Subtypes of Epstein-Barr virus (EBV) in Hodgkin's disease: association between B-type EBV and immunocompromise [see comments]

Epstein-Barr virus (EBV) has been associated with Hodgkin's disease (HD) in up to 50% of cases, but the subtype of EBV involved has only recently been studied. In this report, biopsy samples from 30 patients with HD were assessed for EBV sequences using both the polymerase chain reaction (PCR) and in situ hybridization (ISH). EBV sequences were localized to the malignant Reed-Sternberg cells and their mononuclear variants (Hodgkin's cells) in 9 of the 30 cases, with 7 demonstrating A- type and 2 B-type EBV sequences. Both of the patients with B-type EBV- associated HD had features to suggest pre-existing immune compromise: one was infected with human immunodeficiency virus (HIV) and had severe CD4+ T-lymphocyte depletion; the other was a debilitated elderly patient with dementia. A previous study suggested that A-type EBV alone is associated with HD and the finding of predominantly A-type EBV in the present series is in keeping with this report. The presence of B- type EBV in the HD of patients with pre-existing immunodeficiency, taken together with the recent report that B-type EBV occurs in HIV- associated non-Hodgkin's lymphoma, suggests that B-type EBV may be an important human pathogen in immunocompromised patients.     

Expression of B-type Epstein-Barr virus in HIV-infected patients and cardiac transplant recipients.

In the present study, peripheral blood mononuclear cells (PBMCs) were obtained from HIV+ subjects as well as cardiac transplant recipients, and the presence of A- and B-type Epstein-Barr virus (EBV) was determined using the polymerase chain reaction (PCR). Of the HIV+ patients studied, 24% were found to be infected with A-type EBV, 27% with B-type EBV, and 39% with both A and B virus types. Analysis of PBMCs from cardiac transplant recipients revealed that 39% were infected with A-type EBV, 33% with B-type EBV, and 28% with both EBV types. These results demonstrate a higher prevalence of infection with B-type EBV in HIV+ patients, than had been found previously by an analysis of spontaneously generated lymphoblastoid cell lines. The data indicated that it is not HIV per se which is responsible for the high incidence of B-type EBV in HIV+ individuals.     

High incidence of Kaposi sarcoma-associated herpesvirus-related non-Hodgkin lymphoma in patients with HIV infection and multicentric Castleman disease

Multicentric Castleman disease (MCD) is a distinct type of lymphoproliferative disorder associated with inflammatory symptoms and interleukin 6 (IL-6) dysregulation. In the context of human immunodeficiency virus (HIV) infection, MCD is associated with Kaposi sarcoma-associated herpesvirus, also called human herpesvirus type 8 (KSHV/HHV8). Within a prospective cohort study on 60 HIV-infected patients with MCD, and a median follow-up period of 20 months, 14 patients developed KSHV/HHV8-associated non-Hodgkin lymphoma (NHL): 3 "classic" KSHV/HHV8(+) Epstein-Barr virus-positive (EBV(+)) primary effusion lymphoma (PEL), 5 KSHV/HHV8(+) EBV(-) visceral large cell NHL with a PEL-like phenotype, and 6 plasmablastic lymphoma/leukemia (3/3 KSHV/HHV8(+) EBV(-)). The NHL incidence observed in this cohort study (101/1000 patient-years) is about 15-fold what is expected in the general HIV(+) population. MCD-associated KSHV/HHV8(+) NHL fell into 2 groups, suggesting different pathogenesis. The plasmablastic NHL likely represents the expansion of plasmablastic microlymphoma from the MCD lesion and progression toward aggressive NHL. In contrast, the PEL and PEL-like NHL may implicate a different original infected cell whose growth is promoted by the cytokine-rich environment of the MCD lesions.     

Characteristics of patients with systemic lupus erythematosus (SLE) and non-Hodgkin’s lymphoma (NHL)

