Citations 24

Abstract 221: Inherited variants at 3q13.33 and 3p24.1 influences risk of diffuse large B-cell lymphoma

Cancer Research | August 17, 2018 | Volume: 78 | Issue: 13_Supplement | Pages: 221-221

10.1158/1538-7445.am2018-221

Abstract Background: We previously identified 5 SNPs at 4 susceptibility loci for diffuse large B-cell lymphoma (DLBCL) in individuals of European ancestry through a large genome-wide association study (Cerhan et al, Nat Gen 2014;46:1233-8); however, much of the heritability remains unexplained. To further elucidate genetic susceptibility to DLBCL, we sought to validate 2 loci at 3q13.33 and 3p24.1 that were suggestive in the original report. Methods: We selected two SNPs rs9831894 (3q13.33) and rs6773363 (3p24.1) for de novo replication from studies at the Mayo Clinic, MD Anderson, and Memorial Sloan Kettering. Logistic regression was used to estimate odds ratios (ORs), using a log-additive model, and adjusting for age, gender and significant eigenvectors for each genotyping center separately. For both SNPs, we then conducted a meta-analysis of all replication studies (n=3) and our original GWAS studies (n=4), encompassing in total 5662 cases and 9237 controls for rs9831894, and 5510 cases and 12,817 controls for rs6773363. Meta-analysis was conducted using the fixed-effects inverse variance method based on the β estimates and standard errors from each study. Results: In a meta-analysis of the 4 original GWAS scans (3856 cases and 7666 controls), rs9831894 (MAF=0.40) was associated with DLBCL risk (OR=0.84, P=4.52 x 10-9) and this replicated in a meta-analysis of the 3 studies with de novo genotyping (OR=0.80, P=4.17 x 10-5); the overall meta-analysis showed a strong association with DLBCL risk (OR=0.83, P=3.62 x 10-13). This locus maps near a plausible candidate gene, CD86, a protein coding gene and a member of the immunoglobulin superfamily that encodes a type I membrane protein. Binding of CD86 with cytotoxic T-lymphocyte-associated protein 4 negatively regulates T-cell activation and diminishes the immune response, while binding of CD86 with CD28 antigen is a costimulatory signal for activation of the T-cell. In a meta-analysis of the same 4 GWAS scans, rs6773363 (MAF=0.45) was tentatively associated with DLBCL risk (OR=1.17, P= 3.68 x 10-7) and this replicated in a meta-analysis of the studies with de novo genotyping (OR=1.27, P=3.78 x 10-7); the overall meta-analysis showed a strong association with DLBCL risk (OR=1.20, P=2.31 x 10-12). This locus also maps near a plausible candidate gene, eomesodermin (EOMES), a transcription factor crucial for embryonic development of the central nervous system and also putatively involved in T-cell differentiation in viral infection defense. Conclusion: In this follow-up analysis of our initial GWAS, we have identified two additional loci associated with risk of DLBCL, the most common lymphoma subtype. These loci provide additional evidence for the role of immune function in the etiology of DLBCL. Citation Format: Geffen Kleinstern, Michelle Hildebrand, Vijai Joseph, Sonja I. Berndt, Hervé Ghesquières, James McKay, Sophia S. Wang, Alexandra Nieters, David Cox, Alain Monnereau, Angela R. Brooks-Wilson, Qing Lan, Mads Melbye, Rebecca D. Jackson, Lauren R. Teras, Mark P. Purdue, Claire M. Vajdic, Demetrius Albanes, Anne Zeleniuch-Jacquotte, Simon Crouch, Yawei Zhang, Susan L. Slager, Xifeng Wu, Karin E. Smedby, Gilles Salles, Christine F. Skibola, Nathaniel Rothman, Stephen J. Chanock, James R. Cerhan. Inherited variants at 3q13.33 and 3p24.1 influences risk of diffuse large B-cell lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 221.
HLA Class I and II Diversity Contributes to the Etiologic Heterogeneity of Non-Hodgkin Lymphoma Subtypes

