Racial/ethnic variation in EBV-positive classical Hodgkin lymphoma in California populations

M. N. Mydin RB, Che Halim H, Musa MY. A Systematic Review on Clinico-Aetiopathological Trends of Nasopharyngeal Cancer in Asia

BACKGROUND

Nasopharyngeal cancer (NPC) is a type of malignancy that is highly prevalent in Asian countries. Therefore, an understanding between NPC epidemiological trend, the clinico-pathological and aetiological profiles are needed. This systematic review focuses on asian countries demographic and clinico-pathological presentation reported in 9982 NPC cases diagnosed from the year 2010 to 2021.

METHODOLOGY

Data were extracted from databases, such as PubMed, Springer Link, Science Direct, Google Scholar and general search engines, by using pre-determined keywords (e.g. clinico-pathological data, age, sex, tumour stage, nasopharyngeal cancer, nasopharyngeal carcinoma, naso-pharynx and cancer in Asia).

RESULTS AND CONCLUSION

Findings from our systematic review shows that from 2010 to 2021, males in age range below 50 years old are at a higher risk of developing NPC in Asia. NPC is mostly diagnosed at advanced stage in Asia, which is likely due to the deep-seated location of the cancer. Type III NPC and EBV proteins (EBNA1 and LMP2A) are frequently associated with reported EBV-positive NPC cases in Asian countries. Meanwhile, NPC type I, II, and III are associated with EBV-negative NPC cases in Asia. Human leucocyte antigen (HLA) alleles (A2, B27, and B46) are frequently present in reported EBV-negative NPC cases in Asia. In Asia, males below 50 years old are more prone to NPC and often diagnosed at late stage. EBV-positive and EBV-negative NPC in Asia have unique histological profiles. Systemic approach of this study may help to provide better knowledge on reported NPC cases especially on the risk factors and clinical presentation focusing in Asian countries.

Association of HLA diversity with the risk of 25 cancers in the UK Biobank

BACKGROUND

The human leukocyte antigen (HLA) is a highly polymorphic region, and HLA diversity may play a role in presenting tumour-associated peptides and inducing immune responses. However, the effect of HLA diversity on cancers has not been fully assessed. We aimed to explore the role of HLA diversity on cancer development.

METHODS

A pan-cancer analysis was performed to evaluate the effect of HLA diversity, measured by HLA heterozygosity and HLA evolutionary divergence (HED), on the susceptibility of 25 cancers in the UK Biobank.

FINDINGS

We observed that the diversity of HLA class II locus was associated with a lower risk of lung cancer (OR_hetero = 0.94, 95% CI = 0.90-0.97, P = 1.29 × 10^-4) and head and neck cancer (OR_hetero = 0.91, 95% CI = 0.86-0.96, P = 1.56 × 10^-3). Besides, a lower risk of non-Hodgkin lymphoma was associated with an increased diversity of HLA class I (OR_hetero = 0.92, 95% CI = 0.87-0.98, P = 8.38 × 10^-3) and class II locus (OR_hetero = 0.89, 95% CI = 0.86-0.92, P = 1.65 × 10^-10). A lower risk of Hodgkin lymphoma was associated with the HLA class I diversity (OR_hetero = 0.85, 95% CI = 0.75-0.96, P = 0.011). The protective effect of HLA diversity was mainly observed in pathological subtypes with higher tumour mutation burden, such as lung squamous cell carcinoma (P = 9.39 × 10^-3) and diffuse large B cell lymphoma (P_{class I} = 4.12 × 10^-4; P_{class Ⅱ} = 4.71 × 10^-5), as well as the smoking subgroups of lung cancer (P = 7.45 × 10^-5) and head and neck cancer (P = 4.55 × 10^-3).

INTERPRETATION

We provided a systematic insight into the effect of HLA diversity on cancers, which might help to understand the etiological role of HLA on cancer development.

FUNDING

This study was supported by grants from the National Natural Science Foundation of China (82273705, 82003520); the Basic and Applied Basic Research Foundation of Guangdong Province, China (2021B1515420007); the Science and Technology Planning Project of Guangzhou, China (201804020094); Sino-Sweden Joint Research Programme (81861138006); the National Natural Science Foundation of China (81973131, 81903395, 81803319, 81802708).

Latent Epstein-Barr virus infection status and prognosis in patients with newly diagnosed Hodgkin lymphoma in Southeast China: a single-center retrospective study

PURPOSE

This study aimed to investigate the latent Epstein-Barr virus (EBV) infection status of patients with newly diagnosed Hodgkin lymphoma (HL) and to discuss the relationship between tumor cell EBV status and the prognosis of HL patients.

PATIENTS AND METHODS

A total of 134 previously untreated HL patients were analyzed in the study. Epstein-Barr virus encoded RNAs (EBERs) in situ hybridization was performed to detect the EBV status of tumor cells.

RESULTS

EBV positive status correlated with sex (p=0.046) and the proportion of extranodal lesions(p=0.037). There was no obvious correlation between EBV status and overall survival (OS) or failure-free survival (FFS) in all cases, but in cases over 50 years old, EBV positive group had an inferior 5-year FFS compared with EBV negative group (38.5%±13.5% vs 90.9%±8.7%, p=0.012). In FFS multivariate analysis of this age subgroup, EBV positive status was associated with significantly inferior survival (HR, 10.10; 95% CI, 1.26-81.08; p=0.030).

CONCLUSION

This study demonstrates positive tumor cell EBV status is an unfavorable prognostic factor in elder HL patients.

Childhood cancer incidence among specific Asian and Pacific Islander populations in the United States

Despite the vast genetic and environmental diversity in Asia, individuals of Asian and Pacific Islander (API) descent are often combined into a single group for epidemiologic analyses within the U.S. We used the Surveillance, Epidemiology and End Results (SEER) Detailed Asian/Pacific Islander Database to calculate incidence rates for discrete groups among children aged 0 to 19 years. Due to sample size constraints we pooled incidence among regional groups based on countries of origin: East Asians (Chinese, Japanese, Korean), Southeast (SE) Asians (Vietnamese, Laotian, Cambodian), Asian Indian/Pakistani, Oceanians (Guamanian, Samoan, Tongan) and Filipinos. Incidence rate ratios (IRR) and 95% confidence intervals (CI) were calculated comparing each API regional group to Non-Hispanic Whites (NHW) and East Asians. Finally, we calculated the correlation between incidence of cancer in specific API ethnicities in SEER and in originating countries in the Cancer Incidence in Five Continents. Incidence rates among API regional groups varied. Acute lymphoblastic leukemia (ALL) was lower in children of SE Asian descent (IRR 0.65, 95% CI 0.44, 0.96) compared to NHW. Acute myeloid leukemia (AML) was more common among children from Oceania compared to NHW (IRR 3.88, 95% CI 1.83, 8.22). East Asians had higher incidence rates than SE Asians but lower rates compared to children from Oceania. Correlation of some incidence rates between US-based API ethnicities and originating countries were similar. The variation observed in childhood cancer incidence patterns among API groups may indicate differences in underlying genetics and/or patterns of exposure.

Molecular Pathogenesis of Hodgkin Lymphoma: Past, Present, Future

Our understanding of the tumorigenesis of classical Hodgkin lymphoma (cHL) and the formation of Reed–Sternberg cells (RS-cells) has evolved drastically in the last decades. More recently, a better characterization of the signaling pathways and the cellular interactions at play have paved the way for new targeted therapy in the hopes of improving outcomes. However, important gaps in knowledge remain that may hold the key for significant changes of paradigm in this lymphoma. Here, we discuss the past, present, and future of cHL, and review in detail the more recent discoveries pertaining to genetic instability, anti-apoptotic signaling pathways, the tumoral microenvironment, and host-immune system evasion in cHL.