Patients with systemic lupus erythematosus (SLE) are at increased risk of developing non-Hodgkin’s lymphoma (NHL), but features of SLE associated with NHL are not well described. The objective of this study was to describe SLE characteristics, laboratory serologies, and medication histories in patients who subsequently develop NHL. Two thousand twenty patients with SLE were identified using the online Partners’ patient database research tool between October 1992 and June 2005. We confirmed the diagnoses of SLE and NHL and sought details of medical history and treatment by medical record review. Eleven patients with NHL without coexisting rheumatoid arthritis, Sjögren’s, or HIV were identified; seven of these (64%) had a diffuse large B cell lymphoma subtype, and 83% of those stained were Epstein–Barr virus (EBV) negative. The mean duration of SLE at NHL diagnosis was 17.8 years (range 1.6–41.8), and the mean Systemic Lupus International Collaborative Clinics/American College of Rheumatology damage index was 1.9. Seven patients (64%) had SLE hematologic involvement, four had anti-dsDNA antibodies, and four had anti-phospholipid antibodies. One patient had significant renal disease. All patients had arthritis and had received antimalarial therapy. Five of 11 patients had received other treatments for SLE, including cyclophosphamide, imuran, methotrexate, and/or sulfasalazine. Diffuse large B cell lymphoma was the most common subtype of NHL, and most were EBV negative. Although disease duration was fairly long and end organ damage moderately severe in this group of patients, renal disease and the use of immunosuppressive chemotherapeutic agents were rare and did not appear to confer an increased risk of NHL development.     

The prevalence of hepatitis C and hepatitis G virus infection in patients with B cell non-Hodgkin lymphomas in Greece: a Hellenic Cooperative Oncology Group Study

Our aim was to investigate the association between chronic hepatitis C virus (HCV) infection and B cell non-Hodgkin lymphoma (NHL) in the Greek population. We studied 120 patients (70 men and 50 women, mean age 59 years) diagnosed with NHL. One hundred and eight had B cell NHL (90%) and 12 had T cell NHL (10%). The presence of anti-HCV antibodies in patients and controls was investigated using the monoclonal enzymatic immunoassay (MEIA) method. The detection of HCV RNA and hepatitis G virus (HGV) RNA in patients with B cell NHL and anti-HCV-positive controls was performed using an RT-PCR technique. Anti-HCV antibodies were present in only 2 of the 108 patients with B cell NHL (1.9%), while the prevalence of HCV infection in the healthy population was 0.6%, and in patients with various solid tumors treated with chemotherapy, it was 0.99%. Ten of the 108 B cell NHL patients (9.26%) were diagnosed as HGV RNA positive, while the prevalence of HGV infection in 285 Greek blood donors was 0.7%. Our findings do not confirm a strong association between HCV infection and B cell NHL for Greek patients. The increased prevalence of HGV infection detected in patients with NHL could imply the potential participation of HGV in the pathogenesis of NHL.     

B-cell acute lymphocytic leukemia in HIV-antibody-positive patients

B-cell non-Hodgkin lymphoma (NHL) has been well described in association with human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome (AIDS). Many of these lymphomas are of the diffuse, aggressive, subtype B-cell NHL, including Burkitt and Burkitt-like lymphoma. Recently, there have been reports of B-cell acute lymphocytic leukemia (ALL), Burkitt type, in patients who were either HIV antibody-positive or at high risk for AIDS. We have seen three cases of B-cell ALL, Burkitt type, and herein describe their clinical and laboratory characteristics. All patients were HIV antibody-positive. Since stage IV Burkitt lymphoma in blood phase and B-cell ALL, Burkitt type, represent a continuum of the same disease, and since it is also an aggressive B-cell malignancy, we suggest that B-cell ALL, Burkitt type, in HIV antibody-positive patients should support the diagnosis of AIDS.     

Immunodeficiency and its relation to lymphoid and other malignancies

 The reasons why immunodeficiency leads to malignant disorders are multifactorial. The overall incidence of malignancies in persons infected with the human deficiency virus (HIV) is estimated to be 40%. Other infecting agents, especially herpesvirus species, play a pivotal role in HIV-associated non-Hodgkin's lymphoma (NHL) and Kaposi's sarcoma (KS). Mucosaassociated lymphatic tissue (MALT) lymphoma in the stomach may be a result of a chronic gastritis caused by Helicobacter pylori, a gram-negative bacterium. The Epstein-Barr virus (EBV) genome can be found in a high percentage of lymphoma cells of HIV-NHL (nearly 100% in the primary lymphoma of the CNS and about 50% in all other lymphoma entities). In body-cavity based NHL, characterized by the absence of EBV and c-myc oncogen, sequences of a herpesvirus were identified which corresponds to the gamma-herpes viremia found in KS. The Kaposi's sarcoma-associated herpesvirus (KSHV) was usually present in primary-effusion lymphoma (PEL). HIV-infection, which causes multiple dysfunctions within the immune system, triggers the cytokine dysregulation. An abnormal endogenous interferon (IFN)-alpha production is observed in HIV-infected patients with KS, especially in the later natural course of the disease. A monitoring of the IFN-system by MxA, a protein specifically induced by IFN's of type I, may be a necessary stratum of identifying patients who show superior effects and the greatest clinical benefit from treatment with IFN-alpha. Received: 22 April 1996 / Accepted: 18 June 1996     

EBV-induced human B cell lymphomas in hu-PBL-SCID mice.

