Ghesquières, Hervé

Abstract Background Relatively few studies have evaluated the role of host (germline) genetics in predicting outcome in diffuse large B-cell lymphoma (DLBCL), and of these, most were small candidate gene studies without replication and/or from the pre-R-CHOP era. We report the first genome-wide association study (GWAS) of outcome in DLBCL patients treated with rituximab and anthracycline-based chemotherapy. We used two independent studies for discovery, and validated the results in two additional independent studies. Methods In the discovery phase, we conducted a meta-analysis of two GWAS studies of DLBCL patients treated with rituximab and anthracycline-based chemotherapy, the first study as part of the prospective clinical trials of the LNH2003B program (N=540) of the Lymphoma Study Association (LYSA) and the second as part of the Molecular Epidemiology Resource (N=316), a prospective observational study from the University of Iowa/Mayo Clinic Lymphoma Specialized Program of Research Excellence (SPORE). Genotyping for the GWAS was performed using the Illumina 610 (LYSA) and 660 Quad (SPORE) BeadArrays (Illumina, San Diego, USA). HapMap2 was used to impute additional SNPs. Association testing was conducted assuming a log-additive genetic model and using Cox regression analyses. We calculated the hazard ratios (HRs) and 95% CIs for event-free survival (EFS), with adjustment for age, sex and age-adjusted IPI. The two studies were then combined using the fixed effects inverse variance method based on the beta estimates and standard errors from each study. From the meta-analysis, 89 SNPs were selected for validation, based on a minor allele frequency (MAF) >0.05 and LD pattern for multiple SNPs from the same region. Validation cohorts were an independent set of DLBCL patients from the SPORE (SPORE-2, N=366) and DLBCL patients from the prospective GOELAMS 075 phase III study (N=294), and validation genotyping was conducted using the Illumina VeraCode platform. We then conducted a meta-analysis of the 4 studies. We report SNPs with both a statistical significance of p<5x10-6 and effect sizes in the same direction across the 4 studies in the meta-analysis. For the latter SNPs, we also report the results for overall survival (OS), adjusted for age, sex and age-adjusted IPI. Results In the final meta-analysis of all four studies for the prediction of EFS, the top SNP was rs7765004 (MAF=0.30; HR=1.45; p=9.7 x 10-8) in the 6q21 region, which is near the MARCKS (myristoylated alanine-rich protein kinase C substrate) and HDAC2 genes. MARCKS encodes for a protein involved in cell mobility, while HDAC2 belongs to the histone deacetylase family. Additional SNPs from this region included rs6918103 (MAF=0.25; HR=1.38; p=7.6 x 10-6), which marks an EZH2 histone binding site, and rs11969684 (MAF=0.12; HR=1.43; p=3.3 x 10-5). The next hit was rs7712513 (MAF=0.31; HR=1.40; p=3.2 x 10-7), which is near arginine-fifty homeobox pseudogene 1 (ARGFXP1) on chromosome 5q23.2. This was followed by a region on chromosome 8q13.3, with the SNP rs9298183 (MAF=0.29; HR=1.41; p=1.4 x 10-6) from LOC100132891 showing the strongest association, along with 3 other SNPs from this region (rs2035376, rs6472637, and rs1600797; all p<5 x 10-6). These SNPs are near the musculin gene (MSC) a transcriptional repressor of E2A frequently silenced by promoter methylation in DLBCL. Finally, rs2253986 (MAF=0.27; HR=1.39; p=3.4 x 10-6) at chromosome 16q12.2, along with rs2253971 and rs6499810, were associated with EFS. These SNPs are located in CES5A (carboxylesterase 5A), which encodes a member of the carboxylesterase family. The family members are responsible for the hydrolysis or transesterification of various xenobiotics. The top SNPs associated with EFS also predicted OS, including rs7765004 (HR=1.41; p=1.2 x 10-5), rs7712513 (HR=1.39; p=8.4 x 10-6), rs9298183 (HR=1.36; p=3.5 x 10-5), and rs2253986 (HR=1.35; p=5.2 x 10-5). Conclusions Although our top SNPs on did not reach genome-wide significance (p<5x10-8), they showed clear consistency across the four large prospective studies and predicted both EFS and OS independently of IPI. The strongest findings were from loci on 6q21, 8q13.3, 5q23.2, and 16q12.2, and several genes from these regions are involved in methylation and xenobiotic metabolism, supporting a role for host genetic variation in these pathways in DLBCL prognosis. Disclosures: No relevant conflicts of interest to declare.