Global and regional incidence, mortality and disability-adjusted life-years for Epstein-Barr virus-attributable malignancies, 1990-2017

OBJECTIVE

To determine the global and regional burden of Epstein-Barr virus (EBV)-attributed malignancies.

DESIGN

An international comparative study based on the Global Burden of Disease (GBD) Study estimates.

SETTING

Global population by age, sex, region, demographic index and time.

METHODS AND OUTCOME MEASURES

The burden of EBV-attributed Burkitt lymphoma (BL), Hodgkin lymphoma (HL), nasopharyngeal carcinoma (NPC) and gastric carcinoma (GC) was estimated in a two-step process. In the first step, the fraction of each malignancy attributable to EBV was estimated based on published studies; this was then applied to the GBD estimates to determine the global and regional incidence, mortality and disability-adjusted life-years (DALYs) for each malignancy by age, sex, geographical region and social demographic index (SDI) from 1990 to 2017.

RESULTS

The combined global incidence of BL, HL, NPC and GC in 2017 was 1.442 million cases, with over 973 000 deaths. An estimated 265 000 (18%) incident cases and 164 000 (17%) deaths were due to the EBV-attributed fraction. This is an increase of 36% in incidence and 19% in mortality from 1990. In 2017, EBV-attributed malignancies caused 4.604 million DALYs, of which 82% was due to NPC and GC alone. The incidence of both of these malignancies was higher in high and middle-high SDI regions and peaked in adults aged between 50 and 70 years. All four malignancies were more common in males and the highest burden was observed in East Asia.

CONCLUSIONS

This study provides comprehensive estimates of the burden of EBV-attributed BL, HL, NPC and GC. The overall burden of EBV-related malignancies is likely to be higher since EBV is aetiologically linked to several other malignancies not included in this analysis. Increasing global population and life expectancy is expected to further raise this burden in the future. The urgency for developing an effective vaccine to prevent these malignancies cannot be overstated.

Assessment of tumor Epstein-Barr Virus status and its impact on outcomes in intermediate and high-risk childhood classic Hodgkin Lymphoma treated at a tertiary cancer center in India

Indian studies on EBV in childhood classic Hodgkin Lymphoma (cHL) have mainly analyzed the epidemiology of EBV-positive [EBV(+)HL] or negative HL [EBV(-)HL], with limited data on outcomes. We studied a large cohort of children with intermediate and high-Risk cHL for tumor EBV status and its impact on outcomes retrospectively. Of evaluable 189 patients, 84.7% had EBV(+)HL. Positive status was significantly associated with age ≤ 10 years (p < .001), males (p = .015), non-Nodular Sclerosis (NS) histology (p = .004) and inversely with bulky-mediastinal disease (p < .001). At a median follow-up of 29-months (range1-75), 3-year Event-Free Survival (EFS) for EBV(+)HL and EBV(-)HL was 93.6%(95%CI:89.8%-97.5%), 81.1%(95%CI:67.2%-97.9%), (p = .048) and Overall Survival (OS) was 94.9%(95%CI:91.6%-98.4%), 84.6%(95%CI:71.5%-100%), (p = .075) respectively. Three-year EFS was better in males (HR-0.267,95%CI:0.078-0.916, p = .036) in EBV(+)HL and in patients with serum-albumin > 3g/dL (HR-0.117,95%CI:0.019-0.705, p = .019) in EBV(-)HL. EBV is associated with most of intermediate and high-risk childhood cHL, occurs in younger male patients with non-NS histology, with reduced incidence of bulky-mediastinal disease and favorable survival in childhood cHL.

Hodgkin lymphoma

Hodgkin lymphoma (HL) is a B cell lymphoma characterized by few malignant cells and numerous immune effector cells in the tumour microenvironment. The incidence of HL is highest in adolescents and young adults, although HL can affect elderly individuals. Diagnosis is based on histological and immunohistochemical analyses of tissue from a lymph node biopsy; the tissue morphology and antigen expression profile enable classification into one of the four types of classic HL (nodular sclerosis, mixed cellularity, lymphocyte-depleted or lymphocyte-rich HL), which account for the majority of cases, or nodular lymphocyte-predominant HL. Although uncommon, HL remains a crucial test case for progress in cancer treatment. HL was among the first systemic neoplasms shown to be curable with radiation therapy and multiagent chemotherapy. The goal of multimodality therapy is to minimize lifelong residual treatment-associated toxicity while maintaining high levels of effectiveness. Recurrent or refractory disease can be effectively treated or cured with high-dose chemotherapy followed by autologous haematopoietic stem cell transplantation, and prospective trials have demonstrated the potency of immunotherapeutic approaches with antibody-drug conjugates and immune checkpoint inhibitors. This Primer explores the wealth of information that has been assembled to understand HL; these updated observations verify that HL investigation and treatment remain at the leading edge of oncological research.

Epidemiology and Etiology of Leukemia and Lymphoma

Available evidence suggests that the incidence of leukemia and lymphoma tends to be higher in highly developed regions of the world and among Whites in the United States. Temporal trends in incidence are dynamic and multifactorial; for instance, the incidence of non-Hodgkin's lymphoma increased around the turn of the century, in part because of the acquired immune deficiency syndrome (AIDS) epidemic. Most leukemias and lymphomas are sporadic and the specific etiology remains elusive. Still, research shows that these malignancies often develop in the context of genetic abnormalities, immunosuppression, and exposure to risk factors like ionizing radiation, carcinogenic chemicals, and oncogenic viruses. The prognosis varies by subtype, with poorer survival outcomes for acute leukemias among adults, and more favorable outcomes for Hodgkin's lymphoma. At a time when specific prevention efforts targeting these malignancies are nonexistent, there is a great need to ensure equitable access to diagnostic services and treatments worldwide.

Survival by Race and Ethnicity in Pediatric and Adolescent Patients With Hodgkin Lymphoma: A Children's Oncology Group Study

PURPOSE

Population-based studies of children and adolescents with Hodgkin lymphoma (HL) report a survival disadvantage in nonwhite-non-Hispanic black (NHB) and Hispanic-patients. Whether disparities persist after adjustment for clinical and treatment-related variables is unknown. We examined survival by race/ethnicity in children receiving risk-based, response-adapted, combined-modality therapy for HL in contemporary Children's Oncology Group trials.

PATIENTS AND METHODS

This pooled analysis used individual-level data from 1,605 patients (younger than age 1 to 21 years) enrolled in phase III trials for low-risk (AHOD0431), intermediate-risk (AHOD0031), and high-risk (AHOD0831) HL from 2002 to 2012. Event-free survival (EFS) and overall survival (OS) were compared between non-Hispanic white (NHW) and nonwhite patients. Cox proportional hazards for survival were estimated for both de novo and relapsed HL, adjusting for demographics, disease characteristics, and therapy.

RESULTS

At median follow up of 6.9 years, cumulative incidence of relapse was 17%. Unadjusted 5-year EFS and OS were 83% (SE, 1.2%) and 97% (SE, < 1%), respectively. Neither differed by race/ethnicity. In multivariable analyses for OS, nonwhite patients had a 1.88× higher hazard of death (95% CI, 1.1 to 3.3). Five-year postrelapse survival probabilities by race were as follows: NHW, 90%; NHB, 66%; and Hispanic, 80% (P < .01). Compared with NHW, Hispanic and NHB children had 2.7-fold (95% CI, 1.2 to 6.2) and 3.5-fold (95% CI, 1.5 to 8.2) higher hazard of postrelapse mortality, respectively.