Epstein-Barr virus (EBV) infection is associated with Burkitt's lymphoma (BL) in normal individuals and immunoblastic B cell lymphomas in immunosuppressed or HIV-infected individuals. SCID mice reconstituted with human peripheral blood leukocytes (hu-PBL-SCID) from EBV-seropositive donors also may develop spontaneous B cell lymphomas which histologically and phenotypically resemble post-transplant tumors, and are distinct from BL. These tumors always contain EBV DNA. We have noted three different reproducible outcomes depending upon the EBV-seropositive donor used for generation of hu-PBL-SCID mice: (i) no tumors appear; (ii) tumors appear in a fraction of hu-PBL-SCID mice with a 10-20 wk. latent period; or (iii) tumors appear in all hu-PBL-SCID mice within 6-10 wk. Southern blot analysis of late versus early tumors using a probe specific for the EBV terminal repeat sequences (BamNJ), which allows distinction between circular latent and linear replicating genomes, shows that late tumors do not involve active EBV replication but that early tumors do show replicating genomes. In addition, EBV genomes were monoclonal in late tumors but polyclonal in early tumors. These data suggest two mechanisms for EBV lymphomagenesis, slow outgrowth of rare latently-infected B cells, and more rapid transformation of uninfected bystander B cells by replicating virus. The latter process may be highly amenable to therapy in patients at risk for EBV-related lymphomas. In addition, prospective screening of EBV-seropositive transplant recipients in the hu-PBL-SCID model may predict the risk of post-transplant lymphoma development.     

Coinfection with A- and B-type Epstein-Barr virus in human immunodeficiency virus-positive subjects

A possible cofactor in human immunodeficiency virus (HIV) infection is the Epstein-Barr virus (EBV), which is divided into two primary types that differ significantly in their transformation efficiency. The B-type EBV cell line is much more difficult to establish than the A-type. The extent of systemic B-type EBV infection was assessed in HIV-positive subjects and controls. Lymphoblastoid cell lines were established from 26 HIV-positive subjects and analyzed for the presence of A- or B-type EBV by Southern analysis and immunoblotting. Some 19% of HIV-positive persons were infected with B-type EBV, 69% with A-type, and 12% with both types. Analysis of the individual strains of EBV harbored by the HIV-positive subjects showed that HIV-induced immunosuppression had not led to increased susceptibility to repeated EBV infections. However, the occurrence of B-type infection in HIV-positive subjects was sixfold higher than that in the general community, indicating that HIV-induced immunodeficiency or HIV itself specifically enhanced the expression of the B-type EBV.     

Definition of two distinct types of AIDS-associated non-Hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) in a human immunodeficiency virus (HIV)-infected person is an AIDS-defining condition. There is both an increased incidence of NHL and a poorer prognosis for the disease in these HIV-infected persons, compared with patients who spontaneously develop NHL. A series of 41 consecutive patients with HIV-associated NHL treated at St Vincent's Hospital, Sydney, between 1984 and September 1989 was assessed. Of these, 36 had NHL proven on biopsy and NHL was diagnosed clinically in the other five. On histologic examination 11 had high-grade malignant lymphoma, small non-cleaved cell (SNCC) type, similar to Burkitt lymphoma, 18 had high-grade lymphoma large cell immunoblastic (LCI) type, and seven could not be classified due to inadequate material for assessment. The clinical features of these two groups were compared. Those patients with LCI had advanced CD4+ immunodeficiency and poor survival (median = 6 weeks). The other group with SNCC had better preserved immune function, and longer survival (median = 18 weeks). Three patients had survived longer than 3 years all of whom had SNCC lymphoma as their first AIDS-defining illness. The clinical features and prognostic factors demonstrated in this study document heterogeneity of NHL in HIV-infected patients and should be used as a guide to treatment of these patients, by reserving more intensive treatment for those persons with better prognostic features.     

