Risk of non-Hodgkin lymphoma and lymphoproliferative precursor diseases in US veterans with hepatitis C virus

The cryoglobulinaemias

Cryoglobulins are immunoglobulins that precipitate in vitro at temperatures less than 37°C and produce organ damage through two main pathways: vascular sludging (hyperviscosity syndrome, mainly in type I cryoglobulinaemia) and immune-mediated mechanisms (principally vasculitis, in mixed cryoglobulinaemia). Cryoglobulinaemia is associated with many illnesses, which can be broadly grouped into infections, autoimmune disorders, and malignancies; the most common cause is infection with hepatitis C virus. Mixed cryoglobulinaemic syndrome is diagnosed when a patient has typical organ involvement (mainly skin, kidney, or peripheral nerve) and circulating cryoglobulins. Cutaneous purpura is the most common manifestation of cryoglobulinaemic vasculitis. The most frequently affected internal organs are the peripheral nerves, kidneys, and joints. The course varies widely and prognosis is influenced by both cryoglobulinaemic damage to vital organs and by comorbidities associated with underlying diseases. More than 90% of cases of cryoglobulinaemia have a known underlying cause; therefore treatment is focused on the cause of the disorder rather than merely symptomatic relief. Studies suggest that both combined or sequential antiviral therapies and targeted biological treatments might be more effective than monotherapy.

Hepatitis C virus-related B cell subtypes in non Hodgkin's lymphoma

AIM

To evaluate if indolent B cell-non Hodgkin's lymphoma (B-NHL) and diffuse large B-cell lymphoma (DLBCL) in hepatitis C virus (HCV) positive patients could have different biological and clinical characteristics requiring different management strategies.

METHODS

A group of 24 HCV related B-NHL patients (11 indolent, 13 DLBCL) in whom the biological and clinical characteristics were described and confronted. Patients with DLBCL were managed with the standard of care of treatment. Patients with indolent HCV-related B-NHL were managed with antiviral treatment pegylated interferon plus ribavirin and their course observed. The outcomes of the different approaches were compared.

RESULTS

Patients with DLBCL had a shorter duration of HCV infection and a higher prevalence of HCV genotype 1 compared to patients with indolent B-NHL in which HCV genotype 2 was the more frequent genotype. Five of the 9 patients with indolent HCV-related B-NHL treated with only antiviral therapy, achieved a complete response of their onco-haematological disease (55%). Seven of the 13 DLBCL patients treated with immunochemotheraphy obtained a complete response (54%).

CONCLUSION

HCV genotypes and duration of HCV infection differed between B-NHL subtypes. Indolent lymphomas can be managed with antiviral treatment, while DLBCL is not affected by the HCV infection.

Association between chronic viral hepatitis infection and breast cancer risk: a nationwide population-based case-control study

Background

In Taiwan, there is a high incidence of breast cancer and a high prevalence of viral hepatitis. In this case-control study, we used a population-based insurance dataset to evaluate whether breast cancer in women is associated with chronic viral hepatitis infection.

Methods

From the claims data, we identified 1,958 patients with newly diagnosed breast cancer during the period 2000-2008. A randomly selected, age-matched cohort of 7,832 subjects without cancer was selected for comparison. Multivariable logistic regression models were constructed to calculate odds ratios of breast cancer associated with viral hepatitis after adjustment for age, residential area, occupation, urbanization, and income. The age-specific (<50 years and ≥50 years) risk of breast cancer was also evaluated.

Results

There were no significant differences in the prevalence of hepatitis C virus (HCV) infection, hepatitis B virus (HBV), or the prevalence of combined HBC/HBV infection between breast cancer patients and control subjects (p = 0.48). Multivariable logistic regression analysis, however, revealed that age <50 years was associated with a 2-fold greater risk of developing breast cancer (OR = 2.03, 95% CI = 1.23-3.34).

Conclusions

HCV infection, but not HBV infection, appears to be associated with early onset risk of breast cancer in areas endemic for HCV and HBV. This finding needs to be replicated in further studies.

Antibody V(h) repertoire differences between resolving and chronically evolving hepatitis C virus infections

Despite the production of neutralizing antibodies to hepatitis C virus (HCV), many patients fail to clear the virus and instead develop chronic infection and long-term complications. To understand how HCV infection perturbs the antibody repertoire and to identify molecular features of antibody genes associated with either viral clearance or chronic infection, we sequenced the V(D)J region of naïve and memory B cells of 6 persons who spontaneously resolved an HCV infection (SR), 9 patients with a newly diagnosed chronically evolving infection (CE), and 7 healthy donors. In both naïve and memory B cells, the frequency of use of particular antibody gene subfamilies and segments varied among the three clinical groups, especially between SR and CE. Compared to CE, SR antibody genes used fewer VH, D and JH gene segments in naïve B cells and fewer VH segments in memory B cells. SR and CE groups significantly differed in the frequency of use of 7 gene segments in naïve B cell clones and 3 gene segments in memory clones. The nucleotide mutation rates were similar among groups, but the pattern of replacement and silent mutations in memory B cell clones indicated greater antigen selection in SR than CE. Greater clonal evolution of SR than CE memory B cells was revealed by analysis of phylogenetic trees and CDR3 lengths. Pauciclonality of the peripheral memory B cell population is a distinguishing feature of persons who spontaneously resolved an HCV infection. This finding, previously considered characteristic only of patients with HCV-associated lymphoproliferative disorders, suggests that the B cell clones potentially involved in clearance of the virus may also be those susceptible to abnormal expansion.

Epidemiology and etiology of mantle cell lymphoma and other non-Hodgkin lymphoma subtypes

We aimed to give an overview of the descriptive epidemiology and etiology of mantle cell lymphoma (MCL) in the context of all non-Hodgkin lymphoma (NHL) and major NHL subtypes, based on available published reports. In retrospective case series, MCL cases represent between 2 and 10% of all NHL. Population-based studies of MCL incidence by basic demographic characteristics are limited to the past 15-20 years and to Europe and the US. In both regions, average incidence rates of approximately 0.5 cases per 100,000 person-years were reported, with a male-to-female ratio of 2.3-2.5:1, and a median age at diagnosis of close to 70 years. Some data suggest a possible increase in MCL incidence over the last two decades, but the observation may also reflect improved diagnostics. The causes of MCL are not known. Studies of potential risk factors of MCL are few and conducted primarily within the framework of all NHL. Moderate associations with MCL risk have been reported for Borrelia burgdorferi infection, family history of hematopoietic malignancies, and genetic variation in the interleukin-10 and tumor necrosis factor genes, but findings remain unconfirmed. Large multicenter studies are needed to address these and other factors in risk of MCL with sufficient statistical power in the future.