Cancer Research | May 7, 2018 | Volume: 78 | Issue: 14 | Pages: 4086-4096

10.1158/0008-5472.can-17-2900 | PMID 29735552

Abstract A growing number of loci within the human leukocyte antigen (HLA) region have been implicated in non-Hodgkin lymphoma (NHL) etiology. Here, we test a complementary hypothesis of “heterozygote advantage” regarding the role of HLA and NHL, whereby HLA diversity is beneficial and homozygous HLA loci are associated with increased disease risk. HLA alleles at class I and II loci were imputed from genome-wide association studies (GWAS) using SNP2HLA for 3,617 diffuse large B-cell lymphomas (DLBCL), 2,686 follicular lymphomas (FL), 2,878 chronic lymphocytic leukemia/small lymphocytic lymphomas (CLL/SLL), 741 marginal zone lymphomas (MZL), and 8,753 controls of European descent. Both DLBCL and MZL risk were elevated with homozygosity at class I HLA-B and -C loci (OR DLBCL = 1.31, 95% CI = 1.06–1.60; OR MZL = 1.45, 95% CI = 1.12–1.89) and class II HLA-DRB1 locus (OR DLBCL = 2.10, 95% CI = 1.24–3.55; OR MZL = 2.10, 95% CI = 0.99–4.45). Increased FL risk was observed with the overall increase in number of homozygous HLA class II loci (P trend < 0.0001, FDR = 0.0005). These results support a role for HLA zygosity in NHL etiology and suggests that distinct immune pathways may underly the etiology of the different NHL subtypes. Significance: HLA gene diversity reduces risk for non-Hodgkin lymphoma. Cancer Res; 78(14); 4086–96. ©2018 AACR.
Association of polygenic risk score with the risk of chronic lymphocytic leukemia and monoclonal B-cell lymphocytosis

Blood | April 19, 2018 | Volume: 131 | Issue: 23 | Pages: 2541-2551

10.1182/blood-2017-11-814608 | PMID 29674426

Key Points PRS, based on the known CLL loci, predicts CLL risk with high discrimination. This PRS predicts risk of monoclonal B-cell lymphocytosis, a precursor to CLL and a condition that has clinical impact beyond risk for CLL.
Lupus-related single nucleotide polymorphisms and risk of diffuse large B-cell lymphoma

Lupus Science & Medicine | November 13, 2017 | Volume: 4 | Issue: 1 | Pages: e000187

10.1136/lupus-2016-000187 | PMID 29214033

Objective Determinants of the increased risk of diffuse large B-cell lymphoma (DLBCL) in SLE are unclear. Using data from a recent lymphoma genome-wide association study (GWAS), we assessed whether certain lupus-related single nucleotide polymorphisms (SNPs) were also associated with DLBCL. Methods GWAS data on European Caucasians from the International Lymphoma Epidemiology Consortium (InterLymph) provided a total of 3857 DLBCL cases and 7666 general-population controls. Data were pooled in a random-effects meta-analysis. Results Among the 28 SLE-related SNPs investigated, the two most convincingly associated with risk of DLBCL included the CD40 SLE risk allele rs4810485 on chromosome 20q13 (OR per risk allele=1.09, 95% CI 1.02 to 1.16, p=0.0134), and the HLA SLE risk allele rs1270942 on chromosome 6p21.33 (OR per risk allele=1.17, 95% CI 1.01 to 1.36, p=0.0362). Of additional possible interest were rs2205960 and rs12537284. The rs2205960 SNP, related to a cytokine of the tumour necrosis factor superfamily TNFSF4, was associated with an OR per risk allele of 1.07, 95% CI 1.00 to 1.16, p=0.0549. The OR for the rs12537284 (chromosome 7q32, IRF5 gene) risk allele was 1.08, 95% CI 0.99 to 1.18, p=0.0765. Conclusions These data suggest several plausible genetic links between DLBCL and SLE.
Abstract 4267: Association of polygenic risk scores and family history with the risk of chronic lymphocytic leukemia (CLL)

Cancer Research | July 31, 2017 | Volume: 77 | Issue: 13_Supplement | Pages: 4267-4267