CONCLUSION

In patients who were treated for de novo HL in contemporary Children's Oncology Group trials, EFS did not differ by race/ethnicity; however, adjusted OS was significantly worse in nonwhite patients, a finding driven by increased postrelapse mortality in this population. Additional studies examining treatment and survival disparities after relapse are warranted.

The role of HLA variation in lymphoma aetiology and survival

Epidemiologic and laboratory evidence has consistently supported a strong inflammatory and immune component for lymphoma aetiology. These studies have consistently implicated variation in the immune gene, human leucocyte antigen (HLA), to be associated with lymphoma risk. In this review, we summarize the historical and recent evidence of HLA in both lymphoma aetiology and survival. The recent momentum in uncovering HLA associations has been propelled by the conduct of genome-wide association studies (GWAS), which has permitted the evaluation of imputed HLA alleles in much larger sample sizes than historically feasible with allelotyping studies. Based on the culmination of smaller HLA typing studies and larger GWAS, we now recognize several HLA associations with Hodgkin (HL) and non-Hodgkin lymphomas (NHLs) and their subtypes. Although other genetic variants have also been implicated with lymphoma risk, it is notable that HLA associations have been reported in every NHL and HL subtype evaluated to date. Both HLA class I and class II alleles have been linked with NHL and HL risk. It is notable that the associations identified are largely specific to each lymphoma subtype. However, pleiotropic HLA associations have also been observed. For example, rs10484561, which is in linkage disequilibrium with HLA-DRB1*01:01˜DQA1*01:01˜DQB1*05:01, has been implicated in increased FL and DLBCL risk. Opposing HLA associations across subtypes have also been reported, such as for HLA-A*01:01 which is associated with increased risk of EBV-positive cHL but decreased risk of EBV-negative cHL and chronic lymphocytic leukaemia/small cell lymphoma. Due to extensive linkage disequilibrium and allele/haplotypic variation across race/ethnicities, identification of causal alleles/haplotypes remains challenging. Follow-up functional studies are needed to identify the specific immunological pathways responsible in the multifactorial aetiology of HL and NHL. Correlative studies linking HLA alleles with known molecular subtypes and HLA expression in the tumours are also needed. Finally, additional association studies investigating HLA diversity and lymphoma survival are also required to replicate initial associations reported to date.

Whitehurst C, Qadri I, Shackelford J, Pagano JS, Muhammad D, Richards KL. Prevalence of Epstein–Barr Virus Genotypes in Pakistani Lymphoma Patients

The Epstein-Barr virus (EBV) is a herpesvirus infecting more than 90% of the human population. The tropism of EBV for B lymphocytes is evidenced in its association with many lymphoproliferative disorders. Different types of EBV (EBV-1 and EBV-2), classified on the basis of EBV nuclear antigen-2 (EBNA-2) genotyping, have been reported in benign and malignant pathologies, but there is almost no information about their frequency in the Pakistani population. The aim of this study was to determine the frequency and distribution of EBNA-2-based EBV genotypes in lymphoma patients. Genomic DNA was extracted from formalin-fixed paraffin embedded (FFPE) tissue samples obtained from 73 EBV-DNA-positive lymphoma patients. The β-globin gene was amplified to assess the presence and quality of cellular DNA from all samples. EBER-1 DNA was detected by PCR to confirm EBV presence in tissue samples. EBNA-1 mRNA relative quantification done by quantitative PCR substantiated EBNA-1 mRNA overexpression in 43.8% of EBV-positive cases in comparison to EBV-positive control cell line. EBNA-2 genotyping was done by nested PCR. Among typable samples, EBV-1 was found in 90.7% of samples while EBV-2 was present in 9.3% cases. These results show that EBV-1 was the most prevalent type in the lymphoma population of Pakistan. This epidemiology of EBV in Pakistani lymphoma patients represents an important first step in using EBV for prognosis and monitoring treatment response.

Expression pattern of PD-L1 and PD-L2 in classical Hodgkin lymphoma, primary mediastinal large B-cell lymphoma, and gray zone lymphoma

OBJECTIVES

We aimed at investigating the relationship between classical Hodgkin lymphoma (cHL), primary mediastinal large B-cell lymphoma (PMBL), and gray zone lymphoma (GZL) with intermediate characteristics between cHL and PMBL, from the perspective of the aberration in programed cell death 1 and the programed death ligands (PDLs) network.

METHODS

We explored the expression levels of PDLs and chromosomal anomalies in 67 cases: 34 cases with cHL, 20 with PMBL, and 13 with GZL, using immunohistochemical analyses and Fluorescence In Situ Hybridization (FISH).

RESULTS

Twenty-one cHL (62%), 3 PMBL (15%), and 6 GZL (46%) cases showed staining to PD-L1 antibodies in more than 70% of tumor cells. Two cHL (6%), 10 PMBL (50%), and 3 GZL (23%) cases were not stained by PD-L1 antibodies. Patients over 40 years old manifest more frequent expression of PD-L1 in cHL. Proportion of tumors stained by PD-L2 antibody was increased in PMBL. FISH analyses with a PD-L1/PD-L2 probe detected 5 amplification, 1 gain, and 7 polysomy cases in cHL, 1 amplification and 1 polysomy case in GZL, and amplification in 1 PMBL case.

CONCLUSION

We identified increased staining of PD-L1 in cHL and that of PD-L2 in PMBL. GZL had a pattern similar to that of cHL.

Health Disparities and the Global Landscape of Lymphoma Care Today

Lymphoma encompass a wide variety of distinct disease entities, including, but not limited to, subtypes of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL). In the last 3 decades, therapeutic advancements have resulted in substantial improvements in lymphoma outcome. In most high-income regions, HL is a largely curable disease and for patients with two frequent subtypes of NHL, diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL), survival has dramatically improved with the incorporation of rituximab as a standard treatment approach. Despite these advances, outcomes vary between and across populations. This review will provide updated information about health disparities in lymphoma in the United States and across the globe.

Monoamine oxidase A is highly expressed in classical Hodgkin lymphoma

Monoamine oxidase A (MAOA) is a mitochondrial enzyme that catalyzes oxidative deamination of neurotransmitters and dietary amines and produces H₂ O₂ . It facilitates the progression of gliomas and prostate cancer, but its expression and functional relevance have not been studied in lymphoma. Here, we evaluated MAOA in 427 cases of Hodgkin and non-Hodgkin lymphoma and in a spectrum of reactive lymphoid tissues by immunohistochemistry on formalin-fixed, paraffin-embedded specimens. MAOA was expressed by Hodgkin Reed-Sternberg (HRS) cells in the majority of classical Hodgkin lymphomas (cHLs) (181/241; 75%), with 34.8% showing strong expression. Weak MAOA was also noted in a minority of primary mediastinal large B-cell lymphomas (8/47; 17%) and in a mediastinal gray-zone lymphoma. In contrast, no MAOA was found in non-neoplastic lymphoid tissues, nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL; 0/8) or any other non-Hodgkin lymphomas studied (0/123). MAOA was more common in Epstein-Barr virus (EBV)-negative compared to EBV-positive cHL (p < 0.0001) and was especially prevalent in the EBV-negative nodular sclerosing subtype. Similar to primary human lymphoma specimens, most cHL-derived cell lines displayed MAOA activity, whereas non-Hodgkin-lymphoma-derived cell lines did not. The MAOA inhibitor clorgyline reduced the growth of L1236 cells and U-HO1 cells, and shRNA knockdown of MAOA reduced the growth of L1236 cells. Conversely, ectopic overexpression of MAOA increased the growth of MAOA-negative HDLM2 cells. Combined treatment with clorgyline and ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) was more effective in reducing cell growth than either regimen alone. In summary, MAOA is highly expressed in cHL and may reflect the distinct biology of this lymphoma. Further studies on the potential utility of MAOA as a diagnostic marker and therapeutic target are warranted. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

