Genetics and Pathogenesis of Diffuse Large B-Cell Lymphoma

BACKGROUND

Diffuse large B-cell lymphomas (DLBCLs) are phenotypically and genetically heterogeneous. Gene-expression profiling has identified subgroups of DLBCL (activated B-cell-like [ABC], germinal-center B-cell-like [GCB], and unclassified) according to cell of origin that are associated with a differential response to chemotherapy and targeted agents. We sought to extend these findings by identifying genetic subtypes of DLBCL based on shared genomic abnormalities and to uncover therapeutic vulnerabilities based on tumor genetics.

METHODS

We studied 574 DLBCL biopsy samples using exome and transcriptome sequencing, array-based DNA copy-number analysis, and targeted amplicon resequencing of 372 genes to identify genes with recurrent aberrations. We developed and implemented an algorithm to discover genetic subtypes based on the co-occurrence of genetic alterations.

RESULTS

We identified four prominent genetic subtypes in DLBCL, termed MCD (based on the co-occurrence of MYD88L265P and CD79B mutations), BN2 (based on BCL6 fusions and NOTCH2 mutations), N1 (based on NOTCH1 mutations), and EZB (based on EZH2 mutations and BCL2 translocations). Genetic aberrations in multiple genes distinguished each genetic subtype from other DLBCLs. These subtypes differed phenotypically, as judged by differences in gene-expression signatures and responses to immunochemotherapy, with favorable survival in the BN2 and EZB subtypes and inferior outcomes in the MCD and N1 subtypes. Analysis of genetic pathways suggested that MCD and BN2 DLBCLs rely on "chronic active" B-cell receptor signaling that is amenable to therapeutic inhibition.

CONCLUSIONS

We uncovered genetic subtypes of DLBCL with distinct genotypic, epigenetic, and clinical characteristics, providing a potential nosology for precision-medicine strategies in DLBCL. (Funded by the Intramural Research Program of the National Institutes of Health and others.).

Treatment strategies, outcomes and prognostic factors in 291 patients with secondary CNS involvement by diffuse large B-cell lymphoma

PURPOSE

Secondary CNS involvement (SCNS) is a profoundly adverse complication of diffuse large B-cell lymphoma. Evidence from older series indicated a median overall survival (OS) < 6 months; however, data from the immunochemotherapy era are limited.

METHODS

Patients diagnosed with SCNS during or after first-line immunochemotherapy were identified from databases and/or regional/national registries from three continents. Clinical information was retrospectively collected from medical records.

RESULTS

In total, 291 patients with SCNS were included. SCNS occurred as part of first relapse in 254 (87%) patients and 113 (39%) had concurrent systemic relapse. With a median post-SCNS follow-up of 48 months, the median post-SCNS OS was 3.9 months and 2-year OS rate was 20% (95% CI: 15-25). In multivariable analysis of 173 patients treated with curative/intensive therapy (such as high-dose methotrexate [HDMTX] or platinum-containing regimens), age ≤60 years, performance status 0-1, absence of combined leptomeningeal and parenchymal involvement, and SCNS occurring after completion of first-line therapy were associated with superior outcomes. Patients ≤60 years with performance status 0-1 and treated with HDMTX-based regimens for isolated parenchymal SCNS had a 2-year OS of 62% (95% CI: 36-80). In patients with isolated SCNS, the addition of rituximab to HDMTX-based regimens was associated with improved OS. Amongst patients with isolated SCNS in CR following intensive treatment, high-dose chemotherapy and autologous stem cell transplantation did not improve OS (P = 0.9).

CONCLUSIONS

In this large international cohort of patients treated with first-line immunochemotherapy, outcomes following SCNS remain poor. However, a moderate proportion of patients with isolated SCNS who received intensive therapies achieved durable remissions.