Thyroid Dysfunction and Long-term Outcome during and after Interferon-alpha Therapy in Patients with Chronic Hepatitis C

Introduction: Thyroid dysfunction (TD) is a well-established adverse effect in chronic hepatitis C virus (HCV)-infected patients, treated with interferon-alpha (IFN-α), with or without ribavirin. However, the long-term outcome is not well-studied. The purpose of this study was to estimate the prevalence and long-term outcome of TD after HCV-therapy. Materials and Methods: Retrospective analysis of 109 HCV-treated patients (for 6 to 12 months, according to HCV genotype), for the period 1996 to 2008. Thyroid function tests were performed every 3 months during therapy and after discontinuation (3 months to 12 years). Routine laboratory tests and virological assessment were performed according to generally accepted practice. Results: TD was observed in 26 patients (23.85%). The positive and negative predictive value for thyroid autoantibodies (ATA) was 80% and 72.7%, respectively. Relative risk for those with positive ATA was 2.9 (95% CI: 1.6 to 5.3, P = 0.014). The median duration of TD was 12.0 months (min: 3; max: 132). The median follow-up period for the patients with TD was 25.5 months (min: 12; max: 144). Finally, 15 patients developed permanent TD (57.69%), compared to 11 with temporary TD (42.31%). Sex is a risk factor for TD, as there were more females than males affected (P = 0.011). Genotype, viral load, time of HCV-exposure prior to therapy, and virological response did not differ between patients with and without TD. Conclusion: TD among HCV-treated patients was more frequent than usually reported, with >50% developing permanent TD. ATA status may play a role in estimating the risk of subsequent TD. Women appear to be more vulnerable to TD than men. Key words: Cirrhosis, Hepatitis C, Interferon, Thyroid autoimmunity, Thyroid disease

What causes Waldenström's macroglobulinemia: genetic or immune-related factors, or a combination?

Population-based studies suggest a role for chronic immune stimulation and genetic factors in the causation of lymphoplasmacytic lymphoma (LPL)/Waldenström's macroglobulinemia (WM). In this review we summarize and discuss our current understanding on etiology and pathogenesis of LPL/WM. We also highlight on gaps in the literature and propose future directions for population-based and molecular studies designed to expand our knowledge and uncover biological underpinnings of identified associations. Further, we address clinical implications and provide perspective on the relevance of these data for patient counseling and clinical follow-up.

Liver cancer and non-Hodgkin lymphoma in hepatitis C virus-infected patients: results from the DANVIR cohort study

Hepatitis C virus (HCV)-infection can cause hepatocellular carcinoma (HCC) and most likely non-Hodgkin lymphoma (NHL). No studies have compared the risk of these cancers between patients with chronic and cleared HCV-infection. The aim of this study was to estimate the 10-year risk of HCC and NHL in HCV-infected patients and to compare the risk of these cancers between HCV-infected patients and the general population in Denmark and between patients with chronic and cleared HCV-infection. Nationwide cohorts were used: 11,975 HCV-infected patients in the DANVIR cohort and 71,850 individuals from an age- and gender-matched general population cohort. Within DANVIR, 4,158 patients with chronic HCV-infection and 2,427 patients with cleared HCV-infection were studied. The 10-year risks of HCC and NHL in HCV-infected patients were 1.0% [95% confidence interval (CI): 0.8-1.3%] and 0.1% (95% CI: 0.1-0.2%), respectively. Compared to the general population, HCV-infected patients had a 62.91-fold increased risk of HCC (95% CI: 28.99-136.52), a 29.97-fold increased risk of NHL during the first year of follow-up (95% CI: 6.08-147.84), and a 1.26-fold increased risk of NHL after the first year (95% CI: 0.36-4.41). Chronic HCV-infection was associated with a 4.71-fold increased risk of HCC (95% CI: 1.67-13.32) compared to cleared HCV-infection; 5 and 0 events of NHL occurred in patients with chronic and cleared HCV-infection, respectively. HCC-risk is increased substantially in HCV-infected patients compared to the general population. Chronic as opposed to cleared HCV-infection increases the risk of HCC and perhaps NHL.

High prevalence of polyclonal hypergamma-globulinemia in adult males in Ghana, Africa

Chronic antigenic stimulation is associated with hypergamma-globulinemia. Higher rates of hypergamma-globulinemia in tropical populations are maintained even with migration to temperate regions. We conducted a population-based screening study to assess the prevalence and risk factors for hypergamma-globulinemia in Ghana, Africa. 917 Ghanaian males (50-74 years) underwent in-person interviews and health examinations. Serum from all persons was analyzed by electrophoresis performed on agarose gel; serum with a discrete/localized band was subjected to immunofixation. 54 persons with monoclonal proteins were excluded and 17 samples were insufficient for analysis. Using logistic regression and Chi-square statistics we analyzed patterns of hypergamma-globulinemia. Among 846 study subjects, the median γ-globulin level was 1.86 g/dL. On the basis of a U.S. reference, 616 (73%) had hypergamma-globulinemia (>1.6 g/dL) and 178 (21%) had γ-globulin levels >2.17 gm/dl. On multivariate analyses, lower education status (P = 0.0013) and never smoking (P = 0.038) were associated with increased γ-globulin levels. Self-reported history of syphilis was associated with hypergamma-globulinemia. We conclude that three quarters of this population-based adult Ghanaian male sample had hypergamma-globulinemia with γ-globulin levels >1.6 g/dL. Future studies are needed to uncover genetic and environmental underpinnings of our finding, and to define the relationship between hypergamma-globulinemia, monoclonal gammopathy of undetermined significance (MGUS), and multiple myeloma.

Frequency of HCV infection in renal cell carcinoma patients

Chronic infections with hepatitis C virus (HCV) are frequently pronounced in the etiology of malignancies especially in hepatocellular carcinoma. The association between HCV and risk of renal cell carcinoma (RCC) development has been stated recently. The authors retrospectively evaluated hepatitis serology for HCV and HBV in patients who had RCC diagnosis between 2005 and 2010 in six oncology centers. Control group was also included from the three different published studies that hepatitis serology studied in healthy people that has been living in the same geographic regions. Histologically confirmed 903 RCC cases and 5,267 healthy subjects were included the study. Median age at diagnosis of RCC was 58 (range: 26-89). There was no increase in HCV positivity in RCC patients compared to healthy control group (1.7 vs. 1.5%; P = 0.77). Frequency of HBsAg positivity was 4.4 and 4.1% in RCC and control groups, respectively (P = 0.65). There is no increase in frequency of HCV and HBsAg positivity in RCC patients. HCV positivity in RCC patients were not different from the healthy people.