HLA expression and HLA type associations in relation to EBV status in Hispanic Hodgkin lymphoma patients

A proportion of classical Hodgkin lymphomas harbor the Epstein Barr virus (EBV). We previously demonstrated that associations between Human Leukocyte Antigen (HLA) alleles and susceptibility to EBV+ classical Hodgkin lymphoma differ between European and Chinese populations. Data on Hispanic populations is missing. Here we examined the association between HLA type, tumor cell HLA expression and other characteristics in Hispanic Hodgkin lymphoma patients. Hispanic Hodgkin lymphoma patients diagnosed at the Los Angeles County-University of Southern California Medical Center from 2000–2012 were included (n = 65). Formalin-fixed paraffin-embedded tumor tissue was analyzed for EBV by in situ hybridization and for HLA class I and class II expression by immunohistochemistry. HLA typing was performed by HLA-A specific quantitative PCR of genomic DNA from tissue. Thirty patients (46%) had EBV+ tumors. Expression of HLA class I (p = 0.0006) was significantly associated with EBV+ tumor status in Hispanic patients, similar to Europeans and Chinese. A positive association between HLA class II expression and EBV+ tumor status, as present in large studies in Europeans, was not found (p = 0.06). The prevalences of the specific European HLA-A*01 risk and European HLA-A*02 protective types were not significantly associated with EBV+ tumors among these Hispanic patients, however numbers were too low to draw firm conclusions. The HLA-A*02:07 allele, that is associated with EBV+ Hodgkin lymphoma in Chinese, was absent. In conclusion, the association between EBV positivity in tumor cells and HLA class I expression appears to be consistent across different populations. Larger studies in Hispanics are needed to evaluate HLA allele susceptibility associations.

Variation in risk and outcomes of Epstein-Barr virus-associated breast cancer by epidemiologic characteristics and virus detection strategies: an exploratory study

PURPOSE

A relationship of Epstein-Barr virus (EBV) and breast cancer etiology and outcome may have clinical utility and potential to enhance understanding of tumor biology. Research to date has yielded variable results, likely reflecting differing virus detection assays and unaddressed epidemiologic heterogeneity across studies.

METHODS

Applying our novel, five-target assay detection strategy in an exploratory study, we examined demographic, clinical, and tumor characteristics, and overall survival, associated with EBV positivity in breast adenocarcinomas from 59 non-Hispanic white and 68 Hispanic women sampled by age (<50, 50+) and stage (localized, regional/remote) and examined associations based on single assay targets.

RESULTS

EBV was localized only to lymphocytes. Nevertheless, viral prevalence, although low, varied across patient subgroups. Adjusted odds ratios (OR) for EBV positivity were lower for younger Hispanic than white women (p _interaction = 0.05), and marginally higher for larger [OR (95% confidence intervals) 1.03 (1.00-1.05) per mm increase] and right-sided [2.8 (0.97-7.8)] tumors. In whites, ORs were marginally higher for larger tumors [1.04 (1.00-1.07)] and marginally lower for age 50+ [0.24 (0.06-1.03)]; in Hispanics, ORs were higher for ER negative [5.6 (1.1-30.5)], and marginally higher for right-sided, tumors [5.8 (0.94-36.2)]. Survival was suggestively poorer for EBV-positive than EBV-negative tumors in older women with localized disease. EBV associations differed across single assay targets, indicating variation in prior findings likely due to assay performance.

CONCLUSIONS

The differing EBV associations by age and race/ethnicity suggest a non-random role of EBV in breast cancer and support further study using multi-target assays, relevant epidemiologic design, and a larger study sample.

Association of DDX58 177 C > T polymorphism with decreased risk of Epstein-Barr virus-related nodular sclerosis classical Hodgkin lymphoma

Classical Hodgkin lymphoma (cHL) is frequently related to Epstein-Barr virus (EBV) infection. Its malignant capacity is attributed to disruption of an EBV-host balance influenced by environmental and genetic drivers. EBV structures activate Type I interferon (IFN) pathway of the innate immunity, therefore, genetic polymorphisms could influence this response. We explored the impact of four single nucleotide polymorphisms (SNPs) on EBV-associated cHL susceptibility. Toll-like receptors 9 (TLR9_rs5743836), and 3 (TLR3_rs3775291), Interleukin-28B (IL28B_rs12979860), and DEAD-box polypeptide 58 (DDX58_rs10813831) were genotyped in 73 EBV-positive and 106 EBV-negative cHL patients and 396 controls. Only DDX58_rs10813831 T-allele was decreased among EBV-positive cHL compared to controls. A stratified analysis in EBV-positive cHL showed that the reduced rate was associated with younger age and nodular sclerosis. In conclusion, DDX58_rs10813831 T-allele may be associated with a reduced risk of nodular sclerosis EBV-related cHL, which suggests a role for RIG-I (retinoic acid-inducible gene I), encoded by DDX58, in these cases.

Cancers in Australia in 2010 attributable to modifiable factors: introduction and overview

OBJECTIVE

To describe the approach underpinning a national project to estimate the numbers and proportions of cancers occurring in Australia in 2010 that are attributable to modifiable causal factors.

METHODS

We estimated the population attributable fraction (PAF) (or prevented fraction) of cancers associated with exposure to causal (or preventive) factors using standard formulae. Where possible, we also estimated the potential impact on cancer incidence resulting from changes in prevalence of exposure. Analyses were restricted to factors declared causal by international agencies: tobacco smoke; alcohol; solar radiation; infectious agents; obesity; insufficient physical activity; insufficient intakes of fruits, vegetables and fibre; red and processed meat; menopausal hormone therapy (MHT); oral contraceptive pill (OCP); and insufficient breast feeding. Separately, we estimated numbers of cancers prevented by: aspirin; sunscreen; MHT; and OCP use. We discuss assumptions pertaining to latent periods between exposure and cancer onset, choices of prevalence data and risk estimates, and approaches to sensitivity analyses.

RESULTS

Numbers and population attributable fractions of cancer are presented in accompanying papers.

CONCLUSIONS

This is the first systematic assessment of population attributable fractions of cancer in Australia.

Cancers in Australia in 2010 attributable to infectious agents

OBJECTIVES

To estimate the proportion and numbers of cancers in Australia in 2010 attributable to infectious agents.

METHODS

The population attributable fraction (PAF) and number of cancers caused by hepatitis B and C viruses (HBV, HCV), Helicobacter pylori and human immunodeficiency virus (HIV) were calculated using standard formulae incorporating prevalence of infection in the Australian population, the relative risks associated with that infection and cancer incidence. For cancers with very strong associations to the infectious agent (Epstein-Barr virus [EBV], human papillomavirus [HPV] and HIV/Kaposi's sarcoma herpes virus [KSHV]), calculations were based on viral prevalence in the tumour.