Assessment of Capture and Amplicon-Based Approaches for the Development of a Targeted Next-Generation Sequencing Pipeline to Personalize Lymphoma Management

Targeted next-generation sequencing panels are increasingly used to assess the value of gene mutations for clinical diagnostic purposes. For assay development, amplicon-based methods have been preferentially used on the basis of short preparation time and small DNA input amounts. However, capture sequencing has emerged as an alternative approach because of high testing accuracy. We compared capture hybridization and amplicon sequencing approaches using fresh-frozen and formalin-fixed, paraffin-embedded tumor samples from eight lymphoma patients. Next, we developed a targeted sequencing pipeline using a 32-gene panel for accurate detection of actionable mutations in formalin-fixed, paraffin-embedded tumor samples of the most common lymphocytic malignancies: chronic lymphocytic leukemia, diffuse large B-cell lymphoma, and follicular lymphoma. We show that hybrid capture is superior to amplicon sequencing by providing deep more uniform coverage and yielding higher sensitivity for variant calling. Sanger sequencing of 588 variants identified specificity limits of thresholds for mutation calling, and orthogonal validation on 66 cases indicated 93% concordance with whole-genome sequencing. The developed pipeline and assay identified at least one actionable mutation in 91% of tumors from 219 lymphoma patients and revealed subtype-specific mutation patterns and frequencies consistent with the literature. This pipeline is an accurate and sensitive method for identifying actionable gene mutations in routinely acquired biopsy materials, suggesting further assessment of capture-based assays in the context of personalized lymphoma management.

Brentuximab Vedotin with Chemotherapy for Stage III or IV Hodgkin's Lymphoma

BACKGROUND

Brentuximab vedotin is an anti-CD30 antibody-drug conjugate that has been approved for relapsed and refractory Hodgkin's lymphoma.

METHODS

We conducted an open-label, multicenter, randomized phase 3 trial involving patients with previously untreated stage III or IV classic Hodgkin's lymphoma, in which 664 were assigned to receive brentuximab vedotin, doxorubicin, vinblastine, and dacarbazine (A+AVD) and 670 were assigned to receive doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD). The primary end point was modified progression-free survival (the time to progression, death, or noncomplete response and use of subsequent anticancer therapy) as adjudicated by an independent review committee. The key secondary end point was overall survival.

RESULTS

At a median follow-up of 24.6 months, 2-year modified progression-free survival rates in the A+AVD and ABVD groups were 82.1% (95% confidence interval [CI], 78.8 to 85.0) and 77.2% (95% CI, 73.7 to 80.4), respectively, a difference of 4.9 percentage points (hazard ratio for an event of progression, death, or modified progression, 0.77; 95% CI, 0.60 to 0.98; P=0.04). There were 28 deaths with A+AVD and 39 with ABVD (hazard ratio for interim overall survival, 0.73 [95% CI, 0.45 to 1.18]; P=0.20) [corrected]. All secondary efficacy end points trended in favor of A+AVD. Neutropenia occurred in 58% of the patients receiving A+AVD and in 45% of those receiving ABVD; in the A+AVD group, the rate of febrile neutropenia was lower among the 83 patients who received primary prophylaxis with granulocyte colony-stimulating factor than among those who did not (11% vs. 21%). Peripheral neuropathy occurred in 67% of patients in the A+AVD group and in 43% of patients in the ABVD group; 67% of patients in the A+AVD group who had peripheral neuropathy had resolution or improvement at the last follow-up visit. Pulmonary toxicity of grade 3 or higher was reported in less than 1% of patients receiving A+AVD and in 3% of those receiving ABVD. Among the deaths that occurred during treatment, 7 of 9 in the A+AVD group were associated with neutropenia and 11 of 13 in the ABVD group were associated with pulmonary-related toxicity.

CONCLUSIONS

A+AVD had superior efficacy to ABVD in the treatment of patients with advanced-stage Hodgkin's lymphoma, with a 4.9 percentage-point lower combined risk of progression, death, or noncomplete response and use of subsequent anticancer therapy at 2 years. (Funded by Millennium Pharmaceuticals and Seattle Genetics; ECHELON-1 ClinicalTrials.gov number, NCT01712490 ; EudraCT number, 2011-005450-60 .).

