Abstract Background: A previous International Lymphoma Epidemiology (InterLymph) Consortium evaluation of joint associations between five immune gene variants and autoimmune conditions reported interactions between B-cell response-mediated autoimmune conditions and the rs1800629 genotype on risk of B-cell non–Hodgkin lymphoma (NHL) subtypes. Here, we extend that evaluation using NHL subtype-specific polygenic risk scores (PRS) constructed from loci identified in genome-wide association studies of three common B-cell NHL subtypes. Methods: In a pooled analysis of NHL cases and controls of Caucasian descent from 14 participating InterLymph studies, we evaluated joint associations between B-cell–mediated autoimmune conditions and tertile (T) of PRS for risk of diffuse large B-cell lymphoma (DLBCL; n = 1,914), follicular lymphoma (n = 1,733), and marginal zone lymphoma (MZL; n = 407), using unconditional logistic regression. Results: We demonstrated a positive association of DLBCL PRS with DLBCL risk [T2 vs. T1: OR = 1.24; 95% confidence interval (CI), 1.08–1.43; T3 vs. T1: OR = 1.81; 95% CI, 1.59–2.07; P-trend (Ptrend) < 0.0001]. DLBCL risk also increased with increasing PRS tertile among those with an autoimmune condition, being highest for those with a B-cell–mediated autoimmune condition and a T3 PRS [OR = 6.46 vs. no autoimmune condition and a T1 PRS, Ptrend < 0.0001, P-interaction (Pinteraction) = 0.49]. Follicular lymphoma and MZL risk demonstrated no evidence of joint associations or significant Pinteraction. Conclusions: Our results suggest that PRS constructed from currently known subtype-specific loci may not necessarily capture biological pathways shared with autoimmune conditions. Impact: Targeted genetic (PRS) screening among population subsets with autoimmune conditions may offer opportunities for identifying those at highest risk for (and early detection from) DLBCL.
Occupational Pesticide Use and Risk of Non-Hodgkin Lymphoma
Abstract Background: Lipid traits have been inconsistently linked to risk of non-Hodgkin lymphoma (NHL). We examined the association of genetically predicted lipid traits with risk of diffuse large B-cell lymphoma (DLBCL), chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), and marginal zone lymphoma (MZL) using Mendelian randomization (MR) analysis. Methods: Genome-wide association study data from the InterLymph Consortium were available for 2,661 DLBCLs, 2,179 CLLs, 2,142 FLs, 824 MZLs, and 6,221 controls. SNPs associated (P < 5 × 10−8) with high-density lipoprotein (HDL, n = 164), low-density lipoprotein (LDL, n = 137), total cholesterol (TC, n = 161), and triglycerides (TG, n = 123) were used as instrumental variables (IV), explaining 14.6%, 27.7%, 16.8%, and 12.8% of phenotypic variation, respectively. Associations between each lipid trait and NHL subtype were calculated using the MR inverse variance–weighted method, estimating odds ratios (OR) per standard deviation and 95% confidence intervals (CI). Results: HDL was positively associated with DLBCL (OR = 1.14; 95% CI, 1.00–1.30) and MZL (OR = 1.09; 95% CI, 1.01–1.18), while TG was inversely associated with MZL risk (OR = 0.90; 95% CI, 0.83–0.99), all at nominal significance (P < 0.05). A positive trend was observed for HDL with FL risk (OR = 1.08; 95% CI, 0.99–1.19; P = 0.087). No associations were noteworthy after adjusting for multiple testing. Conclusions: We did not find evidence of a clear or strong association of these lipid traits with the most common NHL subtypes. While these IVs have been previously linked to other cancers, our findings do not support any causal associations with these NHL subtypes. Impact: Our results suggest that prior reported inverse associations of lipid traits are not likely to be causal and could represent reverse causality or confounding.
HLA Class I and II Diversity Contributes to the Etiologic Heterogeneity of Non-Hodgkin Lymphoma Subtypes
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.
Abstract LB-23: Meta-analysis of genome-wide association studies identifies multiple loci associated with chronic lymphocytic leukemia.
Abstract Despite limited discovery stages (<1,125 cases), genome-wide association studies (GWAS) have successfully identified 13 loci associated with risk of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL); however, these loci only explain a portion of the heritability. To identify additional genetic loci associated with CLL susceptibility, we conducted the largest meta-analysis of GWAS, to date, including 3,100 CLL cases and 7,667 controls of European ancestry from 25 independent studies genotyped on four different SNP microarrays. Association testing was conducted assuming a log-additive genetic model, adjusting for age, sex, and significant principal components. Meta-analyses were performed using the fixed effects inverse variance method based on the beta estimates and standard errors from each study. Promising loci were taken forward for replication in three additional studies totaling 788 cases and 4,872 controls. In the meta-analysis of both the discovery and replication studies, we conclusively identified ten independent SNPs in nine novel loci that reached genome-wide significance (P<5 x 10−8): 10q23.31 (FAS; P=1.22x10−14), 18q21.33 (BCL2; P=2.66x10−12 and P=7.76x10−11), 11p15.5 (C11orf21; P=2.15x10−10), 4q25 (LEF1; P=4.24x10−10), 2q33.1 (CASP8; P=2.50x10−9), 9p21.3 (CDKN2B-AS1; P=1.27x10−8), 18q21.32 (PMAIP1; P=2.51x10−8), 15q15.1 (BMF; P=2.71x10−10), and 2p22.2 (QPCT; P=1.68x10−8) as well as an independent signal at an established locus (2q13, ACOXL, P=2.08x10−18). We also found evidence for two additional promising loci that reached marginal genome-wide significance (P<2.0x10−7) at 8q22.3 (ODF1; P=5.40x10−8) and 5p15.33 (TERT; P=1.92x10−7). Although further studies are required, the proximity of five of the novel loci to genes involved in apoptosis suggests a possible unifying underlying biological mechanism. Together with the previously established loci, these genetic loci explain ~17% of the familial risk of CLL. Citation Format: Sonja I. Berndt, Christine F. Skibola, Vijai Joseph, Nicola J. Camp, Alexandra Nieters, Zhaoming Wang, Wendy Cozen, Alain Monnereau, Rachel S. Kelly, Silvia de Sanjose, Martha S. Linet, Elio Riboli, Paolo Vineis, Henrik Hjalgrim, James R. Cerhan, Stephen J. Chanock, Nathaniel Rothman, Susan L. Slager. Meta-analysis of genome-wide association studies identifies multiple loci associated with chronic lymphocytic leukemia. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr LB-23. doi:10.1158/1538-7445.AM2013-LB-23
InterLymph hierarchical classification of lymphoid neoplasms for epidemiologic research based on the WHO classification (2008): update and future directions
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.