeutic option that can prevent fibrosis progression in chronic hepatitis and liver-related complications in cirrhotic patients. Unfortunately, the occurrence of potentially serious side effects argues against universal treatment of HCV-infected patients. Indeed most scientific societies suggest that eligibility for therapy be based on baseline factors, the so called clinical drivers for treatment eligibility. Current international guidelines recommend focusing on the severity of liver disease, likelihood of treatment response in terms of chances of sustained virological response (SVR) to antiviral therapy and risk of serious adverse events when making treatment decisions. However, evidence exists that treatment may benefit also patients with mild fibrosis and that baseline predictions of a SVR are inaccurate because of the key role of HCV kinetics while on-therapy. An extended treatment programme is further supported by the fact that an increase in the number of patients treated would ultimately result in a long-term reduction of liver-related deaths.

Hepatitis C virus and GBV-C virus prevalence among patients with B-cell lymphoma in different European regions: a case-control study of the International Extranodal Lymphoma Study Group

Hepatitis C virus (HCV) infection is associated with some B-cell non-Hodgkin lymphoma (B cell-NHLs). Patients with HCV infection frequently show co-infections with GB virus C (GBV-C, formerly known as hepatitis G virus), and some studies have suggested a higher incidence of GBV-C infection in patients with B cell-NHLs. The aim of this study was to prospectively evaluate the association between HCV and/or GBV-C infection and B cell-NHLs in different geographic areas. One hundred thirty-seven lymphoma cases and 125 non-lymphoma matched controls were enrolled in an international case-control study conducted in Switzerland (Bellinzona), Spain (Barcelona) and England (Southampton) on samples collected from 2001 to 2002. In Bellinzona (41 cases and 81 controls), the overall prevalence of HCV was 3.3% (4.9% in NHLs), and the overall prevalence of GBV-C was 24% (22% in NHLs). In Barcelona (46 cases and 44 controls), the prevalence of HCV was 10% (8.7% in NHLs) and the prevalence of GBV-C 20% (13% in NHLs). There was no statistically significant difference in the frequency of both infections between patients with NHL and controls. In Southampton, 50 NHL cases were analysed, none of them was found to be HCV-positive; therefore, no control group was analysed and GBV-C analysis was not performed, too. Both in Bellinzona and in Barcelona, the seropositivity rate was significantly lower for HCV than for GBV-C, suggesting that their transmission can be independent. The incidence of HCV was significantly higher in Barcelona than that in Bellinzona. This study confirmed the existence of marked geographic differences in the prevalence of HCV in NHL but cannot provide any significant evidence for an association between HCV and/or GBV-C and B-cell NHLs.

Hepatitis C virus-related lymphomagenesis in a mouse model

B cell non-Hodgkin lymphoma is a typical extrahepatic manifestation frequently associated with hepatitis C virus (HCV) infection. The mechanism by which HCV infection leads to lymphoproliferative disorder remains unclear. Our group established HCV transgenic mice that expressed the full HCV genome in B cells (RzCD19Cre mice). We observed a 25.0% incidence of diffuse large B cell non-Hodgkin lymphomas (22.2% in male and 29.6% in female mice) within 600 days of birth. Interestingly, RzCD19Cre mice with substantially elevated serum-soluble interleukin-2 receptor α-subunit (sIL-2Rα) levels (>1000 pg/mL) developed B cell lymphomas. Another mouse model of lymphoproliferative disorder was established by persistent expression of HCV structural proteins through disruption of interferon regulatory factor-1 (irf-1^_/_/CN2 mice). Irf-1^_/_/CN2 mice showed extremely high incidences of lymphomas and lymphoproliferative disorders. Moreover, these mice showed increased levels of interleukin (IL)-2, IL-10, and Bcl-2 as well as increased Bcl-2 expression, which promoted oncogenic transformation of lymphocytes.

Hepatitis viruses and non-Hodgkin lymphoma: epidemiology, mechanisms of tumorigenesis, and therapeutic opportunities

Over the past 2 decades considerable evidence has accumulated on the association between hepatitis C virus (HCV) and hepatitis B virus (HBV) and several hematologic malignancies, most notably B-cell non-Hodgkin lymphoma (NHL). In this review we summarize this evidence, address possible mechanisms whereby hepatitis viruses may contribute to lymphomagenesis, and discuss the therapeutic fallouts from this knowledge. Most of this evidence is on HCV, and this is the main focus of the review. Moreover, we mainly address the association with NHL, the most prevalent hematologic malignancy, and the most extensively investigated with regard to an association with hepatitis viruses. Available evidence on the association with other hematologic malignancies is also addressed briefly.

Persistent expression of the full genome of hepatitis C virus in B cells induces spontaneous development of B-cell lymphomas in vivo

Extrahepatic manifestations of hepatitis C virus (HCV) infection occur in 40%-70% of HCV-infected patients. B-cell non-Hodgkin lymphoma is a typical extrahepatic manifestation frequently associated with HCV infection. The mechanism by which HCV infection of B cells leads to lymphoma remains unclear. Here we established HCV transgenic mice that express the full HCV genome in B cells (RzCD19Cre mice) and observed a 25.0% incidence of diffuse large B-cell non-Hodgkin lymphomas (22.2% in males and 29.6% in females) within 600 days after birth. Expression levels of aspartate aminotransferase and alanine aminotransferase, as well as 32 different cytokines, chemokines and growth factors, were examined. The incidence of B-cell lymphoma was significantly correlated with only the level of soluble interleukin-2 receptor α subunit (sIL-2Rα) in RzCD19Cre mouse serum. All RzCD19Cre mice with substantially elevated serum sIL-2Rα levels (> 1000 pg/mL) developed B-cell lymphomas. Moreover, compared with tissues from control animals, the B-cell lymphoma tissues of RzCD19Cre mice expressed significantly higher levels of IL-2Rα. We show that the expression of HCV in B cells promotes non-Hodgkin-type diffuse B-cell lymphoma, and therefore, the RzCD19Cre mouse is a powerful model to study the mechanisms related to the development of HCV-associated B-cell lymphoma.

Reactivation of hepatitis D virus after chemotherapy for diffuse large B cell lymphoma despite lamivudine prophylaxis

We describe a case of reactivation of hepatitis D virus (HDV) in a patient treated with chemotherapy for a diffuse large B cell lymphoma despite lamivudine prophylaxis. This case suggests that previously cleared HDV should be considered when administering chemotherapy to patients with lymphoma.

Occult hepatitis C virus infection: what does it mean?

Occult hepatitis C virus infection (OCI) is a recently identified entity of which the existence became evident when nucleic acid amplification assays of enhanced sensitivity were introduced for the detection of hepatitis C virus (HCV) genome and its replication. This form of HCV infection has been found to persist in the presence of antibodies against HCV and normal levels of liver enzymes for years after spontaneous or antiviral therapy-induced resolution of hepatitis C and, therefore, can be termed as secondary OCI. HCV RNA in OCI circulate at fluctuating levels normally not exceeding 200 genome copies per millilitre of serum or plasma, while low levels of virus genome and its replicative intermediate RNA-negative strand are detectable in the liver and, importantly, immune cells, which provide an opportunity to detect active virus replication without the need for acquiring a liver biopsy. In addition to secondary OCI, a form of OCI accompanied by persistently moderately elevated serum liver enzymes in the absence of antibodies to HCV, which can be termed as cryptogenic OCI, has also been described. The current understanding of the nature and characteristics of OCI, methods and pitfalls of its detection, as well as the documented and expected pathological consequences of OCI will be summarized in this review.