RESULTS

An estimated 3,421 cancers (2.9% of all cancers) in Australia in 2010 were attributable to infections. Infectious agents causing the largest numbers of cancers were HPV (n=1,706), H. pylori (n=793) and HBV/HCV (n=518). Cancer sites with the greatest number of cancers caused by infections were cervix (n=818), stomach (n=694) and liver (n=483). Cancers with highest proportions attributable to infectious agents were Kaposi's sarcoma (100%), cervix (100%), nasopharynx (87%), anus (84%) and vagina (70%).

CONCLUSIONS

Infectious agents cause more than 3,000 cancers annually in Australia.

IMPLICATIONS

Opportunities for cancer prevention through infection control are considerable, even in a 'first world' nation like Australia.

Racial, Ethnic, and Age Differences in the Incidence and Survival of Childhood Cancer in Oklahoma, 1997-2012

While cancer is relatively rare in children under 20, it is the leading cause of disease-related death among children aged 5 to 14 years. We aimed to describe the incidence and survival of childhood cancer in Oklahoma from 1997-2012. We calculated age-adjusted incidence rates and five-year observed survival by cancer type using Oklahoma Central Cancer Registry and Surveillance, Epidemiology, and End Results program data among children diagnosed with cancer under the age of 20 from 1997-2012. The average annual age-adjusted incidence rate of childhood cancer was 168.9 per million for the US and 171.7 per million for Oklahoma. Overall, Oklahoma had lower survival from childhood cancer compared to the US (77.0% v. 80.6%). In recent years, research has been conducted on the epidemiology of childhood cancer. Little research has been done, however, on the incidence or survival of childhood cancer at state levels and none focused exclusively on Oklahoma.

Familial predisposition and genetic risk factors for lymphoma

Our understanding of familial predisposition to lymphoma (collectively defined as non-Hodgkin lymphoma [NHL], Hodgkin lymphoma [HL], and chronic lymphocytic leukemia [CLL]) outside of rare hereditary syndromes has progressed rapidly during the last decade. First-degree relatives of NHL, HL, and CLL patients have an ∼1.7-fold, 3.1-fold, and 8.5-fold elevated risk of developing NHL, HL, and CLL, respectively. These familial risks are elevated for multiple lymphoma subtypes and do not appear to be confounded by nongenetic risk factors, suggesting at least some shared genetic etiology across the lymphoma subtypes. However, a family history of a specific subtype is most strongly associated with risk for that subtype, supporting subtype-specific genetic factors. Although candidate gene studies have had limited success in identifying susceptibility loci, genome-wide association studies (GWAS) have successfully identified 67 single nucleotide polymorphisms from 41 loci, predominately associated with specific subtypes. In general, these GWAS-discovered loci are common (minor allele frequency >5%), have small effect sizes (odds ratios, 0.60-2.0), and are of largely unknown function. The relatively low incidence of lymphoma, modest familial risk, and the lack of a screening test and associated intervention, all argue against active clinical surveillance for lymphoma in affected families at this time.

HLA Allele E*01:01 Is Associated with a Reduced Risk of EBV-Related Classical Hodgkin Lymphoma Independently of HLA-A*01/*02

BACKGROUND

An inefficient immune response against Epstein-Barr virus (EBV) infection is related to the pathogenesis of a subgroup of classical Hodgkin lymphomas (cHL). Some EBV immune-evasion mechanisms target HLA presentation, including the non-classical HLA-E molecule. HLA-E can be recognized by T cells via the TCR, and it also regulates natural killer (NK) cell signaling through the inhibitory CD94/NKG2A receptor. Some evidences indicate that EBV-infected B-cells promote the proliferation of NK subsets bearing CD94/NKG2A, suggesting a relevant function of these cells in EBV control. Variations in CD94/NKG2A-HLA-E interactions could affect NK cell-mediated immunity and, consequently, play a role in EBV-driven transformation and lymphomagenesis. The two most common HLA-E alleles, E*01:01 and E*01:03, differ by a single amino acid change that modifies the molecule function. We hypothesized that the functional differences in these variants might participate in the pathogenicity of EBV.

AIM

We studied two series of cHL patients, both with EBV-positive and-negative cases, and a cohort of unrelated controls, to assess the impact of HLA-E variants on EBV-related cHL susceptibility.

RESULTS

We found that the genotypes with at least one copy of E*01:01 (i.e., E*01:01 homozygous and heterozygous) were underrepresented among cHL patients from both series compared to controls (72.6% and 71.6% vs 83%, p = 0.001). After stratification by EBV status, we found low rates of E*01:01-carriers mainly among EBV-positive cases (67.6%). These reduced frequencies are seen independently of other factors such as age, gender, HLA-A*01 and HLA-A*02, HLA alleles positively and negatively associated with the disease (adjusted OR = 0.4, p = 0.001). Furthermore, alleles from both HLA loci exert a cumulative effect on EBV-associated cHL susceptibility.

CONCLUSIONS

These results indicate that E*01:01 is a novel protective genetic factor in EBV-associated cHL and support a role for HLA-E recognition on the control of EBV infection and lymphomagenesis.

Hodgkin lymphoma incidence in ethnic enclaves in California

Hodgkin lymphoma (HL) incidence varies with migration and nativity, suggesting an influence of acculturation on risk. In population-based California data including 1483 Hispanic and 348 Asian/Pacific Islander (API) HL cases, we examined HL rates in residential neighborhoods classified by ethnic enclave status (measuring degree of acculturation) and socioeconomic status (SES). Rates were inversely associated with enclave intensity, although associations varied by gender and race. In females, the enclave effect was stronger in low-SES settings, but rates were higher in less-ethnic/high-SES than more-ethnic/low-SES neighborhoods--diminishing enclave intensity affected rates more than higher SES. In Hispanics, associations were modest, and only females experienced SES modification of rates; in APIs, the enclave effect was much stronger. Thus, acculturation measured by residence in ethnic enclaves affects HL rates independently of neighborhood SES but in complex patterns. Living in less-ethnic neighborhoods may increase HL rates by facilitating social isolation and other gender-specific exposures implicated in risk.

LMP1 mediates multinuclearity through downregulation of shelterin proteins and formation of telomeric aggregates

Hodgkin lymphoma (HL) and Burkitt lymphoma are both germinal center-derived B-cell lymphomas. To assess the consequences of permanent latent membrane protein 1 (LMP1) expression as observed in tumor cells of Epstein-Barr virus (EBV) -associated HL, we analyzed 3-dimensional (3D) telomere dynamics and measured the expression of shelterin proteins at the transcriptional and translational level and their topographic distribution in the EBV-negative Burkitt cell line BJAB stably transfected with an inducible LMP1 system. Stable LMP1 expression led to a highly significant increase of multinucleated cells, nuclear volume, and 3D telomeric aggregates when compared with the LMP1-suppressed BJAB controls. Most importantly, LMP1 induced a significant downregulation of the shelterin components TRF1, TRF2, and POT1 at the transcriptional and translational level, and this downregulation was reversed after resuppression of LMP1. In addition, as revealed by spectral karyotyping, LMP1 induced "outré" giant cells and hypoploid "ghost" cells. This LMP1-induced multinucleation was blocked upon LMP1-independent TRF2 expression. These results show that LMP1-dependent deregulation of telomere stability and nuclear organization via shelterin downregulation, in particular TRF2, favors chromosomal rearrangements. We speculate that telomeric aggregates and ongoing breakage-bridge-fusion cycles lead to disturbed cytokinesis and finally to multinuclearity, as observed in EBV-associated HL.

Global burden of deaths from Epstein-Barr virus attributable malignancies 1990-2010

Background

Epstein-Barr virus (EBV) is an oncogenic virus implicated in the pathogenesis of a number of human malignancies of both lymphoid and epithelial origin. Thus, a comprehensive and up-to-date analysis focused on the global burden of EBV-attributable malignancies is of significant interest.