Clonal B cells in patients with hepatitis C virus-associated mixed cryoglobulinemia contain an expanded anergic CD21low B-cell subset

Hepatitis C virus (HCV) is associated with the B-cell lymphoproliferative disorders mixed cryoglobulinemia (MC) and non-Hodgkin lymphoma. We have previously reported that HCV(+)MC(+) patients have clonal expansions of hypermutated, rheumatoid factor-bearing marginal zone-like IgM(+)CD27(+) peripheral B cells using the V(H)1-69 gene. Here we coupled transcriptional profiling with immunophenotypic and functional studies to ascertain these cells' role in MC pathogenesis. Despite their fundamental role in MC disease, these B cells have overall transcriptional features of anergy and apoptosis instead of neoplastic transformation. Highly up-regulated genes include SOX5, CD11C, galectin-1, and FGR, similar to a previously described FCRL4(+) memory B-cell subset and to an "exhausted," anergic CD21(low) memory B-cell subset in HIV(+) patients. Moreover, HCV(+)MC(+) patients' clonal peripheral B cells are enriched with CD21(low), CD11c(+), FCRL4(high), IL-4R(low) memory B cells. In contrast to the functional, rheumatoid factor-secreting CD27(+)CD21(high) subset, the CD27(+)CD21(low) subpopulation exhibits decreased calcium mobilization and does not efficiently differentiate into rheumatoid factor-secreting plasmablasts, suggesting that a large proportion of HCV(+)MC(+) patients' clonally expanded peripheral B cells is prone to anergy and/or apoptosis. Down-regulation of multiple activation pathways may represent a homeostatic mechanism attenuating otherwise uncontrolled stimulation of circulating HCV-containing immune complexes.

Identification and application of biomarkers in molecular and genomic epidemiologic research

Biomarkers are characteristic biological properties that can be detected and measured in a variety of biological matrices in the human body, including the blood and tissue, to give an indication of whether there is a threat of disease, if a disease already exists, or how such a disease may develop in an individual case. Along the continuum from exposure to clinical disease and progression, exposure, internal dose, biologically effective dose, early biological effect, altered structure and/or function, clinical disease, and disease progression can potentially be observed and quantified using biomarkers. While the traditional discovery of biomarkers has been a slow process, the advent of molecular and genomic medicine has resulted in explosive growth in the discovery of new biomarkers. In this review, issues in evaluating biomarkers will be discussed and the biomarkers of environmental exposure, early biologic effect, and susceptibility identified and validated in epidemiological studies will be summarized. The spectrum of genomic approaches currently used to identify and apply biomarkers and strategies to validate genomic biomarkers will also be discussed.

Hyperphosphorylated paratarg-7: a new molecularly defined risk factor for monoclonal gammopathy of undetermined significance of the IgM type and Waldenstrom macroglobulinemia

We recently described paratarg-7 (P-7), a protein of unknown function, as the target of 15% of immunoglobulin A (IgA) and IgG paraproteins in monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma. To determine the frequency of P-7 as a paraprotein target in IgM-MGUS and Waldenström macroglobulinemia (WM), sera from patients with IgM-MGUS/WM were tested for reactivity with recombinant P-7 by enzyme-linked immunoabsorbent assay. The specificity of the paraprotein-mediated reaction was shown by absorption studies and cloning of the respective B-cell receptor. The paraproteins of 18 (9 WM and 9 IgM-MGUS) of 161 patients (11%) reacted with P-7. Isoelectric focusing and phosphatase treatment showed that P-7 was hyperphosphorylated (pP-7) in all patients with an anti-P-7-specific IgM paraprotein tested. Because only 4 of 200 healthy controls (2%) were carriers of pP-7, pP-7 carrier state is associated with a significantly increased risk (odds ratio = 6.2; P = .001) for developing IgM-MGUS/MW. Family analyses showed that the pP-7 carrier state is inherited as a dominant trait. After IgA/IgG-MGUS and multiple myeloma, IgM-MGUS/WM is the second neoplasia associated with pP-7 carrier state. The dominant inheritance of pP-7 explains cases of familial IgM-MGUS/WM and enables the identification of family members at increased risk.

Chronic hepatitis virus infection in patients with multiple myeloma: clinical characteristics and outcomes

OBJECTIVES

Cytotoxic agents and steroids are used to treat lymphoid malignancies, but these compounds may exacerbate chronic viral hepatitis. For patients with multiple myeloma, the impact of preexisting hepatitis virus infection is unclear. The aim of this study is to explore the characteristics and outcomes of myeloma patients with chronic hepatitis virus infection.

METHODS

From 2003 to 2008, 155 myeloma patients were examined to determine their chronic hepatitis virus infection statuses using serologic tests for the hepatitis B (HBV) and C viruses (HCV). Clinical parameters and outcome variables were retrieved via a medical chart review.

RESULTS

The estimated prevalences of chronic HBV and HCV infections were 11.0% (n = 17) and 9.0% (n = 14), respectively. The characteristics of patients who were hepatitis virus carriers and those who were not were similar. However, carrier patients had a higher prevalence of conventional cytogenetic abnormalities (64.3% vs. 25.0%). The cumulative incidences of grade 3-4 elevation of the level of alanine transaminase, 30.0% vs. 12.0%, and hyperbilirubinemia, 20.0% vs. 1.6%, were higher in carriers as well. In a Kaplan-Meier analysis, carrier patients had worse overall survival (median: 16.0 vs. 42.4 months). The prognostic value of carrier status was not statistically significant in the multivariate analysis, but an age of more than 65 years old, the presence of cytogenetic abnormalities, a beta-2-microglobulin level of more than 3.5 mg/L, and a serum creatinine level of more than 2 mg/ dL were independent factors associated with poor prognosis.

CONCLUSION

Myeloma patients with chronic hepatitis virus infections might be a distinct subgroup, and close monitoring of hepatic adverse events should be mandatory.

Hepatitis C virus inhibits DNA damage repair through reactive oxygen and nitrogen species and by interfering with the ATM-NBS1/Mre11/Rad50 DNA repair pathway in monocytes and hepatocytes

Hepatitis C virus (HCV) infection is associated with the development of hepatocellular carcinoma and putatively also non-Hodgkin's B cell lymphoma. In this study, we demonstrated that PBMCs obtained from HCV-infected patients showed frequent chromosomal aberrations and that HCV infection of B cells in vitro induced enhanced chromosomal breaks and sister chromatid exchanges. HCV infection hypersensitized cells to ionizing radiation and bleomycin and inhibited nonhomologous end-joining repair. The viral core and nonstructural protein 3 proteins were shown to be responsible for the inhibition of DNA repair, mediated by NO and reactive oxygen species. Stable expression of core protein induced frequent chromosome translocations in cultured cells and in transgenic mice. HCV core protein binds to the NBS1 protein and inhibits the formation of the Mre11/NBS1/Rad50 complex, thereby affecting ATM activation and inhibiting DNA binding of repair enzymes. Taken together, these data indicate that HCV infection inhibits multiple DNA repair processes to potentiate chromosome instability in both monocytes and hepatocytes. These effects may explain the oncogenicity and immunological perturbation of HCV infection.