Prevalence of antibodies to Epstein-Barr virus nuclear antigen 2B in persons infected with the human immunodeficiency virus

We measured the presence of antibodies to the Epstein-Barr virus (EBV) nuclear antigen 2B (EBNA2B) in patients with AIDS and related disorders, persons with human immunodeficiency virus (HIV) infection, persons at risk for HIV infection, and normal persons. Sera from 38% (16 of 43) of the patients with AIDS and 35% (43 of 123) of HIV-positive individuals reacted with EBNA2B, versus 25% (21 of 83) of the high-risk patients and 7.5% (5 of 65) of the normal persons. Screening these sera against cell lines that express EBNA2B, EBNA2A, or neither antigen revealed that only a proportion of these sera contained EBNA2B-specific antibodies. Many sera reacted with both antigens. Of the EBNA2B-specific sera, 14% (6 of 43) were from patients with AIDS, 16% (20 of 123) from HIV-positive individuals, 5% (4 of 83) from high-risk individuals, and 4.5% (3 of 65) from normal persons. The presence of antibodies to the EBNA2B in HIV-infected individuals indicates that they may be infected with type B strains of EBV.     

Syngeneic stem cell transplantation for HIV-related lymphoma

The treatment of human immunodeficiency virus (HIV)-related lymphoma is beset by a number of therapeutic limitations. High-dose chemotherapy followed by peripheral blood stem cell transplantation (PBSCT) for relapsed disease is one option, but may be compromised by unacceptable treatment-related morbidity and mortality. We describe an HIV-positive male with relapsed immunoblastic non-Hodgkin's lymphoma (NHL) who successfully received salvage chemotherapy followed by a syngeneic PBSCT from his HIV-negative (hepatitis C positive) brother. At 15 months post-transplant he remains in complete remission with low-level HIV viral load, an improved CD4 lymphocyte count and absent anti-hepatitis C antibodies. We believe selected patients with relapsed HIV-related NHL should be considered for high-dose therapy.     

Establishment of two Epstein-Barr virus negative Burkitt cell lines from a patient with AIDS and B-cell lymphoma

To analyze the pathogenesis of B-cell lymphomas in patients with acquired immunodeficiency syndrome (AIDS), we studied two cell lines, Es I and Es III, established from one such lymphoma for the presence of sequences of the Epstein-Barr virus (EBV) and the human immunodeficiency virus [HIV; lymphadenopathy-associated virus (LAV/HTLV- III)] as well as for the presence of cytogenetic abnormalities and monoclonal rearrangements of immunoglobulin and T-cell receptor genes. Both cell lines expressed the same IgM, kappa phenotype as the original lymphoma. The karyotype of Es I was 46, XY, t(8;14), 2 p+, inv (6p), 17p-, and the cells of Es III had an additional i(7q). Immunoglobulin gene studies demonstrated the identical monoclonal rearrangements in both cell lines. Neither EBV nor HIV sequences were detectable in the malignant B cells at the genomic level, leading to the conclusion that mechanisms other than transformation by EBV or HIV may have contributed to the B-cell lymphoma in this patient and possibly also to the generally increased frequency in patients with AIDS.     

Epstein–Barr virus (EBV) genotypes among human immunodeficiency virus (HIV)‐related B‐cell Lymphomas and B‐cell post‐transplant lymphoproliferative disorders (B‐PTLD) – late‐onset lymphomas,especially in the HIV setting,are associated with type‐B‐EBV

We investigated 26 B‐cell post‐transplant lymphoproliferative disorders (B‐PTLD) and 15 human immunodeficiency virus‐related aggressive B‐cell lymphomas (HIV‐BCL) from England that were associated with Epstein–Barr virus (EBV) for the polymorphic sequences of the EBV‐encoded nuclear antigen 3C (EBNA3C) gene to distinguish the two different EBV strains. Type‐A‐EBV was identified in 92% of B‐PTLDS and in 53% of HIV‐BCL (P = 0.003). Among HIV‐BCL, patients associated with type‐B‐EBV had been HIV positive for significantly longer when compared to those associated with type‐A (P = 0.037) although there were no correlations with ethnicity, CD4 cell counts or plasma HIV viral load.     