Methods

Based on published studies, we estimated the proportion of Burkitt’s lymphoma (BL), Hodgkin’s lymphoma (HL), nasopharyngeal carcinoma NPC), gastric carcinoma (GC) and post-transplant lymphoproliferative disease (PTLD) attributable to EBV, taking into consideration age, sex and geographical variations. This proportion was then imputed into the Global Burden of Disease 2010 dataset to determine the global burden of each EBV-attributable malignancy in males and females in 20 different age groups and 21 world regions from 1990 to 2010.

Results

The analysis showed that the combined global burden of deaths in 2010 from all EBV-attributable malignancies was 142,979, representing 1.8% of all cancer deaths. This burden has increased by 14.6% over a period of 20 years. All 5 EBV-attributable malignancies were more common in males in all geographical regions (ratio of 2.6:1). Gastric cancer and NPC accounted for 92% of all EBV-attributable cancer deaths. Almost 50% of EBV-attributed malignancies occurred in East Asia. This region also had the highest age-standardized death rates for both NPC and GC.

Conclusions

Approximately 143,000 deaths in 2010 were attributed to EBV-associated malignancies. This figure is likely to be an underestimate since some of the less prevalent EBV-associated malignancies have not been included. Moreover, the global increase in population and life-expectancy will further increase the overall burden of EBV-associated cancer deaths. Development of a suitable vaccine could have a substantial impact on reducing this burden.

Electronic supplementary material

The online version of this article (doi:10.1186/1750-9378-9-38) contains supplementary material, which is available to authorized users.

A meta-analysis of Hodgkin lymphoma reveals 19p13.3 TCF3 as a novel susceptibility locus

Recent genome-wide association studies (GWAS) of Hodgkin lymphoma (HL) have identified associations with genetic variation at both HLA and non-HLA loci; however, much of heritable HL susceptibility remains unexplained. Here we perform a meta-analysis of three HL GWAS totaling 1,816 cases and 7,877 controls followed by replication in an independent set of 1,281 cases and 3,218 controls to find novel risk loci. We identify a novel variant at 19p13.3 associated with HL (rs1860661; odds ratio (OR)=0.81, 95% confidence interval (95% CI) = 0.76-0.86, P(combined) = 3.5 × 10(-10)), located in intron 2 of TCF3 (also known as E2A), a regulator of B- and T-cell lineage commitment known to be involved in HL pathogenesis. This meta-analysis also notes associations between previously published loci at 2p16, 5q31, 6p31, 8q24 and 10p14 and HL subtypes. We conclude that our data suggest a link between the 19p13.3 locus, including TCF3, and HL risk.

Hodgkin lymphoma incidence in California Hispanics: influence of nativity and tumor Epstein-Barr virus

PURPOSE

For classical Hodgkin lymphoma (HL), migrant studies could elucidate contributions of environmental factors (including Epstein-Barr virus (EBV)) to the lower rates in non-whites. Given the well-described etiologic complexity of HL, this research requires a large, immigrant population, such as California Hispanics.

METHODS

With 1988-2004 California Cancer Registry data (2,595 Hispanic, 8,637 white HL cases) and tumor cell EBV status on a subset (218 Hispanics, 656 whites), we calculated ethnicity- and nativity-specific HL incidence rates simultaneously by age, sex, and histologic subtype, and tumor cell EBV prevalence.

RESULTS

Compared with white rates, Hispanic HL rates were lower overall (70 %) and for nodular sclerosis HL, particularly among young adults (60-65 % for females). However, they were higher among children (200 %) and older adults, and for mixed cellularity HL. Compared with rates in foreign-born Hispanics, rates in US-born Hispanics were higher among young adults (>threefold in females), lower for children and adults over age 70, and consistently intermediate compared with rates in whites. EBV tumor prevalence was 67, 32, and 23 % among foreign-born Hispanics, US-born Hispanics, and whites, respectively, although with variation by age, sex, and histology.

CONCLUSIONS

Findings strongly implicate environmental influences, such as nativity-related sociodemographic differences, on HL occurrence. In addition, lower young adult rates and higher EBV prevalence in US-born Hispanics than in whites raise questions about the duration/extent of environmental change for affecting HL rates and also point to ethnic differences in genetic susceptibility. Lesser variation in mixed cellularity HL rates and greater variation in rates for females across groups suggest less modifiable factors interacting with environmental influences.

Comparison of Latino and non-Latino patients with Ewing sarcoma

BACKGROUND

Ewing sarcoma (ES) is a malignancy of bone and soft tissue in children and adults. Previous registry-based studies indicate that Latino patients with ES have inferior outcomes compared to non-Latino patients, though an etiology for this difference could not be identified. To explore possible differences that might underlie this disparity, we conducted a retrospective study to compare clinical characteristics, tumor features, healthcare access, and treatment outcomes between Latino and non-Latino patients with ES.

METHODS

Primary data for 218 ES patients treated at two academic medical centers between 1980 and 2010 were collected. Categorical data were compared using Fisher exact tests; Wilcoxon rank-sum tests were used for continuous variables. Survival was estimated using Kaplan-Meier analysis and compared using log-rank testing.

RESULTS

Latino patients were diagnosed at a younger age (P = 0.014). All other clinical and histological data were similar between groups, including radiologic and histologic response to neoadjuvant chemotherapy. Latino patients had lower socioeconomic status (P = 0.001), were less likely to have insurance (P = 0.001), and were more likely to present to the emergency room at onset of symptoms (P = 0.031) rather than to primary care physicians. Five-year event free survival (EFS) and overall survival (OS) were similar between Latino and non-Latino patients (EFS: 60.5% vs. 50.9% P = 0.37; OS: 77.6% vs. 68.6% P = 0.54).

CONCLUSION

Latino patients with ES present at a younger age, and have evidence of impaired access to healthcare. Response to initial therapy appears similar between Latino and non-Latino patients.

Epstein-Barr virus and Hodgkin lymphoma in Jordan

BACKGROUND AND OBJECTIVES

This study aims to examine the possible association of Epstein-Barr virus (EBV) in Classical Hodgkin lymphoma (cHL) and to shed light on the epidemiology of Hodgkin lymphoma (HL) in Jordan.

PATIENTS AND METHODS

We examined 100 consecutive cases of HL for the presence of EBV in tumor cells by immunohistochemistry for latent membrane protein-1 (LMP-1). We collected patient data on age, sex and histologic subtype. We reviewed the pathological findings in each case and confirmed diagnosis.

RESULTS

Nodular lymphocyte predominant HL was diagnosed in 6% of the cases and these were negative for EBV LMP-1. Of the 94 cases of cHL, 65% were males, the most common subtype was nodular sclerosis (NS), representing 70% of the cases, and 45.7% of cHL (43% of all HL) cases were positive for EBV LMP-1. The positive cases were significantly related to age: ⩽15 years and >51 years (p: 0.009 and 0.014 respectively), male gender (p: 0.03) and mixed cellularity (MC) subtype (p: <0.0001). In line with other developing countries, there also appears to be a trend towards a decreasing association of EBV with cHL and a subtype switch from MC to NS in Jordan.

CONCLUSION

The epidemiology of HL in Jordan and some developing countries is approaching that of developed countries.

Birth characteristics and risk of lymphoma in young children

BACKGROUND

Lymphoma is the third most common childhood malignancy and comprises two types, Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). The etiology of pediatric lymphomas is largely unknown, but has been suggested to have prenatal origins.