Manifestations of chronic hepatitis C virus infection beyond the liver

In addition to its effects in the liver, chronic hepatitis C virus (HCV) infection can have serious consequences for other organ systems. Extrahepatic manifestations include mixed cryoglobulinemia (MC) vasculitis, lymphoproliferative disorders, renal disease, insulin resistance, type 2 diabetes, sicca syndrome, rheumatoid arthritis-like polyarthritis, and autoantibody production; reductions in quality of life involve fatigue, depression, and cognitive impairment. MC vasculitis, certain types of lymphoma, insulin resistance, and cognitive function appear to respond to anti-HCV therapy. However, treatments for HCV and other biopsychosocial factors can reduce quality of life and complicate management. HCV treatment has a high overall cost that increases when extrahepatic manifestations are considered. HCV appears to have a role in the pathogenesis of MC vasculitis, certain types of lymphoma, and insulin resistance. Clinicians who treat patients with HCV infections should be aware of potential extrahepatic manifestations and how these can impact and alter management of their patients.

Hepatitis C virus infection and increased risk of cerebrovascular disease

BACKGROUND AND PURPOSE

The association between hepatitis C virus (HCV) infection and cerebrovascular disease remains controversial. This study aimed to assess the risk of lethal cerebrovascular diseases associated with chronic HCV infection.

METHODS

In this community-based prospective cohort study, 23 665 residents (aged 30 to 65 years) were enrolled in 1991 to 1992. They were personally interviewed using structured questionnaires and provided blood samples for various serological and biochemical tests at study entry. Serum HCV RNA level and HCV genotype were tested for participants seropositive for antibodies against HCV (anti-HCV). Deaths from cerebrovascular disease during follow-up were ascertained by computerized linkage with National Death Certification profiles from 1991 to 2008 (International Classification of Diseases, 9th Revision 430 to 438). Multivariate-adjusted hazard ratio with 95% CI was estimated for each risk predictor.

RESULTS

There were 255 cerebrovascular deaths during 382 011 person-years of follow-up. The cumulative risk of cerebrovascular deaths was 1.0% and 2.7% for seronegatives and seropositives of anti-HCV, respectively (P<0.001). The hazard ratio (95% CI) of cerebrovascular death was 2.18 (1.50 to 3.16) for anti-HCV seropositives after adjustment for several conventional risk factors of cerebrovascular disease. Compared with participants seronegative for anti-HCV as the referent, the multivariate-adjusted hazard ratio (95% CI) was 1.40 (0.62 to 3.16), 2.36 (1.42 to 3.93), and 2.82 (1.25 to 6.37), respectively, for anti-HCV-seropositive participants with undetectable, low, and high serum levels of HCV RNA (P<0.001 for trend). However, no significant association was observed between HCV genotype and cerebrovascular death.

CONCLUSIONS

Chronic HCV infection is an independent risk predictor of cerebrovascular deaths showing a biological gradient of cerebrovascular mortality with increasing serum HCV RNA level.

Blood transfusions and the subsequent risk of hematologic malignancies

BACKGROUND

Blood transfusions are associated with viral transmission and immunomodulation, perhaps increasing subsequent risk of hematologic malignancies (HMs). Prior studies of transfusion recipients have lacked details on specific HM subtypes.

STUDY DESIGN AND METHODS

Risk of HM after blood transfusion was evaluated in a US population-based case-control study (77,488 elderly HM cases identified through cancer registries, 154,509 controls). Transfusions were identified using linked Medicare hospitalization claims. Polytomous logistic regression was used to calculate odds ratios (ORs) associating transfusion and HM subtypes by features suggestive of a causal relationship.

RESULTS

A history of transfusion was present in 7.9% of HM cases versus 5.9% of controls. Associations for most HM subtypes suggested reverse causality: ORs were elevated only during the shortest latency periods; ORs for unspecified anemia and gastrointestinal bleeding, which may be related to undiagnosed HM, were stronger than for surgeries, which are unlikely to be related to HM; and/or there was no dose response. In contrast, risk for lymphoplasmacytic lymphoma (1397 cases) was elevated at long latency (OR, 1.56 at 10+ years after transfusion), after transfusions related to surgeries (OR, 1.22-1.47), and in a dose-response relationship with number of transfusion-related hospitalizations (OR, 1.53 with one hospitalization; OR, 1.80 with two or more hospitalizations, p trend < 0.0001). Risk for marginal zone lymphoma (1915 cases) was also elevated at 10+ years after transfusion (OR, 1.80).

CONCLUSION

Consistent with prior studies, blood transfusions did not increase risk of most HM subtypes. Patterns of elevated risk for lymphoplasmacytic and marginal zone lymphomas suggest an etiologic role for transfusion.

Ten years later: a single hospital experience with malignancy in HIV/AIDS

BACKGROUND AND OBJECTIVE

We present our experience in the era of HAART with 5,112 patients having HIV infection or AIDS, treated between 2002 and 2006 in our hospital, 182 of whom had malignancies (3.56%). We compared our findings to those from a similar cohort of patients studied 10 years earlier.

METHODS

The charts were reviewed and data was electronically collected as in our 1993-1998 study. Similar statistical analyses were performed in both studies and the results were compared.

RESULTS

For the current study the average patient age increased by 9 years. A decrease in AIDS-defining cancers (ADC), from 63.6% to 37.3% and a higher incidence of non-AIDS-defining cancers (NADC), 62.7 as opposed to 37.9% was found. No decrease in the incidence of non-Hodgkin's B cell lymphoma (NHL) was noted. There was an increase in the number of opportunistic infections notably hepatitis C virus (HCV) and hepatitis B virus (HBV).

CONCLUSIONS

HIV/AIDS patients on HAART are older, have lower rates of AIDS related Kaposi's sarcoma and a higher incidence of NADCs than did patients in the early HAART era. No decrease in the proportion of NHL was observed.

Demyelinating neuropathy in patients with hepatitis C virus infection

Infection with hepatitis C virus (HCV) can be associated with demyelinating polyneuropathy that may be responsive to immunomodulatory therapy. In this case report series, we review four patients (all male, ages 47-60 years) with HCV and demyelinating polyneuropathy. Two of the four patients were diagnosed with HCV during the course of initial neuropathy evaluation. All patients had sensory loss, absent/diminished reflexes, lower extremity weakness (except for one patient), and demyelinating electrodiagnostic features. Three patients had polyclonal hypergammaglobulinemia and one patient had IgM monoclonal gammopathy. Intravenous immunoglobulin resulted in improvement in three patients; one patient had no benefit from rituximab therapy, but his symptoms have been stable. Demyelinating neuropathy may develop in patients with HCV unrelated to antiviral therapy. Immunomodulatory therapy may be beneficial in some cases. Testing for HCV should be considered, especially in patients with hypergammaglobulinemia or IgM monoclonal gammopathy.