10.1158/1538-7445.am2017-4267

Abstract Background Thirty-four single nucleotide polymorphisms (SNPs) are associated with CLL risk to-date. Moreover, family history (FH) of hematological malignancy has been consistently found to be associated with CLL, with an 8.5-fold increased risk of CLL among first-degree relatives. However, there has not been an evaluation of the interactive effects among genetic factors and FH with CLL risk. Methods We pooled data from 8 CLL case-control studies within the InterLymph Consortium (1499 CLL cases and 2601 controls). We computed a polygenic risk score (PRS), a weighted average of the number of risk alleles across the 34 SNPs, with the weights being the log of the previously reported odds ratio (OR) for each SNP. We categorized the PRS by quintiles using the cutoff points based on the distribution of all InterLymph controls (N=8228). Self-reported FH data was available for 60% of cases and 73% of controls. FH was defined as any hematological malignancy in one or more first-degree relative. Logistic regression was used to estimate ORs and 95% confidence intervals (CIs) adjusted for age, sex, socioeconomic status and study. Results The median age at diagnosis of CLL was 63 years and median age of consent was 60 years in the controls. 67% were male in CLL cases and 57% in controls. As expected, FH was associated with CLL risk (OR= 2.14, CI= 1.60-2.86). The median PRS in the cases was 0.40 and in the controls was -0.36 with the frequency of CLL cases in the upper PRS quintile as 48% while in the lowest quintile only 6%. The PRS was strongly associated with CLL risk (OR= 2.90, CI= 2.35-3.56 for upper versus middle quintile). When jointly modeling FH with PRS, a significant interaction was observed (P=0.03). When stratifying by FH, the upper quintile of the PRS had an 11.8-fold (CI= 3.97-34.8) increased risk relative to those in the middle quintile in the FH+ strata, while a 3.11-fold (CI= 2.35-4.10) increased risk was observed in the FH- strata. Conclusions Our data suggest that the PRS has a strong association with CLL risk and this association varies with FH status. Among those with FH-, the risk of CLL was 3-fold for those with many inherited variants while the CLL risk was much higher than that in those with a FH+. Studies are needed to see whether this PRS stratifies risk among those with monoclonal B-cell lymphocytosis, the CLL precursor condition that affects 5-7% of the general population. Citation Format: Geffen Kleinstern, Silvia de Sanjosé, Nicola Camp, Claire M. Vajdic, Timothy G. Call, Mark Liebow, Dennis Robinson, Neil E. Kay, Julie Cunningham, Yolanda Benavente, Alain Monnereau, John Spinelli, James R. Cerhan, Susan L. Slager. Association of polygenic risk scores and family history with the risk of chronic lymphocytic leukemia (CLL) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4267. doi:10.1158/1538-7445.AM2017-4267
Abstract 1318: A genome-wide association study of Waldenström macroglobulinemia/lymphoplasmacytic lymphoma demonstrates association with chromosome 6

Cancer Research | July 31, 2017 | Volume: 77 | Issue: 13_Supplement | Pages: 1318-1318