HIV-1 subtype diversity in Minnesota

BACKGROUND: Genetic variation in human immunodeficiency virus (HIV)-1 poses significant public-health and clinical challenges. In North America, subtype B is most prevalent. HIV-1 subtyping is not integrated into routine HIV/acquired immunodeficiency syndrome surveillance in the United States. In 2003, the Minnesota Department of Health piloted HIV-1 subtyping with routine surveillance to describe the existence and variety of non-subtype B strains. METHODS: Targeted HIV-1 subtype surveillance was conducted on 98 African-born HIV-infected patients. Sentinel subtype surveillance was conducted in a Minneapolis sexually transmitted disease clinic on 28 newly diagnosed non-African HIV-positive patients. Subtype determination was based on a partial sequence of the gp41 region of the HIV-1 env gene. RESULTS: Subtyping was successful for 87 of 98 samples from African-born HIV-infected patients; 95% were non-B subtypes. The 7 subtypes observed were consistent with strains endemic in patients' birth regions. Subtyping was also completed for samples from 25 of 28 non-African-born patients; all were subtype B. CONCLUSIONS: Multiple HIV-1 subtypes are present in Minnesota. Our data suggest that most of the HIV cases in Minnesota among African-born patients are non-B subtypes. Population-based surveillance inclusive of groups at high risk for variant strains is needed to monitor the prevalence and variety of HIV subtypes in the United States.     

Elevated expression of activation induced cytidine deaminase in peripheral blood mononuclear cells precedes AIDS-NHL diagnosis

Non-Hodgkin's B cell lymphoma (NHL) is a common cancer in HIV infection. Many NHL are thought to result from errors in class switch recombination and/or somatic hypermutation, processes that occur in germinal center B cells, and require the activity of activation induced cytidine deaminase (AID). Since NHL is a common cancer in HIV infection, and expression of AID could contribute to the development of NHL, we hypothesized that AID expression would be elevated in those who went on to develop AIDS-associated NHL (AIDS-NHL). AID mRNA levels were measured by TaqMan RT-PCR in peripheral blood mononuclear cells, obtained prior to AIDS-NHL diagnosis, from 16 HIV-infected subjects who developed AIDS-NHL, and from control subjects (AIDS but no NHL, and HIV-negative subjects). PBMC AID expression was markedly elevated in those who developed AIDS-NHL, when compared to AIDS and HIV-negative controls. Additionally, AID expression was seen to differ depending on NHL subtype, with the highest levels of expression seen in those who developed Burkitt's lymphoma.     

Circulating Epstein-Barr virus (EBV) in HIV-infected patients and its relation with primary brain lymphoma.

OBJECTIVE: To analyze Epstein-Barr virus (EBV) load at different HIV infection stages and its relation with brain lymphoma. DESIGN: A cross-sectional study was conducted on 172 HIV-infected individuals: 62 asymptomatic HIV carriers (group A), 30 HIV progressors (group B), 73 AIDS patients (group C), seven AIDS patients with brain lymphoma (group C-BL); and 26 blood donors (group BD) as healthy carriers. EBV load was measured in peripheral blood mononuclear cells (PBMC) and plasma samples using a semi-quantitative PCR method. RESULTS: PBMC-EBV levels in HIV-infected patients were higher than in the blood donors (p<0.05). No differences in PBMC-EBV loads were found in groups A, B, or C (p>0.05), while the C-BL group had significantly lower levels (p<0.05). Similar PBMC-EBV loads were seen in HIV-infected patients with CD4+ T cell counts higher than 50/mm(3) (p>0.05), while significantly lower levels were found in cases with less than 50 cells/mm(3) (p<0.05). In all HIV-infected patients, plasma-EBV load was lower than, or similar to, PBMC-EBV load, unlike 2/7 HIV-positive brain lymphoma patients. CONCLUSIONS: During HIV infection PBMC-EBV load rises in comparison to healthy carriers, but decreases when immunosuppression progresses and CD4+ T cell count becomes <50/mm(3). Circulating EBV is mainly cell-associated in the HIV-infected population. Neither PBMC-EBV nor plasma-EBV loads would be useful to diagnose brain lymphoma in AIDS patients.     