Abstract We have recently reported that event-free survival at 24 months from diagnosis (EFS24) is a robust endpoint for assessment of disease related outcome for newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL) treated with anthracycline-based immunochemotherapy (IC). Patients who achieve EFS24 following IC have a subsequent overall survival that is equivalent to the age and sex matched general population. The IPI was developed in the pre-rituximab era using OS/EFS endpoints. While the IPI is associated with outcome in the IC era, the original survival estimates for the IPI risk groups are outdated. The IPI is also a discrete risk classifier, with only 6 possible groups. Here we remodel the IPI using EFS24 as the endpoint in a large international cohort of patients treated with IC. This model provides an individual level 0-100% risk of failing to achieve EFS24 for each patient and can be used for patient prognosis, treatment stratification, and risk assessment. Methods Newly diagnosed DLBCL patients treated with immunochemotherapy from the University of Iowa/Mayo Clinic SPORE Molecular Epidemiology Resource, NCCTG N0489 clinical trial, GELA LNH2003B program, and a Lyon, France based hospital registry were included in the original EFS24 study. Patients with a relapse, progression, unplanned re-treatment, or death due to any cause within 730 days of diagnosis were considered a failure for the EFS24 endpoint. Patients alive and progression/relapse free at 730 days from diagnosis with no subsequent treatment following initial IC were considered a success for the EFS24 endpoint. Variables selected for potential model inclusion were the IPI components (age, stage, ECOG PS, number of extranodal sites, and LDH), as well as standard clinical variables typically reported in studies of DLBCL: presence of B-symptoms, bone marrow involvement, bulky disease (>10 cm), and sex. The IPI24, a prognostic model for EFS24, was developed using logistic regression models. Model building began by fitting the classic IPI score (0-5), then allowing individual IPI variables to carry different model weights and number of categories, followed by dropping insignificant variables, finally adding any additional significant variables. Model performance was assessed using bias corrected c-statistics, AIC, and R2 values. Model selection was done using the complete case set with multiple imputation on the full dataset used to refine parameter estimates for the final model. Results 1596 total patients were available for modeling. The median age was 62 (range 18-93) and 53% were male; 33% were IPI 0-1, 25% were IPI 2, 25% were IPI 3, and 17% were IPI of 4-5. The failure rate for achieving EFS24 was 29%. All variables but sex (p=0.33) were univariately associated with EFS24 (p<6.4x10-5). The original IPI had good prognostic ability for EFS24 (c=0.696, p=2.2x10-32). Allowing multiple categories for ECOG PS, stage, and age (continuous) improved model fit and prognostic ability (c=0.727). The number of extranodal sites was not significant when IPI variables were modeled separately and was removed from the model. Sex and bulky disease were additional significant variables when added to the model. Thus, the final IPI24 model contained the following risk predictors: male sex, ECOG PS (0 vs. 1 vs 2 vs 3-4), stage (I vs. II, vs. III vs. IV), LDH (elevated vs. normal range), bulky disease > 10cm, and age (continuous). This model resulted in improved fit and prognostic ability (c=0.749) over the standard IPI (c=0.696, bootstrap p<0.001). Model validation was performed on an additional 158 patients from the SPORE MER and showed good concordance (c=0.697). Additional validation is planned in a larger set of independent patients. Conclusion The IPI24, generated using standard clinical variables, yields an individual risk prediction for failing to achieve EFS24 following IC for treatment of DLBCL. The IPI24 has superior prognostic ability to the standard IPI and can be implemented in the clinic using a nomogram or as a simple electronic application. Disclosures: No relevant conflicts of interest to declare.

Abstract Background: Patients (pts) with DLBCL who receive first-line anthracycline based immunochemotherapy and remain in remission at 2 years have excellent outcomes with overall survival (OS) in one study that was comparable to the age and sex matched general population in cohorts from the US and France (Maurer et al, JCO 2014). To evaluate whether these findings are robust and generalizable, we assessed OS stratified by progression-free survival at 24 months (PFS24) using individual patient data from pts with DLBCL enrolled in 14 multi-center, international randomized clinical trials as part of the SEAL consortium. Methods: Central data alignment was performed by the SEAL statistics and data center. All enrolled patients treated with rituximab-containing anthracycline-based immunochemotherapy as part of initial induction therapy were included in this analysis using an intent-to-treat approach. PFS was defined as time from initiation of first-line therapy to progression or death. PFS24 was defined as being alive and progression-free 24 months (731 days) after initiation of therapy. Overall survival from PFS24 was defined as time from achieving PFS24 until death due to any cause. OS was compared to each patient's age-, sex-, and country- matched general population using expected survival and standardized mortality ratios (SMR). Country-level population rate tables were obtained from www.mortality.org where available. A per-study average rate table was used when country information was unavailable. OS beyond 9 years from treatment initiation was only available the time of analysis from two trials (13% of cohort) and thus follow-up from PFS24 was restricted to the first 7 years after PFS24 for this analysis. Results: Fourteen studies with 7975 patients were included in the SEAL database. 