10.1158/1538-7445.am2017-1318

Abstract Waldenström macroglobulinemia (WM) is a unique subset of lymphoplasmacytic lymphoma (LPL) that is defined by the presence of an LPL infiltrate in the bone marrow together with a monoclonal IgM protein in the serum. A somatic activating mutation, MYD88 L265P, occurs in 85+% of WM and in 25%-50% of patients with the precursor condition, IgM monoclonal gammopathy of undetermined significance (MGUS); however, germline MYD88 mutations have not been observed in WM patients, and the genetic basis for WM predisposition remains undefined. To identify novel WM susceptibility loci we conducted a two-stage genome-wide association study (GWAS) in over 450 WM cases and 4300 controls of European ancestry. Discovery (stage 1) included 217 WM cases (40% familial) and 3798 controls genotyped on the Illumina Omni Express or Illumina Omni2.5 platforms following standard quality control procedures. The genotyped data were imputed using the Haplotype Reference Consortium panel as a reference and analyzed using logistic regression. In stage 1, we identified three loci on chromosomes 6, 14 and 3 significantly associated (P<5.0x10-8) with risk of WM. Eleven promising SNPs in these and other suggestive loci (P<5.0x10-7) were selected for replication (stage 2) in 269 WM or LPL cases (4% familial) and 571 controls, and genotyping was conducted using standard methods on Taqman and Sequenom platforms or Sanger sequencing (1 SNP). Preliminary results confirm replication of the chromosome 6 locus. Stratification on familial status will illuminate the contribution of familial disease. These results will provide insight into the underlying genetic basis of WM susceptibility. Citation Format: Mary L. McMaster, Sonja I. Berndt, Shengchao A. Li, Susan Slager, Joseph Vijai, Charles C. Chung, Bin Zhu, Laurie Burdette, Brenda Birmann, Elizabeth E. Brown, James R. Cerhan, Karin Ekstrom-Smedby, Henrik Hjalgrim, Geffen Kleinstern, Brian K. Link, James McKay, Alain Monnereau, Lindsay M. Morton, Alexandra Nieters, Nathaniel Rothman, Christine F. Skibola, Alex Smith, Lauren R. Teras, Claire M. Vajdic, Roel Vermeulen, Belynda Hicks, Lynn R. Goldin, Neil E. Caporaso. A genome-wide association study of Waldenström macroglobulinemia/lymphoplasmacytic lymphoma demonstrates association with chromosome 6 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1318. doi:10.1158/1538-7445.AM2017-1318
Abstract LB-272: Genome-wide association study identifies multiple susceptibility loci for diffuse large B-cell lymphoma

Cancer Research | May 1, 2015 | Volume: 74 | Issue: 19_Supplement | Pages: LB-272-LB-272

10.1158/1538-7445.am2014-lb-272

Abstract Background: Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype and is clinically aggressive. Relatives of DLBCL patients are at elevated risk for DLBCL. In small genome-wide association studies (GWAS) in which all NHL subtypes were combined, no conclusive loci for DLBCL have been previously identified in individuals of European background, whereas a recent study conducted in East Asia identified a locus at 3q27. Methods: To identify genetic susceptibility loci for DLBCL, we conducted a meta-analysis of three new GWAS and one prior scan, totaling 3,857 DLBCL cases and 7,666 controls of European ancestry. Imputation was used to combine all the data using the 1000 Genomes Project release v3 and IMPUTE2. Based on these findings, we selected 6 promising SNPs for genotyping in an additional 202 cases and 3,431 controls, which were then included in a second meta-analysis. SNPTEST was used to estimate odds ratios (ORs), using the additive model and adjusting for age, gender and significant eigenvectors. Results: In our multi-stage analysis, five independent SNPs in four loci achieved genome-wide significance marked by rs116446171 at 6p25.3 (EXOC2; OR=2.33, P=1.60x10-20), rs13255292 and rs4733601 at 8q24.21 (PVT1; OR=1.23, P=4.86x10-12 and OR=1.18, P=1.63x10-8, respectively), rs2523607 at 6p21.33 (HLA-B; OR=1.34, 3.35x10-9) and rs2681416 at 3q13.33 (CD86; OR=1.20, P=6.04x10-9). The two 8q24.21 SNPs displayed minimal linkage disequilibrium (r2=0.03) and conditional analysis supported their independence. We did not observe a notable signal for a locus previously reported for DLBCL on 3q27 in East Asia, rs6773854 (OR=1.06, P=0.81). We estimated that common SNPs, including but not limited to the loci discovered in this study, explain approximately 16% of the variance for DLBCL risk overall. Discussion: The susceptibility locus at 6p25.3 maps near a plausible DLBCL candidate gene, EXOC2 (exocyst complex component 2), which interacts with Ral proteins, and disruption of the Ral-exocyst regulatory node impacts cellular and developmental processes associated with malignant transformation and progression. The two 8q24.21 variants are approximately 1Mb telomeric to the 8q24 region linked with multiple cancers including CLL. Both variants are positioned in close proximity to PVT1, which is a non-coding RNA implicated in the MYC activation, and MYC is known to be deregulated in some DLBCLs. The locus at 3q13.33 maps to CD86 (B7-2), a B-7 family member that along with CD80 (B7-1) is essential in cognate interactions between T- and B-lymphocytes; both play key roles in immunodeficiency, autoimmune diseases, and in anti-tumor immunity. Finally, we had multiple signals in the HLA region, the strongest of which was at 6p21.33 near HLA-B. HLA-B encodes the HLA class I heavy chain paralogue, which heterodimerizes with a light chain (β2 microglobulin) and plays a central role in presenting intracellularly processed self or foreign antigens to CD8+ cytotoxic T lymphocytes. Class I molecules have been extensively linked to the risk of a variety of immune-mediated diseases and cancers including DLBCL. Conclusions: These data provide substantial new evidence for genetic susceptibility to this B-cell malignancy, and point towards pathways involved in immune recognition and immune function in the pathogenesis of DLBCL. Citation Format: James R. Cerhan, Sonja I. Berndt, Joseph Vijai, Hervé Ghesquières, James McKay, Sophia S. Wang, Zhaoming Wang, Meredith Yeager, Alexandra Nieters, David Cox, Alain Monnereau, Christopher Flowers, Anneclaire J. De Roos, Angela R. Brooks-Wilson, Qing Lan, Gianluca Severi, Mads Melbye, Rebecca D. Jackson, Lauren R. Teras, Mark Purdue, Claire Vajdic, Demetrius Albanes, Kimberly A. Bertrand, Anne Zeleniuch-Jacquotte, Simon Crouch, Yawei Zhang, Paolo Vineis, Susan L. Slager, Karin E. Smedby, Gilles Salles, Christine F. Skibola, Nathaniel Rothman, Stephen J. Chanock, on behalf of the NHL GWAS Project. Genome-wide association study identifies multiple susceptibility loci for diffuse large B-cell lymphoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-272. doi:10.1158/1538-7445.AM2014-LB-272
Abstract 5072: Meta-analysis of genome-wide association studies identifies novel susceptibility loci for follicular lymphoma