Clinical presentation, treatment, and outcomes among 65 patients with HIV-associated lymphoma treated at the University of North Carolina, 2000-2010

HIV increases risk of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL). The effect of HIV on presentation, treatment, and outcomes of NHL and HL in routine care in the combination antiretroviral therapy (cART) merits further characterization. We performed a retrospective analysis of HIV-infected patients with NHL and HL receiving care at the University of North Carolina at Chapel Hill from January 1, 2000 until December 31, 2010. Statistical analyses were conducted using SAS, version 9.2 (SAS Institute Inc). Sixty-five HIV-infected patients with NHL and HL were identified. Patients with non-CNS NHL and HL presented with advanced disease (85% stage III or IV) and adverse prognostic features. Patients completed 87% of planned chemotherapy cycles, and 68% of patients completed stage-appropriate therapy. Dose reduction, interruption, and/or delay occurred during more than 25% of administered cycles in 64% of patients. Infectious complications, febrile neutropenia, and myelosuppression accounted for 78% of deviations from planned cumulative dose and dose intensity. Primary CNS lymphoma (PCNSL) was associated with poor prognosis, but 2-year overall survival was 66% for all non-CNS lymphoma. Among patients surviving at least 2 years, 75% had CD4 count >200 cells/μl and 79% had HIV viral load <400 copies/ml at last follow-up. Despite advanced disease and difficulty tolerating chemotherapy with optimal cumulative dose and dose intensity, most patients with non-CNS HIV-associated lymphoma survived more than 2 years after diagnosis, the majority with suppressed HIV RNA.     

Epstein-Barr virus in benign lymph node biopsies from individuals infected with the human immunodeficiency virus is associated with concurrent or subsequent development of non-Hodgkin's lymphoma.

Individuals infected with the human immunodeficiency virus (HIV) have an increased incidence of high-grade B-cell lymphoma. In many instances, these lymphomas contain Epstein-Barr viral (EBV) genomes. To investigate the role of EBV in development of HIV-related lymphoma, benign fixed lymph node biopsies from normal individuals and HIV-infected individuals with persistent generalized lymphadenopathy (PGL) were analyzed for EBV sequences by polymerase chain reaction and in situ DNA hybridization techniques. EBV DNA was not detected in any of 16 benign lymph node biopsies from normal individuals, but could be detected from 13 of 35 PGL biopsies. The EBV-infected cells were present in both follicular and interfollicular areas and in both small and large lymphoid cells. The presence of detectable amounts of EBV DNA in the 13 PGL biopsies was associated with an increased incidence of concurrent lymphoma at another site (n = 3) or development of lymphoma in time (n = 2). In contrast, only 1 of 22 individuals with EBV-negative PGL biopsies developed lymphoma in time (P less than .05). EBV was detected in all five lymphomas in which tissue was available for subsequent analysis, including the lymphoma that developed in the individual without EBV in his previous PGL biopsy. These findings support the hypothesis that EBV plays a role in development of some HIV-related lymphomas. Detectable EBV lymphoproliferations occur in a few PGL biopsies and are associated with a significant risk of EBV DNA-positive non-Hodgkin's lymphoma.     

Viral genomes and antigen detection of hepatitis B and C viruses in involved lymph nodes of Egyptian non-Hodgkin's lymphoma patients

Several studies have suggested an association between Hepatitis C and B viruses (HCV and HBV) and non-Hodgkin's lymphoma (NHL). In the present study we have searched for viral genomes and antigens in the malignant lymphoma tissues as well as their seroprevalence. Antibodies against Hepatitis C as well as HCV RNA and hepatitis B surface antigen (HBsAg) were determined for 29 newly diagnosed non-Hodgkin's lymphoma patients using an enzyme linked immunosorbent assay (ELISA), as well as RT-PCR and compared with 36 apparently healthy individuals as a control group for viral markers. Immunohistochemical staining (IHC) was performed on paraffin embedded tissues for the NS3 of HCV and for HBsAg of HBV using the immunoperoxidase technique. Paraffin embedded lymph nodes (LN) were studied for the presence of viral sequences. Ten non-metastatic lymph nodes (LN) from cancer cases other than NHL were used as a control for IHC and molecular studies. HCV was significantly more encountered in patients with NHL when compared to controls for both antibodies (27.6% versus 8.3% of serum controls; p = 0.04), and antigens studied by IHC in the involved LN (41% versus 10% of tissue controls; p = 0.06). Although HBsAg positivity was not different in NHL patients when compared to controls (6.9% and 2.7%); yet it was significantly more encountered in LN of NHL patients (p = 0.04). HBV-DNA was detected in 27.5% of patient's samples and none of the controls. In conclusion, overall our findings confirm the presence of HBV and HCV antigens and viral sequences in the involved LNs of NHL patients, except for HCV RNA which perhaps necessitates fresh and not paraffin embedded tissues. These results strengthen the assumption that these viruses may be involved in the development of NHL.