5853 (73%) received rituximab as part of induction therapy and used in this analysis. Median age was 62 years (range 18-92) with 56% >60 years, 54% were male, 57% had elevated LDH, 63% had stage III/IV disease, 13% had ECOG PS 2-4, and IPI was 0-1 in 36%, 2 in 25%, 3 in 23%, and 4-5 in 16%. At a median follow-up of 4.4 years, 1337 (23%) had disease progression, 1489 patients (25%) had died, and 5101 patients were evaluable for PFS24. 1423 (28%) of evaluable patients failed to achieve PFS24. These patients had poor outcomes after progression with median OS of 7.2 months (95% CI 6.8-8.1), 5-year OS of 19%, and SMR of 32.1 (95% CI: 30.0-34.4). Outcome was excellent (median unreached) in the 3678 patients who were progression-free at 24 months, with subsequent OS after achieving PFS24 approaching the age and sex matched general population (Figure). The observed vs. expected OS at 3, 5, and 7 years after achieving PFS24 was 93.1% vs. 94.4%, 87.6% vs. 89.5%, and 80.0% vs. 83.7%, respectively, the SMR was 1.22 (95% CI: 1.09-1.37). In subset analyses examining pts achieving PFS24, adverse prognostic characteristics at baseline (elevated LDH, advanced stage, ECOG PS 2-4, high IPI) were associated with greater decrement in OS from the general population based expected survival (Table). Conclusions: PFS24 from the start of initial therapy stratifies DLBCL pts into populations with distinct outcomes. DLBCL pts treated with rituximab containing anthracycline-based immunotherapy on large randomized clinical trials who are alive without progression at 24 months from start of initial therapy have excellent outcomes with survival that is marginally lower but clinically indistinguishable from the age-, sex-, and country-matched background population for at least 7 years after achieving PFS24. Further follow-up time will be needed to assess any long-term impact of late relapse and survivorship issues in this population. Table Table. Figure Figure. Disclosures Shi: Mayo Clinic: Employment. Cunningham:Amgen: Research Funding; Astra-Zeneca: Research Funding; Bayer: Research Funding; Celgene: Research Funding; Merrimack: Research Funding; Medimmune: Research Funding. Seymour:AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Speakers Bureau; Genentech: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Jaeger:Roche: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Haioun:Sandoz: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees. Ghesquieres:Mundipharma: Consultancy; Roche France: Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees. Merli:Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Teva Pharmaceuticals Industries: Membership on an entity's Board of Directors or advisory committees. Herbrecht:Servier: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Cell Therapeutics, Inc: Membership on an entity's Board of Directors or advisory committees. Flament:Celgene: Employment, Equity Ownership. Fu:Celgene: Employment, Equity Ownership. Flowers:Gilead: Consultancy, Research Funding; Roche: Consultancy, Research Funding; Acerta: Research Funding; ECOG: Research Funding; Mayo Clinic: Research Funding; Pharmacyclics, LLC, an AbbVie Company: Research Funding; Millenium/Takeda: Research Funding; Infinity: Research Funding; TG Therapeutics: Research Funding; Genentech: Consultancy, Research Funding; NIH: Research Funding; AbbVie: Research Funding. Ou:Mayo Clinic: Employment. Sargent:Celgene: Research Funding. Coiffier:MorphoSys: Consultancy; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees.

Abstract Background OSis the gold standard primary efficacy endpoint for evaluating treatment strategies for DLBCL. Because current standard of care first-line regimens with rituximab plus chemotherapy produce median OS > 8 years, an endpoint assessed earlier would accelerate the evaluation of new therapies and potentially allow patients (pts) to more rapidly benefit from study results. The SEAL group formally evaluated PFS as a surrogate endpoint for OS in first-line therapy for DLBCL. Methods Through a systematic literature search and input from lymphoma experts on the SEAL committee, we identified multicenter, randomized controlled clinical trials that evaluated active treatment and enrolled at least 100 pts with previously untreated DLBCL or aggressive non Hodgkin lymphoma by WHO/REAL classification, published after January 1, 1995. Studies which enrolled only early stage (I or II) pts and studies that could not provide individual pt data (IPD) were excluded from surrogacy analysis. Potential surrogate candidates for OS included: 1) PFS, defined as the time from initiation of induction treatment to progressive disease, relapse or death due to any cause, and 2) PFS rate at 24 months after initiation of induction treatment (PFS24). These endpoints were derived consistently for all studies based on IPD. Surrogacy was evaluated by the correlation between surrogate candidates and OS. Pt-level correlation was measured by the rank correlation coefficient (ρ) and global odds ratio for PFS and PFS24, respectively, estimated by the Copula model. Trial-level correlation was evaluated by the correlation between trial-specific treatment effects on surrogate candidates and OS with two commonly used trial-level R2s: R2WLS (Sargent et al JCO 2005) and R2Copula (Burzykowski et al J R Stat Soc C 2001 and Burzykowski et al J R Stat Soc A 2004). For the R2 measures, a value closer to 1 indicates a stronger correlation. We pre-specified that if either trial-level R2 was >=0.80 and its 95% confidence interval (CI) excluded 0.60, the candidate would meet criteria for surrogacy. Results Thirteen of 14 studies collected to date in the SEAL