Cancer Research | May 1, 2015 | Volume: 74 | Issue: 19_Supplement | Pages: 5072-5072

10.1158/1538-7445.am2014-5072

Abstract Background. Follicular lymphoma (FL) is an indolent B-cell malignancy with a variable clinical course that may transform to more aggressive forms of lymphoma. Previous modestly powered GWAS have reported multiple FL susceptibility loci in the HLA class I and II regions at 6p21.32-33, but novel non-HLA susceptibility loci and the genetic architecture of FL associations in the HLA region remain to be elucidated. Methods. We conducted the largest GWAS of FL to date consisting of 2,142 cases and 6,221 controls of European ancestry from 22 studies scanned on the Illumina OmniExpress. After imputation of common SNPs using IMPUTE2 and 1,000 Genomes Project v3 data, we conducted a meta-analysis of these data with two previous FL GWAS (n=586 cases, 1,537 controls) and replicated top hits in an additional 629 cases and 4,283 controls. Expression quantitative trait loci (eQTL) analyses were performed to evaluate the effects of associated variants on gene expression. Classical HLA allele imputations and stepwise regression analyses are underway to further characterize the HLA associations. Results. In the joint meta-analysis, the strongest association with FL risk was observed in the HLA region, where a large number of SNPs showed genome-wide significance (P<5x10-8 to P= 1.84x10-84), particularly in HLA class II at 6p21.32 where several HLA eQTLs were identified (P < 0.05). Outside HLA, we identified four novel loci associated with FL at 11q23.3 (CXCR5, rs4938573; P=3.14x10-15), 11q24.3 (ETS1, rs4937362; P=3.33x10-9), 3q13.33 (CD86, rs2681416; P=9.79x10-11) and 3q28 (LPP, rs6444305, P=2.55x10-8). These novel susceptibility loci were located in four biologically relevant genes involved in immune regulation: CXCR5 and its ligand, CXCL13, are involved in guiding B-cells into the B-cell zones of secondary lymphoid organs as well as T-cell migration. ETS1 is expressed in lymphoid cells and regulates immune cell function including differentiation, survival, and proliferation. CD86 and CD80 are classic members of the B7 costimulatory pathway that is important in maintaining immune function, suppression of autoimmunity and antitumor surveillance. LPP encodes a LIM domain-containing protein of the zyxin family and participates in cell adhesion, cell migration, proliferation and transcription dynamics. Conclusions. This large GWAS provides further support for the important role of common genetic variation in non-HLA genes and further evidence of the key role that HLA immune-regulatory genes play in the pathogenesis of FL. Citation Format: Christine F. Skibola, Sonja I. Berndt, James R. Cerhan, Zhaoming Wang, Joseph Vijai, Lucia Conde, Paul de Bakker, Sophia S. Wang, Claire M. Vajdic, Brenda M. Birmann, Susan L. Slager, James McKay, Paige M. Bracci, Alexandra Nieters, Qing Lan, Angela R. Brooks-Wilson, Martha S. Linet, Demetrius Albanes, John J. Spinelli, Roel C.H. Vermeulen, Mark P. Purdue, Meredith Yaeger, Lauren R. Teras, Silvia de Sanjose, Alain Monnereau, Simon Crouch, Jia Nee Foo, Henrik Hjalgrim, Gianluca Severi, Brian K. Link, Kimberly A. Bertrand, Yawei Zhang, Karin E. Smedby, Stephen J. Chanock, Nathaniel Rothman, NHL GWAS Consortium. Meta-analysis of genome-wide association studies identifies novel susceptibility loci for follicular lymphoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5072. doi:10.1158/1538-7445.AM2014-5072
PRRC2A and BCL2L11 gene variants influence risk of non-Hodgkin lymphoma: results from the InterLymph consortium