METHODS

In this population-based study, California birth certificates were identified for 478 lymphoma cases diagnosed in children 0-5 years of age between 1988 and 2007; 208,015 controls frequency-matched by birth year were randomly selected from California birth records.

RESULTS

Compared to non-Hispanic whites, Hispanic children had an increased risk of HL (odds ratio (OR) and 95% confidence interval (CI) 2.43 [1.14, 5.17]), and in particular, were diagnosed more often with the mixed cellularity subtype. For all types of lymphoma, we observed an about twofold risk increase with indicators for high risk pregnancies including tocolysis, fetopelvic disproportion and previous preterm birth. NHL risk doubled with the complication premature rupture of membranes (OR and 95% CI 2.18 [1.12, 4.25]) and HL with meconium staining of amniotic fluids (OR and 95% CI 2.55 [1.01, 6.43]).

CONCLUSION

These data support previously reported associations between Hispanic ethnicity and HL and suggest that pregnancy related factors, such as intra-uterine infections and factors associated with preterm labor, may be involved in lymphoma pathogenesis.

Changing trend of Epstein-Barr virus association in Hodgkin lymphoma in the Republic of Korea

Hodgkin lymphoma (HL) in resource-poor population shows an early childhood peak with predominance of mixed cellularity (MCHL) and high Epstein-Barr virus (EBV) association, whereas HL in resource-rich population has a peak in ages 15-29 years with the predominance of nodular sclerosis (NSHL) and low EBV association. We examined the changing trend of HL in association with EBV in Korea in 385 cases of HL (1980-2011). Data from 1980-1995 and 1996-2011 were compared. Age distribution showed a marked decrease in children (age < 15 years) (21.0 % to 8.6 %, p = 0.004) and sharp increase in young adults (ages 15-29 years) and ages 30-59 years. Male predominance decreased from 3.04 to 1.57. Predominant subtype changed from MCHL to NSHL; MCHL fell from 53.3 % to 26.4 % (p < 0.001), and NSHL rose from 24.8 % to 58.2 % (p < 0.001). EBV-positive HL decreased from 66.7 % to 38.2 %. However, in young adult females, EBV positive cases increased, contributing to the peak in this age group. Epidemiology of HL in Korea is rapidly changing into a Western pattern concurrent with the socioeconomic changes. Analysis of the cases stratified by EBV status and sex identified a smaller hidden peak in the young adult age, which confirms the four disease hypothesis proposed by Jarrett. We propose EBV testing as an essential component in epidemiologic study of Hodgkin lymphoma.

Cigarette smoking and risk of Hodgkin lymphoma and its subtypes: a pooled analysis from the International Lymphoma Epidemiology Consortium (InterLymph)

BACKGROUND

The etiology of Hodgkin lymphoma (HL) remains incompletely characterized. Studies of the association between smoking and HL have yielded ambiguous results, possibly due to differences between HL subtypes.

PATIENTS AND METHODS

Through the InterLymph Consortium, 12 case-control studies regarding cigarette smoking and HL were identified. Pooled analyses on the association between smoking and HL stratified by tumor histology and Epstein-Barr virus (EBV) status were conducted using random effects models adjusted for confounders. Analyses included 3335 HL cases and 14 278 controls.

RESULTS

Overall, 54.5% of cases and 57.4% of controls were ever cigarette smokers. Compared with never smokers, ever smokers had an odds ratio (OR) of HL of 1.10 [95% confidence interval (CI) 1.01-1.21]. This increased risk reflected associations with mixed cellularity cHL (OR = 1.60, 95% CI 1.29-1.99) and EBV-positive cHL (OR = 1.81, 95% CI 1.27-2.56) among current smokers, whereas risk of nodular sclerosis (OR = 1.09, 95% CI 0.90-1.32) and EBV-negative HL (OR = 1.02, 95% CI 0.72-1.44) was not increased.

CONCLUSION

These results support the notion of etiologic heterogeneity between HL subtypes, highlighting the need for HL stratification in future studies. Even if not relevant to all subtypes, our study emphasizes that cigarette smoking should be added to the few modifiable HL risk factors identified.

Epstein-Barr virus patterns in US Burkitt lymphoma tumors from the SEER residual tissue repository during 1979-2009

Burkitt lymphoma (BL) occurs at all ages, but the patterns of Epstein-Barr virus (EBV) positivity in relation to human immunodeficiency virus (HIV), immunoprofiles and age have not been fully explored. BL tissues from residual tissue repositories, and two academic centers in the United States were examined by expert hematopathologists for morphology, immunohistochemistry, MYC rearrangement, EBV-encoded RNA (EBER), and diagnosed according to the 2008 WHO lymphoma classification. Analysis was done using frequency tables, Chi-squared statistics, and Student's t-test. Of 117 cases examined, 91 were confirmed as BL. The age distribution was 26%, 15%, 19%, and 29% for 0-19, 20-34, 35-59, 60+ years, and missing in 11%. MYC rearrangement was found in 89% and EBER positivity in 29% of 82 cases with results. EBER positivity varied with age (from 13% in age group 0-19 to 55% in age group 20-34, and fell to 25% in age group 60+ years, p = 0.08); with race (56% in Blacks/Hispanics vs 21% in Whites/Asians/Pacific Islanders, p = 0.006); and by HIV status (64% in HIV positive vs 22% in HIV negative cases, p = 0.03). EBER positivity was demonstrated in about one-third of tumors and it was strongly associated with race and HIV status, and marginally with age-group.

A genome-wide integrative genomic study localizes genetic factors influencing antibodies against Epstein-Barr virus nuclear antigen 1 (EBNA-1)

Infection with Epstein-Barr virus (EBV) is highly prevalent worldwide, and it has been associated with infectious mononucleosis and severe diseases including Burkitt lymphoma, Hodgkin lymphoma, nasopharyngeal lymphoma, and lymphoproliferative disorders. Although EBV has been the focus of extensive research, much still remains unknown concerning what makes some individuals more sensitive to infection and to adverse outcomes as a result of infection. Here we use an integrative genomics approach in order to localize genetic factors influencing levels of Epstein Barr virus (EBV) nuclear antigen-1 (EBNA-1) IgG antibodies, as a measure of history of infection with this pathogen, in large Mexican American families. Genome-wide evidence of both significant linkage and association was obtained on chromosome 6 in the human leukocyte antigen (HLA) region and replicated in an independent Mexican American sample of large families (minimum p-value in combined analysis of both datasets is 1.4×10(-15) for SNPs rs477515 and rs2516049). Conditional association analyses indicate the presence of at least two separate loci within MHC class II, and along with lymphocyte expression data suggest genes HLA-DRB1 and HLA-DQB1 as the best candidates. The association signals are specific to EBV and are not found with IgG antibodies to 12 other pathogens examined, and therefore do not simply reveal a general HLA effect. We investigated whether SNPs significantly associated with diseases in which EBV is known or suspected to play a role (namely nasopharyngeal lymphoma, Hodgkin lymphoma, systemic lupus erythematosus, and multiple sclerosis) also show evidence of associated with EBNA-1 antibody levels, finding an overlap only for the HLA locus, but none elsewhere in the genome. The significance of this work is that a major locus related to EBV infection has been identified, which may ultimately reveal the underlying mechanisms by which the immune system regulates infection with this pathogen.