database met all inclusion criteria. IPD for 7507 pts (median age 63 years, 54% male, 46% ECOG performance status 0, 8% IPI 0, 50% IPI 1-2, 64% stage III/IV, median follow-up time of 52 months) were analyzed. Among 13 studies, one tested maintenance treatment only and two tested both induction and maintenance regimens. One study included four treatment arms. Thus at the trial level, 17 two-arm comparisons were formed: 14 comparisons comparing induction regimens and 3 comparing maintenance; 15 comparisons involved rituximab. Longer PFS was highly correlated with longer OS at the pt level (ρ= 0.85, 95% CI 0.84-0.86), as was PFS24 (Global odds ratio = 61.1, 95% CI 52.6-69.6). The Table shows trial-level correlations, and the Figure shows trial-level association between estimated treatment effects (log(HR) [hazard ratio]) on PFS and OS. The trial-level correlation between PFS and OS was strong and met the pre-specified surrogacy criteria, with R2WLS of 0.83 (95% CI 0.58-0.94) and R2Copula of 0.85 (95% CI 0.72-0.99). Sensitivity analyses including only comparisons including rituximab or only induction regimens showed consistent results. The overall trial-level correlation between PFS24 and OS was reduced slightly, with R2WLS of 0.77 (95% CI 0.49-0.92) and R2Copula of 0.78 (95% CI 0.59-0.96). Performance of PFS24 was improved when restricting analysis to only including induction studies (see table). Conclusion This large IPD pooled-analysis demonstrates that PFS duration met the pre-specified criteria as a robust surrogate endpoint for OS, and can be considered as a surrogate endpoint for OS for frontline DLBCL trials evaluating immunochemotherapy. The earlier endpoint of PFS24 showed promise as a potential surrogate and further validation is warranted. Figure Figure. Disclosures Shi: Mayo Clinic: Employment. Flowers:Millenium/Takeda: Research Funding; TG Therapeutics: Research Funding; Pharmacyclics, LLC, an AbbVie Company: Research Funding; Gilead: Consultancy, Research Funding; NIH: Research Funding; Mayo Clinic: Research Funding; ECOG: Research Funding; Acerta: Research Funding; Infinity: Research Funding; AbbVie: Research Funding; Roche: Consultancy, Research Funding; Genentech: Consultancy, Research Funding. Ou:Mayo Clinic: Employment. Cunningham:Merrimack: Research Funding; Celgene: Research Funding; Bayer: Research Funding; Astra-Zeneca: Research Funding; Amgen: Research Funding; Medimmune: Research Funding. Pfreundschuh:Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Spectrum: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Seymour:AbbVie Inc.: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Genentech: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Gilead: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees. Jaeger:Roche: Honoraria, Research Funding; Celgene: Honoraria, Research Funding. Haioun:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sandoz: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees. Ghesquieres:Mundipharma: Consultancy; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Roche France: Research Funding. Merli:Teva Pharmaceuticals Industries: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees. Herbrecht:Cell Therapeutics, Inc: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Servier: Membership on an entity's Board of Directors or advisory committees. Flament:Celgene: Employment, Equity Ownership. Fu:Celgene: Employment, Equity Ownership. Coiffier:MorphoSys: Consultancy, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celltrion: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees. Sargent:Celgene: Research Funding.

Abstract Abstract 1540 Background: Diffuse Large B-cell Lymphoma (DLBCL) is the most common lymphoma in the western world. Outcomes have improved with the standard initial therapy of rituximab and anthracyline based chemotherapy (immunochemotherapy). However, 20–40% of patients will either fail to achieve remission or relapse following initial immunochemotherapy. Most relapses occur early, and long-term outcome of relapsed/refractory patients is generally poor despite salvage regimens and stem cell transplant. Traditionally, studies for DLBCL have been evaluated using progression-free and/or overall survival. However, the event rate in DLBCL slows significantly approximately 12–18 months after diagnosis, and late events are often due to competing (non-DLBCL related) risks, especially in older patients. Here we examine outcome of DLBCL patients based on their event status at 12 months. Methods: Newly diagnosed DLBCL patients were prospectively enrolled in the University of Iowa/Mayo Clinic Lymphoma SPORE Molecular Epidemiology Resource (MER). Clinical data were abstracted from medical records using a standard protocol. Patients were actively followed for events (progression, re-treatment, or death due to any cause) and overall survival (OS). Event-free status at 12 months after diagnosis (EFS12) was assessed as a dichotomous variable. Cause of death was determined by medical record and death certificate review using prospectively determined definitions. Expected survival was based on age and sex matched survival using the Minnesota population death rates. Confirmation cohorts were from a Lyon, France hospital based registry and NCCTG clinical trial N0489. Results: 680 patients with newly diagnosed DLBCL and treated with rituximab + anthracycline based chemotherapy were enrolled in the MER from 2002 to 2009. The median age was 62 years (range 18–92). 