Persistent infection by HCV and EBV in peripheral blood mononuclear cells and risk of non-Hodgkin's lymphoma

Hepatitis C virus (HCV) and Epstein-Barr virus (EBV) have been repeatedly associated with risk of non-Hodgkin's lymphoma (NHL) in studies focusing on serological evidence of infection. We investigated NHL risk in association with detection of HCV-RNA or EBV-DNA in the peripheral blood mononuclear cells (PBMC). The study involved 91 NHL cases and 182 controls nested in the Italian branch of the EPIC (European Prospective Investigation of Cancer and nutrition) cohort, which obtained blood samples from 47,749 healthy volunteers between 1993 and 1998 in 5 Italian cities. NHL cases were identified until June 2005 through linkage with records of the Cancer, Mortality, and Hospital Discharge Registries. For all study subjects, we performed viral genome analyses on DNA and RNA extracted from buffy-coats and analysed EBV and HCV antibodies. The odds ratios (ORs) of NHL were 1.2 (95% confidence intervals: 0.4-3.8; 5 exposed cases) for PBMC HCV infection and 1.2 (0.7-2.3; 24 exposed cases) for PBMC EBV infection. Similar OR estimates were found for detection of EBV and HCV antibodies. These null results, although based on a relatively small sample size, suggest that persistent EBV and HCV infection in the PBMC is not a stronger predictor of NHL risk than serological evidence of infection.

Is chronic hepatitis C virus infection a risk factor for breast cancer?

AIM: To evaluate the prevalence of breast tumors in adult females with chronic hepatitis C virus (HCV) infection.

METHODS: Prospective, single-center study, based on female outpatients consulting in a liver unit, for 1 year. The study group included females with present and/or past history of chronic infection by HCV. Patients with spontaneous recovery were excluded. Chronic hepatitis had been proved by liver biopsy in the majority of cases and/or biological markers of inflammation and fibrosis. The control group included female patients with other well documented chronic liver diseases: chronic hepatitis B, alcoholic liver disease, autoimmune hepatitis, hemochromatosis, non alcoholic liver disease, chronic cholangitis. Participating patients were prospectively questioned during consultation about past breast history and follow-up by mammography.

RESULTS: Breast carcinoma was recorded in 17/294 patients with HCV infection (5.8%, 95% CI: 3.1-8.4) vs 5/107 control patients (4.7%, 95% CI: 0.67-8.67). Benign tumors of the breast (mastosis, nodules, cysts) were recorded in 75/294 patients with HCV infection (25.5%, 95% CI: 20.5-30.5) vs 21/107 (19.6%, 95% CI: 12.1-27.1) in the control group. No lesion was noted in 202 patients with HCV (68.7%, 95% CI: 63.4-74) vs 81 control patients (75.7%, 95% CI: 67.6-83.8). Despite a trend to an increased prevalence in the group with HCV infection, the difference was not significant compared to the control group (P = NS). In patients over 40 years, the results were, respectively, as follows: breast cancer associated with HCV: 17/266 patients (6.3%, 95% CI: 3.4-9.3) vs 5/95 patients (5.2%, 95% CI: 0.7-9.7) in the control group; benign breast tumors: 72/266 patients with HCV infection (27%, 95% CI: 21.7-32.4) vs 18/95 patients (18.9%, 95% CI: 11-26.8) in the control group; no breast lesion 177/266 (66.5%, 95% CI: 60.9-72.2) in patients with HCV infection vs 72/95 (75.7%, 95% CI: 67.1-84.4) in the control group. The differences were not significant (P = NS).

CONCLUSION: These results suggest that chronic HCV infection is not a strong promoter of breast carcinoma in adult females of any age.

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.

Hepatitis B virus infection and risk of non-Hodgkin lymphoma in South Korea: a cohort study

BACKGROUND

Hepatitis B virus (HBV) infection is common throughout Asia and Africa. Whether chronic HBV infection increases risk of non-Hodgkin lymphoma (NHL) is unclear. We aimed to assess the association between chronic HBV infection and subsequent development of NHL in a South Korean cohort.

METHODS

The Korean Cancer Prevention Study is a cohort study of South Korean workers and their dependants enrolled during 1992-95. From this cohort, we excluded individuals who died before Jan 1, 1993, who had cancer at or before the initial visit, who had missing information about weight, height, alanine aminotransferase or aspartate aminotransferase concentrations, or alcohol use, or who had evidence of HIV or HCV infection. Of 1,284,586 eligible participants, 603,585 had baseline data for serum hepatitis B surface antigen (HBsAg) status and were included in our study. We regarded HBsAg positivity at baseline as evidence of chronic HBV infection. Participants were followed up from baseline until Dec 31, 2006. We used national databases of inpatient and outpatient diagnoses and mortality records to ascertain occurrence of haematological malignancies. We assessed incidence of NHL overall and of NHL subtypes, malignant immunoproliferation, Hodgkin's lymphoma, multiple myeloma, and various leukaemias. We used Cox regression to evaluate associations with HBsAg status, adjusting for sex, age, and enrolment year.

FINDINGS

53,045 (9%) of 603,585 participants tested positive for HBsAg at baseline. Subsequently, 133 HBsAg-positive and 905 HBsAg-negative individuals developed NHL. HBsAg-positive participants had an increased risk of NHL overall compared with those who were HBsAg-negative (incidence 19.4 vs 12.3 per 100,000 person-years; hazard ratio [HR] 1.74, 95% CI 1.45-2.09, adjusted for sex, age at baseline, and enrolment year). Among NHL subtypes, HBsAg positivity was associated with increased risk of diffuse large B-cell lymphoma (n=325, incidence 6.86 vs 3.79 per 100,000 person-years; adjusted HR 2.01, 1.48-2.75) and other or unknown subtypes (n=591, incidence 10.5 vs 7.07 per 100,000 person-years; adjusted HR 1.65, 1.29-2.11), compared with HBsAg negativity. Increased risk was also recorded for malignant immunoproliferation (n=14, incidence 0.44 vs 0.15 per 100,000 person-years; adjusted HR 3.79, 1.05-13.7). Risk of these malignancies was consistently raised in HBsAg-positive participants throughout 14 years of follow-up. HBsAg positivity was not associated with follicular or T-cell NHL, Hodgkin's lymphoma, multiple myeloma, or various leukaemias.

INTERPRETATION

During extended follow-up, HBsAg-positive individuals had an increased risk of NHL, suggesting that chronic HBV infection promotes lymphomagenesis.

FUNDING

Korean Seoul City Research and the National Research and Development Program for Cancer Control, Ministry for Health, Welfare and Family Affairs, Republic of Korea; US National Cancer Institute.

Increased risk for lymphoid and myeloid neoplasms in elderly solid-organ transplant recipients

BACKGROUND

By assessing the spectrum of hematologic malignancies associated with solid-organ transplantation in the elderly, we provide information on the pathogenesis of lymphoid and myeloid neoplasms and the clinical manifestations of immunosuppression.