Blood | October 10, 2012 | Volume: 120 | Issue: 23 | Pages: 4645-4648

10.1182/blood-2012-05-427989 | PMID 23047821

AbstractMany common genetic variants have been associated with non-Hodgkin lymphoma (NHL), but individual study results are often conflicting. To confirm the role of putative risk alleles in B-cell NHL etiology, we performed a validation genotyping study of 67 candidate single nucleotide polymorphisms within InterLymph, a large international consortium of NHL case-control studies. A meta-analysis was performed on data from 5633 B-cell NHL cases and 7034 controls from 8 InterLymph studies. rs3789068 in the proapoptotic BCL2L11 gene was associated with an increased risk for B-cell NHL (odds ratio = 1.21, P random = 2.21 × 10−11), with similar risk estimates for common B-cell subtypes. PRRC2A rs3132453 in the HLA complex class III region conferred a reduced risk of B-cell NHL (odds ratio = 0.68, P random = 1.07 × 10−9) and was likewise evident for common B-cell subtypes. These results are consistent with the known biology of NHL and provide insights into shared pathogenic components, including apoptosis and immune regulation, for the major B-cell lymphoma subtypes.
InterLymph hierarchical classification of lymphoid neoplasms for epidemiologic research based on the WHO classification (2008): update and future directions

Blood | August 11, 2010 | Volume: 116 | Issue: 20 | Pages: e90-e98

10.1182/blood-2010-06-289561 | PMID 20699439

Abstract After publication of the updated World Health Organization (WHO) classification of tumors of hematopoietic and lymphoid tissues in 2008, the Pathology Working Group of the International Lymphoma Epidemiology Consortium (InterLymph) now presents an update of the hierarchical classification of lymphoid neoplasms for epidemiologic research based on the 2001 WHO classification, which we published in 2007. The updated hierarchical classification incorporates all of the major and provisional entities in the 2008 WHO classification, including newly defined entities based on age, site, certain infections, and molecular characteristics, as well as borderline categories, early and “in situ” lesions, disorders with limited capacity for clinical progression, lesions without current International Classification of Diseases for Oncology, 3rd Edition codes, and immunodeficiency-associated lymphoproliferative disorders. WHO subtypes are defined in hierarchical groupings, with newly defined groups for small B-cell lymphomas with plasmacytic differentiation and for primary cutaneous T-cell lymphomas. We suggest approaches for applying the hierarchical classification in various epidemiologic settings, including strategies for dealing with multiple coexisting lymphoma subtypes in one patient, and cases with incomplete pathologic information. The pathology materials useful for state-of-the-art epidemiology studies are also discussed. We encourage epidemiologists to adopt the updated InterLymph hierarchical classification, which incorporates the most recent WHO entities while demonstrating their relationship to older classifications.