53% were male. At a median follow-up of 59 months (range 8–116), 266 patients (39%) had an event and 188 patients (28%) died. 162 patients (24%) had an event in the first 12 months after diagnosis, comprising 60% of all events. Patients with an event in the first 12 months had poor survival with death almost exclusively due to disease (Figures 1a, 2a). In contrast, patients who were event-free at 12 months had comparable survival to the age and sex matched general population (Figure 2b) and were more likely to die of other causes than DLBCL (Figure 1b). Overall survival rates by EFS12 status were validated in patients from a French hospital-based registry (N=265) and the NCCTG N0489 clinical trial (N=87) with additional replication studies underway. Conclusions: DLBCL patients who are event-free at 12 months after diagnosis have an excellent prognosis with an overall survival similar to that of an age- and sex- matched general population and are more likely to die of other causes than DLBCL. This finding has implications for clinical management, new clinical trials, and follow-up testing in this patient population. In contrast, patients with an event within the first 12 months after diagnosis have a poor prognosis with almost all deaths secondary to DLBCL. EFS status at 12 months identifies patients with poor outcomes due to disease. This can be utilized as an endpoint in biologic studies and clinical trials to address early treatment failures. EFS status at 12 months should be incorporated into prognostic models to identify high risk patients in newly diagnosed DLBCL. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 149 Background. There are few established factors that predict risk of follicular lymphoma (FL) transformation, and only two studies have evaluated the role of germline genetic variation and risk of transformation. One study reported an association of a BCL6 SNP (397C>G) with risk of transformation, and a second study reported an association with rs6457327, which is in the HLA region of 6p21. This study evaluated the risk of FL transformation in the modern treatment era with germline SNPs that were previously reported to be associated with FL transformation (BCL6SNPs and rs6457327), along with SNPs (N=45) previously associated with either risk of FL or FL prognosis. Methods. Newly diagnosed FL patients were prospectively enrolled from 2002–2009 into the Molecular Epidemiology Resource of the University of Iowa/Mayo Clinic Lymphoma SPORE. Peripheral blood for genotyping was collected at enrollment, and clinical and treatment data were abstracted from medical records. All patients were actively followed for disease progression, retreatment, transformation and death. For this analysis, only FL patients with grade I-IIIa were included. Patients with composite DLBCL, FL grade IIIb, or other evidence of transformation at diagnosis were excluded. Transformation was based on either 1) biopsy confirmation of FL grade IIIb, DLBCL, or higher grade B-cell lymphoma; or 2) clinical indicators of transformation based on the published literature, including sudden rise in LDH, rapid discordant localized nodal growth, new involvement of unusual extranodal sites, new B-symptoms, or hypercalcemia. Genotyping was conducted using a custom Illumina iSelect panel. Cox regression was used to estimate Hazard Ratios (HRs) and 95% confidence intervals (CI) for individual SNPs with time to transformation, with death modeled as a competing risk. Each SNP was modeled with the most prevalent homozygous genotype used as the reference group, and each SNP was modeled as having a log-additive (per minor allele) effect in the regression model. An ordinal test was used to assess the trend, and p<0.05 was considered statistically significant. Results. There were 631 newly diagnosed grade I-IIIa FL patients, of whom 532 had DNA and were successfully genotyped. The median age at diagnosis was 60 years (range 23–93) and 53% were male. FLIPI distribution was 42% 0–1, 34% 2 and 24% 3–5. Initial therapies included observation (32%), rituximab (R) monotherapy (13%), alkylator-based chemotherapy +/− R (20%), and anthracycline-based chemotherapy +/− R (19%). At a median of 59 months of follow-up (range, 11–110), 58 patients died, 254 had an event (death, progression or retreatment) and 54 patients (10%) transformed. Transformation was biopsy proven in 43 of the 54 patients (80%). The SNP rs6457327 on chromosome 6p that was previously reported to be associated with transformation was positively associated with risk of transformation in our data (HR=1.40; 95%CI 0.97–2.04; p=0.07), although this association was weaker but still consistent with the prior report. Further, we evaluated additional typed SNPs from the HLA region of 6p, and found additional associations (p<0.05) with HLA-DRA (3 SNPs), HLA-DQA2 (2 SNPs), HLA-DOA (2 SNPs) and HLA-DPB1/HLA-DPA2 (2 SNPs), of which rs10484569 from HLA-DPB1/HLA-DPA2 was the most strongly associated with risk of transformation (HR=3.01; 95%CI 1.48–6.09; p=0.002). None of the BCL6 or other previously reported risk SNPs were associated with transformation. Of the SNPs previously associated with FL prognosis, only the FCGR2A rs1801274 (HR=1.41; 95%CI 0.94–2.10; p=0.09) and CD46 (CD46 molecule, complement regulatory protein) rs2466571 (HR=1.72; 95%CI 1.16–2.55; p=0.007) were associated with risk of transformation. For CD46, one additional SNP (rs2796269) was also associated with transformation (HR=0.61; 95%CI 0.40–0.95; p=0.03). Further adjustment for FLIPI score and treatment (observation versus all other) did not alter these associations. Conclusions. The previously reported association of rs6457327 with risk of transformation in the modern treatment era was replicated. In addition, several HLA loci and two FL prognosis SNPs were linked to transformation risk. The remaining published FL risk or prognosis SNPs were not associated with transformation. Our results support a role for germline genetic variation in the HLA region, FCRGR2A and CD46 in transformation of FL. Disclosures: No relevant conflicts of interest to declare.