METHODS

Using data from the U.S. Surveillance, Epidemiology, and End Results Medicare database, we identified 83,016 cases with a hematologic malignancy (age 66-99 years) and 166,057 population-based controls matched to cases by age, sex, and calendar year. Medicare claims were used to identify a history of solid-organ transplantation. We used polytomous logistic regression to calculate odds ratios (OR) comparing transplantation history among cases with various hematologic malignancy subtypes and controls, adjusting for the matching factors and race.

RESULTS

A prior solid-organ transplant was identified in 216 (0.26%) cases and 204 (0.12%) controls. Transplantation was associated with increased risk for non-Hodgkin lymphomas [OR, 2.13; 95% confidence interval (95% CI), 1.67-2.72], especially diffuse large B-cell lymphoma (OR, 3.29; 95% CI, 2.28-4.76), marginal zone lymphoma (OR, 2.48; 95% CI, 1.17-5.22), lymphoplasmacytic lymphoma (OR, 3.32; 95% CI, 1.41-7.81), and T-cell lymphoma (OR, 3.07; 95% CI, 1.56-6.06). Transplantation was also associated with elevated risk of Hodgkin lymphoma (OR, 2.53; 95% CI, 1.01-6.35) and plasma cell neoplasms (OR, 1.91; 95% CI, 1.24-2.93). Risks for myeloid neoplasms were also elevated (OR, 1.99; 95% CI, 1.41-2.81).

CONCLUSION

Solid-organ transplantation is associated with a wide spectrum of hematologic malignancies in the elderly. Risk was increased for four specific non-Hodgkin lymphoma subtypes for which a viral agent has been implicated, supporting an added role for immunosuppression.

IMPACT

Our results support monitoring for a wide spectrum of hematologic malignancies following solid-organ transplant.

Hepatitis C virus infection and lymphoma

Apart from its well known role as an etiological agent for non-A and non-B viral hepatitis, there is growing evidence that hepatitis C virus is associated to B-cell non-Hodgkin lymphoma. The association between HCV and lymphoproliferative disorders has been recently postulated based on epidemiological data, biological studies and clinical observations. Although various subtypes of lymphomas appear to be associated to HCV, diffuse large B-cell lymphoma, small lymphocytic lymphoma/chronic lymphocytic leukemia and marginal zone lymphoma appeared to be particularly represented among HCV-positive patients. The causative role of HCV in those disorders has been further supported by the response to antiviral therapy. Despite a better understanding of pathophysiological processes at stake leading from HCV infection to overt lymphoma, many issues still need to be further elucidated. Although HCV has been demonstrated to directly infect peripheral blood mononuclear cells both in vitro and, in some cases, in vivo, a strong body of evidence rather supports the hypothesis of an indirect transformation mechanism by which sustained antigenic stimulation leads from oligoclonal to monoclonal expansion and sometimes to lymphoma, probably through secondary oncogenic events. Here, we review epidemiological and biological studies, as well as clinical data on antiviral therapy, linking HCV-infection to B-cell non-Hodgkin lymphoma.

Risk for renal cell carcinoma in chronic hepatitis C infection

BACKGROUND

Chronic infection with hepatitis C virus (HCV) confers increased risk for chronic renal disease, and numerous reports suggest an association with renal cell carcinoma (RCC), a cancer with rapidly rising global incidence. We sought to determine whether HCV infection confers an increased risk for developing RCC.

METHODS

With the use of administrative data from a large, integrated, and ethnically diverse healthcare system, we did a cohort study of 67,063 HCV-tested patients between 1997 and 2006 who were followed for the development of RCC until April 2008.

RESULTS

A search of the health system cancer registry for patients with the diagnosis of kidney cancer showed that RCC was diagnosed in 0.6% (17 of 3,057) of HCV-positive patients versus 0.3% (177 of 64,006) of HCV-negative patients. The mean age at RCC diagnosis was much younger in HCV-positive individuals (54 versus 63; P < 0.001). The univariate hazard ratio for RCC among HCV patients was 2.20 (95% confidence interval, 1.32-3.67; P = 0.0025). In a multivariate model that included the risk factors age, African-American race, male gender, and chronic kidney disease, the overall hazard ratio for RCC among HCV patients was 1.77 (95% confidence interval, 1.05-2.98; P = 0.0313).

CONCLUSION

Chronic HCV infection confers a risk for the development of RCC.

IMPACT

Clinicians should consider newly identified renal lesions in patients with chronic HCV infection with a heightened suspicion for neoplasm, and newly diagnosed cases of RCC may require more careful surveillance for the presence of HCV infection. Additional studies are required to confirm these findings and to explore potential mechanisms of oncogenesis.

Differential characteristics of Waldenström macroglobulinemia according to patterns of familial aggregation

Familial aggregation of Waldenström macroglobulinemia (WM) and related B-cell disorders (BCDs) suggests a role for genetic factors, but few data address environmental influences. We designed a questionnaire-based study to examine clinical and environmental factors in a cohort of WM families with various patterns of case aggregation. We analyzed data on 103 WM patients and 272 unaffected relatives from 35 multiple-case WM and 46 mixed WM/BCD kindred and 28 nonfamilial (sporadic) WM patients, using logistic regression models with generalized estimating equations to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for association. In this study population, the WM disease process appeared similar among patients regardless of family history. Familial WM patients were more likely than unaffected relatives to report a history of autoimmune disease (OR, 2.27; 95% CI = 1.21-4.28) and infections (OR, 2.13; 95% CI = 1.25-3.64). Familial WM patients were also more likely to report exposure to farming (OR, 2.70; 95% CI = 1.34-5.42), pesticides (OR, 2.83; 95% CI = 1.56-5.11), wood dust (OR, 2.86; 95% CI = 1.54-5.33), and organic solvents (multiple-case WM OR, 4.21; 95% CI = 1.69-10.51) compared with unaffected family members. These data provide clues to both genetic and environmental factors that may influence development of WM. Well-designed case-control studies are needed to confirm these findings.

Immune-related and inflammatory conditions and risk of lymphoplasmacytic lymphoma or Waldenstrom macroglobulinemia

BACKGROUND

Chronic immune stimulation appears to be associated with lymphoplasmacytic lymphoma (LPL)-Waldenström macroglobulinemia (WM); however, available information is sparse. We conducted, to our knowledge, the most comprehensive study to date to evaluate associations between a personal or family history of many immune-related and/or inflammatory disorders and the subsequent risk of LPL-WM.

METHODS

We used Swedish population-based registries to identify 2470 case patients with LPL-WM, 9698 matched control subjects, and almost 30 000 first-degree relatives of either case patients or control subjects. We evaluated a wide range of autoimmune, infectious, allergic, and inflammatory conditions. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) for each condition by use of logistic regression.