Detection of Epstein-Barr virus and genotyping based on EBNA2 protein in Mexican patients with hodgkin lymphoma: a comparative study in children and adults

BACKGROUND

Epstein-Barr virus (EBV) is a member of the Herpesviridae family and is associated with Hodgkin lymphoma (HL). Isolates of EBV are classified according to sequence variation in the latency genes such as Epstein-Barr virus nuclear antigen (EBNA). EBNA2 contains the most divergent locus and is classified into type 1 and type 2 or EBNA2A and EBNA2B, respectively. We compared the frequency of EBV and the distribution of EBNA genotypes in Mexican children and adults with HL.

PATIENTS AND METHODS

Lymph node biopsy specimens from children and adults with HL were embedded in paraffin. EBV was identified by LMP1 amplification and Epstein-Barr-encoded RNA EBER by in situ hybridization (ISH) and genotyped as EBNA2A or EBNA2B using nested polymerase chain reaction (PCR) and specific primers for the detection of subtype.

RESULTS

Sixty-six samples were obtained from 3 hospitals-42 (63%) from children and 24 (37%) from adults with HL. Thirty-two of the 42 samples (76.1%) were positive for EBV in children and 16 of 24 (66.6%) samples were positive in adults (P = .41). In both children and adults, EBV was found more frequently in male patients. Thirty-four of 48 cases could be typed (70.8%). EBNA2A was found in 7/21 (33.3%) children and in 4/13 (30.8%) adults (P = 1.0), and EBNA2B was found in 10/21 (47.6%) children and in 9/13 (69.2%) adults (P = .22). A mix of subtypes was found in 4/21 (19%) children.

CONCLUSION

EBV was found frequently in both children and adults with HL. EBNA2B was the most frequent subtype, and a high frequency of mixed subtypes was found in children.

Racial disparities in Hodgkin's lymphoma: a comprehensive population-based analysis

BACKGROUND

Racial disparity has been investigated in a number of cancers; however, there remains a comparative paucity of data in Hodgkin's lymphoma (HL).

PATIENTS AND METHODS

We examined time-, age-, and gender-specific incidence, disease characteristics, and survival across and within races for adolescent/adult HL (age 10-79 years) diagnosed during 1992-2007 in the SEER 13 registries.

RESULTS

A total of 15 662 HL cases were identified [11,211 non-Hispanic whites, 2067 Hispanics, 1662 blacks, and 722 Asian/Pacific Islanders (A/PI)]. Similar to whites, A/PIs had bimodal age-specific incidence, while blacks and Hispanics did not. Further, HL was significantly more common in Hispanics versus whites age>65 years (7.0/1×10(6) versus 4.5/1×10(6), respectively, P<0.01). By place of birth, US-born Hispanics and A/PIs age 20-39 years had higher incidence of HL versus their foreign-born counterparts (P<0.05), however, rates converged age>40 years. Interestingly, from 1992-1997 to 2003-2007, A/PI incidence rates increased >50% (P<0.001). Moreover, this increase was restricted to US-born A/PI. We also identified a number of disease-related differences based on race. Finally, 5-, 10-, and 15-year overall survival rates were inferior for blacks and Hispanics compared with whites (P<0.005 and P<0.001, respectively) and A/PI (P<0.018 and P<0.001, respectively). These differences persisted on multivariate analysis.

CONCLUSION

Collectively, we identified multiple racial disparities, including survival, in adolescent/adult HL.

A genome-wide meta-analysis of nodular sclerosing Hodgkin lymphoma identifies risk loci at 6p21.32

Nodular sclerosing Hodgkin lymphoma (NSHL) is a distinct, highly heritable Hodgkin lymphoma subtype. We undertook a genome-wide meta-analysis of 393 European-origin adolescent/young adult NSHL patients and 3315 controls using the Illumina Human610-Quad Beadchip and Affymetrix Genome-Wide Human SNP Array 6.0. We identified 3 single nucleotide polymorphisms (SNPs) on chromosome 6p21.32 that were significantly associated with NSHL risk: rs9268542 (P = 5.35 × 10(-10)), rs204999 (P = 1.44 × 10(-9)), and rs2858870 (P = 1.69 × 10(-8)). We also confirmed a previously reported association in the same region, rs6903608 (P = 3.52 × 10(-10)). rs204999 and rs2858870 were weakly correlated (r(2) = 0.257), and the remaining pairs of SNPs were not correlated (r(2) < 0.1). In an independent set of 113 NSHL cases and 214 controls, 2 SNPs were significantly associated with NSHL and a third showed a comparable odds ratio (OR). These SNPs are found on 2 haplotypes associated with NSHL risk (rs204999-rs9268528-rs9268542-rs6903608-rs2858870; AGGCT, OR = 1.7, P = 1.71 × 10(-6); GAATC, OR = 0.4, P = 1.16 × 10(-4)). All individuals with the GAATC haplotype also carried the HLA class II DRB1*0701 allele. In a separate analysis, the DRB1*0701 allele was associated with a decreased risk of NSHL (OR = 0.5, 95% confidence interval = 0.4, 0.7). These data support the importance of the HLA class II region in NSHL etiology.

Lymphoid malignancies in U.S. Asians: incidence rate differences by birthplace and acculturation

BACKGROUND

Malignancies of the lymphoid cells, including non-Hodgkin lymphomas (NHL), HL, and multiple myeloma, occur at much lower rates in Asians than other racial/ethnic groups in the United States. It remains unclear whether these deficits are explained by genetic or environmental factors. To better understand environmental contributions, we examined incidence patterns of lymphoid malignancies among populations characterized by ethnicity, birthplace, and residential neighborhood socioeconomic status (SES) and ethnic enclave status.

METHODS

We obtained data about all Asian patients diagnosed with lymphoid malignancies between 1988 and 2004 from the California Cancer Registry and neighborhood characteristics from U.S. Census data.

RESULTS

Although incidence rates of most lymphoid malignancies were lower among Asian than white populations, only follicular lymphoma (FL), chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), and nodular sclerosis (NS) HL rates were statistically significantly lower among foreign-born than U.S.-born Asians with incidence rate ratios ranging from 0.34 to 0.87. Rates of CLL/SLL and NS HL were also lower among Asian women living in ethnic enclaves or lower SES neighborhoods than those living elsewhere.

CONCLUSIONS

These observations support strong roles of environmental factors in the causation of FL, CLL/SLL, and NS HL.

IMPACT

Studying specific lymphoid malignancies in U.S. Asians may provide valuable insight toward understanding their environmental causes.

EBV in Hodgkin Lymphoma

Up to 40% of Hodgkin lymphoma (HL) cases are associated with the Epstein-Barr virus (EBV). Clonal viral genomes can be found in the HL tumor cells, the Hodgkin Reed-Sternberg cells (HRS). The latent infection results in expression of the viral oncogenes LMP1 and LMP2A which contribute to generate the particular phenotype of the HRS cells. EBV does not only undergo epigenetic changes of its genome during latency, but also induces epigenetic changes in the host genome. The presence of EBV may alter the composition and activity of the immune cells surrounding the HRS cells. EBV favours a Th1 reaction, but this attempt at a cell mediated immune response appears to be ineffective. The presence of EBV in HL is associated with several clinicopathological characteristics: It is more frequent in cases with mixed cellular histology, in males, in children and older adults, and in developing countries, while the young-adult onset HL of nodular sclerosis type in industrialized countries is typically EBV-negative. Countries in the Mediterranean area often show an intermediate epidemiological pattern. Recent studies suggest a genetic predisposition to develop EBV-associated HL. Circulating EBV-DNA may serve as a biomarker to monitor response to therapy, and eventually, EBV will become a target for therapeutic intervention also in HL.