Abstract Background: Follicular lymphoma (FL) is an indolent lymphoma generally considered incurable with current standard therapies. Recent advances have resulted in prolongation of overall survival (OS) for patients with FL such that death from competing causes may now limit the mortality impact of FL in some patient groups. Identification of patients for whom FL related mortality is expected to be minimal, or conversely those at high risk of disease related mortality, is highly clinically relevant. We recently reported (Maurer et al, JCO 2014;32:1066-73) that event-free survival (EFS) at 24 months from diagnosis is a robust endpoint for disease related outcome in patients with diffuse large B cell lymphoma (DLBCL). Here we use the same approach to assess if landmark timepoints of EFS can stratify subsequent OS in FL. Methods: All newly diagnosed grade 1-3a FL patients enrolled on the University of Iowa/Mayo Clinic Lymphoma SPORE Molecular Epidemiology Resource (MER) from 2002-2011 were eligible. Patients with grade 3b FL, transformation, or presence of DLBCL at diagnosis were excluded. EFS was defined as time from diagnosis to progression, relapse, re-treatment, or death due to any cause. EFS12 was defined based on EFS status 12 months after date of diagnosis; we also assessed EFS at 24 months. OS was defined as time from a specific timepoint (diagnosis, event, or EFS12) until death due to any cause. OS was compared to age and sex matched survival in the general US population using an expected survival approach and standardized mortality ratios (SMR) and 95% confidence intervals (CI). Outcomes were examined in all patients as well as selected subsets defined by initial treatment. Replication was performed using a Lyon, France hospital registry of newly diagnosed grade 1-3a FL patients enrolled from 2002-2010 with survival compared to French population data. Results: 936 patients with grade 1-3a FL were eligible from the MER. The median age at diagnosis was 60 years (range 19-91) and 53% were male. 86% had grade 1-2 disease and 14% grade 3a disease. 23% had high-risk disease (FLIPI score ≥3). 347 (37%) were initially treated with alkylator or anthracyline based immunochemotherapy (IC), 113 (12%) rituximab monotherapy (RM), and 318 (34%) were initially observed; the remaining patients received radiation for limited stage disease (8%), chemotherapy without rituximab (4%), or other therapy (5%). At a median follow-up of 59 months (range 1-131), 403 patients (43%) had an event and 120 patients (13%) had died; 155 patients (17%) failed to achieve EFS12. From diagnosis, patients with FL had inferior OS compared to the general population (SMR=1.24, 95% CI: 1.03-1.48, p=0.018); results were similar for patients with grade 1-2 (SMR=1.23) and grade 3a (SMR=1.29) disease. The survival deficit was eliminated in patients who achieved EFS12 (SMR=0.85, 95% CI: 0.66-1.09, p=0.20, Fig 1a), and so we did not pursue modeling EFS24. In contrast, patients with a non-death event (relapse, retreatment, or progression) within 12 months of diagnosis had inferior subsequent OS (SMR=3.90, 95% CI: 2.89-5.25, p=4.8x10-19, Fig 1b). These results were replicated in 153 FL patients from the Lyon registry: patients who achieved EFS12 had equivalent subsequent OS to the general French population (SMR=0.82, 95% CI: 0.39-1.72, p=0.60, Fig 1c), while patients who failed to achieve EFS12 had poor subsequent OS (SMR=4.16, 95% CI: 1.34-12.91, p=0.013, Fig 1d). In subset analysis of the MER, patients achieving EFS12 initially treated with IC (SMR=0.98, 95% CI: 0.63-1.54, p=0.93), RM (SMR=0.66, 95% CI: 0.31-1.38, p=0.27), or observation (SMR=0.73, 95% CI: 0.47-1.15, p=0.18) had equivalent OS to the population. In contrast, for patients not achieving EFS12, OS after event was inferior for those treated with IC (SMR=15.0, 95% CI: 10.22-22.05, p=2.0x10-43) or RM (SMR=4.96, 95% CI: 1.24-19.84, p=0.023), while trending towards inferior for those initially observed (SMR=1.55, 95% CI: 0.81-2.99, p=0.19). Summary: Events within the first 12 months of diagnosis are associated with poor OS in FL, especially in patients treated with IC, while patients achieving EFS12 have excellent subsequent survival, overall and in the main treatment subsets. Prognosis for FL patients should be recalibrated at 12 months from diagnosis. EFS12 will be useful in counseling and should be considered as an endpoint in studies of newly diagnosed FL. Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