RESULTS

An increased risk of LPL-WM was associated with a personal history of the following autoimmune diseases: systemic sclerosis (OR = 4.7, 95% CI = 1.4 to 15.3), Sjögren syndrome (OR = 12.1, 95% CI = 3.3 to 45.0), autoimmune hemolytic anemia (OR = 24.2, 95% CI = 5.4 to 108.2), polymyalgia rheumatica (OR = 2.9, 95% CI = 1.6 to 5.2), and giant cell arteritis (OR = 8.3, 95% CI = 2.1 to 33.1). An increased risk of LPL-WM was associated with a personal history of the following infectious diseases: pneumonia (OR = 1.4, 95% CI = 1.1 to 1.7), septicemia (OR = 2.4, 95% CI = 1.2 to 4.3), pyelonephritis (OR = 1.7, 95% CI = 1.1 to 2.5), sinusitis (OR = 2.7, 95% CI = 1.4 to 4.9), herpes zoster (OR = 3.4, 95% CI = 2.0 to 5.6), and influenza (OR = 2.9, 95% CI = 1.7 to 5.0). An increased risk of LPL-WM was associated with a family history of the following autoimmune or infectious diseases: Sjögren syndrome (OR = 5.0, 95% CI = 2.1 to 12.0), autoimmune hemolytic anemia (OR = 3.8, 95% CI = 1.1 to 13.2), Guillain-Barré syndrome (OR = 4.1, 95% CI = 1.8 to 9.4), cytomegalovirus (OR = 2.7, 95% CI = 1.4 to 5.3), gingivitis and periodontitis (OR = 1.9, 95% CI = 1.3 to 2.7), and chronic prostatitis (OR = 4.3, 95% CI = 1.7 to 11.1).

CONCLUSIONS

Personal history of certain immune-related and/or infectious conditions was strongly associated with increased risk of LPL-WM. The association of both personal and family history of Sjögren syndrome and autoimmune hemolytic anemia with risk of LPL-WM indicates the potential for shared susceptibility for these conditions.

Hepatitis C progressing to hepatocellular carcinoma: the HCV dialysis patient in dilemma

Approximately 3.2 million people in the United States have chronic hepatitis C virus (HCV) infection; the primary cause for adult liver transplantation and a significant burden on healthcare resources. The role of HCV and other risk factors in development of HCC in patients with chronic kidney disease is not well defined. We studied predictors of hepatocellular carcinoma (HCC) in dialysis patients with chronic HCV by analyzing factors associated with its development. Data were extracted from the United States Renal Database System (USRDS) using ICD-9 codes. Variables included were gender, race, duration on dialysis and co-morbidities (alcohol abuse, drug abuse, HIV, hepatitis B, diabetes and/or presence of cirrhosis). Among the 32 806 HCV infected subjects, 262 cases had HCC. HCC was 12 times more likely in subjects with cirrhosis (P < 0.001), three times more likely in subjects with alcohol abuse (P < 0.001), and 1.3 times more likely in subjects with diabetes (P = 0.04). Asians were three times more likely (P < 0.001) to have HCC. Females were less likely to have HCC compared to males (P = 0.002). The likelihood of having HCC increased with age (P =0.001). This population-based study demonstrates that among subjects with HCV on dialysis, those with cirrhosis, Asian race and history of alcohol abuse are at highest risk for development of HCC. Furthermore, these findings indicate links between HCV and HCC which are valuable in case management for identifying; monitoring, and managing dialysis patients with HCC.

CXCL10 and CCL2 chemokine serum levels in patients with hepatitis C associated with autoimmune thyroiditis

To evaluate CXCL10 and CCL2 in patients with hepatitis C virus chronic infection in presence/absence of autoimmune thyroiditis (AT). CXCL10 was significantly higher in: (1) patients with AT than controls without AT (control 1) (P < 0.001; ANOVA); (2) patients with hepatitis C infection than control 1 and patients with AT (P < 0.001); (3) patients with hepatitis C virus chronic infection and AT (HCV+AT) than control 1 and patients with AT (P < 0.001) and hepatitis C (P = 0.004). By defining a high CXCL10 level as a value >218 pg/mL, 2% of control 1, 14% of patients with AT, 68% of patients with hepatitis C infection, 81% of HCV+AT had high CXCL10 (P < 0.0001; chi-square). CCL2 was similar in control 1 and patients with AT. CCL2 was significantly higher in: (1) patients with hepatitis C infection than control 1 (P = 0.04; ANOVA); (2) HCV+AT than patients with AT (P = 0.03) and control 1 (P = 0.02); no difference was observed between HCV with or without AT. Our study demonstrates: (1) higher circulating CXCL10 and CCL2 in patients with hepatitis C virus chronic infection than in controls; (2) higher CXCL10 in HCV+AT than in patients with hepatitis C infection, suggesting a stronger Th1 immune response in these patients.

Vitamin D and non-Hodgkin lymphoma risk in adults: a review

Animal and human studies support a protective effect of vitamin D sufficiency related to malignancy by uncovering paracrine and autocrine effects of extra-renal 25-hydroxyvitamin D (25(OH)D) activation including regulation of cell cycle proliferation, apoptosis induction, and increased cell differentiation signaling. Recent epidemiologic studies demonstrate a reduction in non-Hodgkin lymphoma (NHL) risk with increased sunlight exposure. As sunlight is a major vitamin D source, it has been suggested that vitamin D status may mediate this observed association. This review provides a comprehensive discussion of the current epidemiologic evidence with regard to the investigation of an association between vitamin D status and NHL risk.

Engagement of CD81 induces ezrin tyrosine phosphorylation and its cellular redistribution with filamentous actin

CD81 is a tetraspanin family member involved in diverse cellular interactions in the immune and nervous systems and in cell fusion events. However, the mechanism of action of CD81 and of other tetraspanins has not been defined. We reasoned that identifying signaling molecules downstream of CD81 would provide mechanistic clues. We engaged CD81 on the surface of B-lymphocytes and identified the induced tyrosine-phosphorylated proteins by mass spectrometry. This analysis showed that the most prominent tyrosine phosphorylated protein was ezrin, an actin-binding protein and a member of the ezrin-radixin-moesin family. We also found that CD81 engagement induces spleen tyrosine kinase (Syk) and that Syk was involved in tyrosine phosphorylation of ezrin. After engagement of CD81, it colocalized with ezrin and F-actin, and this association was disrupted when Syk activation was blocked. Taken together, these studies suggest a model in which CD81 interfaces between the plasma membrane and the cytoskeleton by activating Syk, mobilizing ezrin, and recruiting F-actin to facilitate cytoskeletal reorganization and cell signaling. This mechanism might explain the pleiotropic effects induced in response to stimulation of cells by anti-CD81 antibodies or by the hepatitis C virus, which uses this molecule as its key receptor.