Abstract Abstract 3637 Background: A recent large genome-wide association study confirmed the important role of the major histocompatibility complex in classical Hodgkin Lymphoma (cHL) susceptibility (rs6903608), but also identified significant associations with genetic variants outside of the HLA region at chromosomal regions 2p16.1 (REL, rs1432295), 8q24.21 (PVT1, rs2608053, rs2019960), and 10p14 (GATA3, rs501764, rs485411). These single nucleotide polymorphisms (SNPs) are localized in or near important genes involved in lymphoma pathogenesis: REL, which encodes for c-rel, is a member of NFkB pathway; PVT1, which is downstream of the MYC locus, encodes for non-coding microRNAs, some of which have oncogenic properties; and GATA3, which is a critical transcriptional factor for priming lymphoid T-cells for Th2 phenotype, is aberrantly expressed in HL. We investigated whether these six SNPs described in cHL etiology also influence the outcome of newly diagnosed cHL patients in two independent cohorts. Patients and Methods: The first cohort consisted of 342 cHL patients from the Groupe d'Etude des Lymphomes de l'Adulte (GELA) who were prospectively enrolled between 1998 and 2002. The second cohort consisted of 259 patients prospectively enrolled in the University of Iowa/Mayo Clinic SPORE Molecular Epidemiology Resource (MER). DNA for genotyping was extracted from a blood samples collected at diagnosis, and genotyping was conducted using Taqman technology (ABI Prism 7000, Applied Biosystems) for HLA-DRA, PVT1, GATA3 and PCR-based restriction fragment length polymorphism for REL in GELA cohort and Illumina iSelect for the 6 SNPs in MER cohort. Both cohorts were followed for disease progression, re-treatment and death. In the GELA series, the median age was 32 years (range, 15–93), 57% were male, and 72% had an Ann Arbor stage I–II. Histology was nodular sclerosis in 84%, and 29% of available cases (n=40/140) were EBV positive. In the MER series, the median age was 38 years (range, 18–89), 53% were male, and 53% had an Ann Arbor stage I-II. Nodular sclerosis was the most common subtype (62%) and 23 of 115 available cases were EBV positive (20%). The International Prognostic Score (IPS) was 0–1 in 46% and 52% of GELA and MER patients, respectively. ABVD regimen was used for 60% and 88% of the GELA and MER patients, respectively. The 5-year progression free survival (PFS) was 83% and 75% in GELA and MER cohorts, respectively. We estimated the prognostic value of each individual SNP for PFS for allelic and genotypic (dominant and recessive) modes of transmission in each series. In order to increase power, we then performed a meta-analysis of the two studies. Results: Consistent with prior reports, the minor allele frequencies for REL (rs1432295), HLA-DRA (rs6903608), PVT1 (rs2608053), PVT1 (rs2019960), GATA3 (rs501764) and GATA3 (rs485411) were 0.44, 0.50, 0.43, 0.29, 0.22, 0.28 in the GELA and 0.46, 0.41, 0.46, 0.27, 0.25, 0.31 in the MER series, respectively. In GELA, GATA3 (rs501767) was associated with PFS in the ordinal model (HR=1.66, 95%CI 1.11–2.49, P=.01), while there were suggestive associations for PVT1 (rs2608053) (HR=1.76, 95%CI 0.95–3.26, P=.07) and REL (rs1432295) (HR=0.63, 95%CI 0.37–1.06, P=.08) in the dominant model. In the MER, PVT1 (rs2608053) was associated with PFS in the ordinal model (HR=1.42, 95%CI 0.99–2.03, P=.06), while there was a suggestive association with HLA-DRA (rs6903608) in the dominant model (HR=0.64, 95%CI 0.39–1.05, P=.08) for whole cohort but also for EBV negative cHL (HR=0.41, 95%CI 0.17–0.99, P=.05). In a meta-analysis of the two studies, PVT1 (rs2608053) was significantly associated with PFS in the ordinal (HR=1.34, 95%CI 1.04–1.73, P=.02) and the dominant (HR=1.88, 95%CI 1.20–2.95, P=.006) models. Further adjustment for IPS had minimal impact on these associations (ordinal HR=1.30, 95%CI 1.00–1.70; dominant HR=1.78, 95%CI 1.13–2.83). Patients with PVT1(rs2608053) GG, GA, AA genotypes had a 5-year PFS rate of 83%, 74% and 73% in GELA and 86%, 70%, and 73% in the MER, respectively. Conclusions: The non-HLA cHL susceptibility locus PVT1 (rs2608053) was associated with PFS in two independent cohorts of cHL cases, and after adjustment for the IPS. While associations with GATA3 and REL were only observed in one of the studies, their evaluation in other studies is warranted. Functional studies of PVT1 in cHL pathogenesis should be pursued. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 3655 Background Primary central nervous system lymphoma (PCNSL) is an aggressive lymphoma with devastating prognosis. High-dose methotrexate (HD-MTX) in combination with HD-cytarabine builds the backbone of current treatments. Elderly patients constitute 45% of cases, exhibit poor outcome and frequent iatrogenic toxicity. However, research efforts to optimize therapy in this subgroup have been neglected. On this background, we conducted a systematic review (SR) and individual patient data meta-analysis (IPDMA) to provide comprehensive evidence-based management strategy for elderly patients with PCNSL. Patients and Methods SR: We searched MEDLINE and EMBASE without language restriction. Eligibility criteria were prospective/retrospective observational studies or randomized trials (RCT) (all N>=10) that exclusively focused on first-line therapy/outcomes in immunocompetent PCNSL patients ≥60 years. Eligible studies were evaluated for methodological quality and reporting of the following baseline characteristics: Age, performance status (PS), involvement of deep brain structures (IDB), serum LDH at baseline, cerebro-spinal fluid (CSF) protein concentration elevation, neurotoxicity (as reported), specific co-morbidity indices, and functional status. For the IPDMA, investigators of eligible studies were asked to provide individual patient data. Minimal eligibility criteria: Age at baseline, details about first-line therapy, and follow-up information. If no data were available, studies were included in the SR, but not in the IPDMA. To maximize statistical power and generalizability, published/unpublished data from other international collaborators were included. Impact of different first-line treatments on overall survival (OS) was investigated using time dependent mixed effects multivariable Cox regression models (age and PS as fixed effects, study/database as random effect). Results SR: We identified 13 eligible studies including 583 patients in total, median age 68–76, published from 1996–2011. Design of studies: prospective (3 multicenter [1 RCT]; 2 single center), retrospective (4 multicenter and single-center, respectively). Accrual of the RCT was recently finished, but publication is pending. From published studies, information about age and therapy was given throughout, for clinical performance in 77%, for LDH and CSF protein in 15%, and IDB in 38%. Functional status was reported in only one study. From the identified 13 studies, 261 individual patient data were available for our IPDMA and pooled with 408 patients from other databases; altogether 669 patients diagnosed from 1977–2011. Preliminary results IPDMA: 50% were male, median age 68 (60–70 [N=431], 70–80 [N=211], >80 [N=22]); median KPS was 60% (10–100%). Therapy regimens widely varied. Overall response to first-line treatment was 65% (45% CR, 19% PR). After a median follow-up of 23 months (1–171), 44% were still alive, with a 3-year OS of 32% [95%CI, 29–37%]. Grouping by time of diagnosis revealed improvement for patients diagnosed after 1997 (N=462) (P<0.001). In multivariate analysis, MTX-based poly-chemotherapy (CT) (N=474) was associated with improved OS (Hazard ratio [HR] 0.69, 95% CI 0.52–0.91) compared to non-MTX regimens (N=195); this was consistent among patients who received consolidating WBRT (HR 0.33, 95% CI 0.01–0.66) and those who did not (HR 0.46, 95% CI 0.23–0.89). In patients who received any MTX-based poly-CT, addition of CHOP-like components (N=90) was not associated with improved OS (HR 0.98, 95% 0.65–1.48). Although any WBRT showed an overall trend for superior OS, it was associated with a 4-fold risk increase for neurotoxicity (Odds Ratio 4.21, 95% CI 2.23–8.21). Further results of treatment patterns and explorative comparisons will be presented at the meeting. Conclusion This international meta-analysis revealed widely varying treatment approaches and demonstrates that prognosis for elderly PCNSL patients is still poor. However, improvement over the last decades was observed. MTX-based poly-CT was associated with better outcome compared to non-MTX containing approaches. The addition of CHOP-like regimens to HD-MTX did not improve outcome. WBRT was associated with better outcome, but also clearly increased risk of neurotoxicity. Prospective trials designed ad hoc for elderly PCNSL patients are promptly needed. Disclosures: No relevant conflicts of interest to declare.

Abstract We previously identified five single nucleotide polymorphisms (SNPs) at four susceptibility loci for diffuse large B-cell lymphoma (DLBCL) in individuals of European ancestry through a large genome-wide association study (GWAS). To further elucidate genetic susceptibility to DLBCL, we sought to validate two loci at 3q13.33 and 3p24.1 that were suggestive in the original GWAS with additional genotyping. In the meta-analysis (5662 cases and 9237 controls) of the four original GWAS discovery scans and three replication studies, the 3q13.33 locus (rs9831894; minor allele frequency [MAF] = 0.40) was associated with DLBCL risk [odds ratio (OR) = 0.83, P = 3.62 × 10−13]. rs9831894 is in linkage disequilibrium (LD) with additional variants that are part of a super-enhancer that physically interacts with promoters of CD86 and ILDR1. In the meta-analysis (5510 cases and 12 817 controls) of the four GWAS discovery scans and four replication studies, the 3p24.1 locus (rs6773363; MAF = 0.45) was also associated with DLBCL risk (OR = 1.20, P = 2.31 × 10−12). This SNP is 29 426-bp upstream of the nearest gene EOMES and in LD with additional SNPs that are part of a highly lineage-specific and tumor-acquired super-enhancer that shows long-range interaction with AZI2 promoter. These loci provide additional evidence for the role of immune function in the etiology of DLBCL, the most common lymphoma subtype.