Hepatitis C and lymphoproliferative disorders: from mixed cryoglobulinemia to non-Hodgkin's lymphoma

BACKGROUND & AIMS

Hepatitis C virus is associated with both mixed cryoglobulinemia and non-Hodgkin's lymphoma, particularly B-cell non-Hodgkin's Lymphoma. Although there are geographic discrepancies in the incidence and prevalence of hepatitis C virus-related lymphomas, large epidemiologic studies and meta-analyses confirm this relationship in both patients with and without mixed cryoglobulinemia. Other factors such as gene translocation, somatic hypermutation and direct infection may also play a role in the malignant transformation of B-cells.

METHODS

Recent advances in our understanding between the complex relationship between hepatitis C virus and its interactions with cell proteins on B-cell surface membranes has led to proposed mechanisms on how hepatitis C virus leads to chronic antigenic stimulation resulting in lymphoproliferation.

RESULTS

Hepatitis C virus is more weakly associated with T-cell lymphomas, Waldenstrom's macroglobulinemia and other monoclonal gammopathies. Remission of mixed cryoglobulinemia is strongly associated with reduction of hepatitis C virus viral load and recurrence of disease corresponds with viral relapse. Similarly, some studies have shown complete remissions of low grade lymphomas with sustained viral response after antiviral therapy for hepatitis C virus.

CONCLUSIONS

Further studies are needed to more clearly understand the pathogenesis and management of hepatitis C virus-related lymphoproliferative disorders.

Hepatitis C virus-induced cryoglobulinemia

In this review we discuss the clinical manifestations, pathogenesis, and treatment of hepatitis C virus (HCV)-related cryoglobulinemia. HCV is a major cause of liver-related morbidity and is increasingly recognized as an instigator of B-cell lymphoproliferative disorders such as mixed cryoglobulinemia and non-Hodgkin lymphoma. Cryoglobulinemia is characterized by the clonal expansion of rheumatoid factor-expressing B cells in the liver, lymph nodes, and peripheral blood, resulting in the presence of cryoglobulins in the circulation. Cryoglobulins are cold-insoluble immune complexes containing rheumatoid factor, polyclonal IgG, and HCV RNA that precipitate and deposit on vascular endothelium, causing vasculitis in organs such as the skin, kidneys, and peripheral nerves. A subset of patients develops a low-grade lymphoma composed of B cells that are immunophenotypically similar to the expanded B cells seen in cryoglobulinemia. HCV-related B-cell lymphoproliferative disorders likely comprise a spectrum of disease, ranging from asymptomatic clonal B-cell expansions to pathogenic cryoglobulinemia and lymphoma. It is unclear how B cells become dysregulated during the course of chronic HCV infection, and continued patient-centered research is necessary to elucidate the pathogenesis of HCV-related B-cell dysregulation.

Genetic and immune-related factors in the pathogenesis of lymphoproliferative and plasma cell malignancies

There are data to support a role for genetic and immune-related factors in the pathogenesis of lymphomas and plasma cell diseases. In this paper, we review our published large population-based studies and other relevant studies in Hodgkin's and non-Hodgkin's lymphomas, multiple myeloma, and the precursor condition monoclonal gammopathy of undetermined significance. We discuss the overlap in risk factors between related malignancies and explore the underlying mechanisms. Based on these studies, we provide clinical implications and discuss the relevance of these data for patient counseling and clinical follow-up. Finally, we suggest future directions for new studies designed to increase our current knowledge and to define underlying biological mechanisms of our findings.

Novel aspects pertaining to the relationship of Waldenström's macroglobulinemia, IgM monoclonal gammopathy of undetermined significance, polyclonal gammopathy, and hypoglobulinemia

Waldenström's macroglobulinemia (WM) is associated with a precursor condition, monoclonal gammopathy of undetermined significance (MGUS) of immunoglobulin-M (IgM) type. The etiology of these conditions is unknown. Recent studies at the population level have provided new data regarding familial aggregation of these disorders and other B-cell malignancies. Studies of familial clusters of WM have demonstrated an increased frequency of IgM MGUS compared with the general population and have provided new data suggesting that the phenotypic spectrum might also include polyclonal gammopathy and hypoglobulinemia. While the preponderance of immunoglobulin abnormalities in relatives of WM cases involves IgM, other immunoglobulin types (IgG and IgA) might also be affected. Large collaborative studies are needed to confirm these findings, which present an opportunity to define the earliest lesion(s) in the WM oncogenic pathway.

Acute leukemia, a rare but fatal complication after liver transplantation

Little information is available about the risk factors and means to improve the survival rate of acute leukemia in a rare but often fatal complication after liver transplantation (LT). We report the development of AML-M2 in one of the 764 patients who underwent liver transplantation at our center, and review the literature on similar cases. The patient, a 42-year-old man who developed acute leukemia 38 months after liver transplantation, was successfully treated with chemotherapy and has subsequently been in remission. With appropriate adjustment of immunosuppressive agents, he was able to safely benefit from chemotherapy. Only 16 patients with acute leukemia after liver transplantation have been reported, and the mortality rate is extraordinarily high (52.94%, 9/17). More cases of acute leukemia will emerge as the rate of survival after liver transplantation increases. The patient's chromosomal mutation profile, the choice of immunosuppressive agent, and infection by hepatitis virus may be the risk factors for the development of acute leukemia after LT. Our experience suggests that clinicians should adjust the immunosuppressive agents according to the immunosuppressive state of the patient and explore the option of reducing or stopping the medication as long as liver function remains stable. These measures could help reduce the high mortality rate among these patients.

Endocrine manifestations of hepatitis C virus infection

Chronic infection with hepatitis C virus (HCV) can result in both hepatic and extrahepatic disease and endocrine dysfunction represents an important class of HCV-related extrahepatic disease. The most frequently occurring--and clinically important--of these endocrine disorders are thyroid disease and type 2 diabetes mellitus. In this Review, we evaluate the evidence in support of a link between HCV infection and endocrine-system dysfunction, and discuss potential pathophysiological mechanisms. A meta-analysis of the literature has revealed significant associations between chronic HCV infection, thyroid autoimmunity and hypothyroidism. Furthermore, a high prevalence of thyroid cancer has been reported in HCV-positive patients. Several clinicoepidemiological studies have demonstrated that chronic HCV infection could lead to the development of type 2 diabetes mellitus, possibly as a result of HCV-induced metabolic disturbances. Some researchers have postulated that a type 1 T-helper -cell mediated immune response underpins the association of chronic HCV infection with endocrine disease. Indeed, the available data suggest that a common immunological, type 1 T-helper cell pattern of cytokine expression and activation (via interferon-gamma) could provide the pathophysiological basis for this association. Nonetheless, additional studies will be necessary to elucidate fully all the mechanisms involved in HCV-related endocrine dysfunction.