Outcomes in adolescents and young adults with Hodgkin lymphoma treated on US cooperative group protocols: An adult intergroup (E2496) and Children's Oncology Group (COG AHOD0031) comparative analysis

BACKGROUND

There is no clear consensus between pediatric and adult providers about the treatment of adolescents and young adults (AYAs) with Hodgkin lymphoma (HL).

METHODS

Failure-free survival (FFS) and overall survival (OS) were compared between 114 patients ages 17 to 21 years with HL who were treated on the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network Intergroup adult E2496 study and 391 similarly patients ages 17 to 21 years with HL who were treated on the pediatric Children's Oncology Group (COG) AHOD0031 study.

RESULTS

Comparing AYAs from the COG and E2496 studies, there were no significant differences in extralymphatic disease, anemia, or hypoalbuminemia. More AYAs in the E2496 trial had stage III and IV disease (63% vs 29%; P < .001) and B symptoms (63% vs 27%; P < .001), and fewer had bulk disease (33% vs 77%; P < .001). More AYAs on the COG trial received radiotherapy (76% vs 66%; P = .03), although in smaller doses. E2496 AYA The 5-year FFS and OS rates were 68% and 89%, respectively in the E2496 AYAs and 81% and 97%, respectively, in the COG AYAs, indicating a statistically superior compared in the COG AYAs (P = .001). In stratified multivariable analyses, E2496 AYAs had worse FFS than COG AYAs in all strata except patients who had stage I and II HL without anemia. Propensity score analysis (based on stage, anemia, and bulk disease) confirmed inferior FFS for E2496 AYAs compared with COG AYAs (P = .004). On the E2496 study, FFS was significantly divergent across age groups (P = .005), with inferior outcomes for those ages 17 to 21 years versus 22-44 years. There was no difference across age on the COG study.

CONCLUSIONS

Younger AYA patients with HL appear to have better outcomes when treated on a pediatric trial than patients of similar age on an adult trial. Prospective studies examining these differences are warranted. Cancer 2018;124:136-44. © 2017 American Cancer Society.

Brentuximab vedotin plus bendamustine in relapsed or refractory Hodgkin's lymphoma: an international, multicentre, single-arm, phase 1-2 trial

Background:

The major objective of this study was to explore the safety and clinical activity of Brentuximab vedotin (Bv) and bendamustine in combination in patients with relapsed or refractory Hodgkin Lymphoma. Bv produces high response rates and durable progression-free survival (PFS) in CD30-expressing lymphomas and is approved for the treatment of relapsed Hodgkin lymphoma (HL) and relapsed ALCL. Bendamustine (B) is active agent across the lymphoproliferative malignancies, though the PFS among patients with HL and PTCL is modest.

Methods:

This was an international, multicenter, single-arm, Phase 1–2 study of BvB in patients with relapsed or refractory HL and ALCL. Eligible patients were required to have relapsed/refractory CD30+ biopsy proven HL or ALCL and an ECOG Performance Status ≤2. In the Phase 1, HL patients were deemed eligible if they developed progressive disease following or after declining ASCT, or had at least 2 prior multi-agent chemotherapy regimens. In the Phase 2, patients with HL were eligible if they had relapsed or refractory disease after one line of therapy. Eligible ALCL patients were required to have relapsed after at least one prior multi-agent chemotherapy regimen and if they were not eligible for or have declined ASCT. The primary objective of the Phase I portion of this study was to identify the maximum tolerated dose (MTD) and dose limiting toxicity (DLT). The primary endpoint of the Phase 2 portion was to determine the overall response rate (ORR; complete response [CR] plus partial response [PR])) based on an intention to treat analysis (ITT). Secondary objectives of Phase 1–2 included assessing for duration of response, progression free survival and overall survival. Response was evaluated using International Harmonization Project Group 2007 Revised Response Criteria. Bv was escalated from 1.2mg/kg Day 1, and B from 70mg/m2 Days 1 and 2 every 21 days until the MTD or recommended phase 2 dose (RP2D) was reached. The study is ongoing but no longer recruiting patients. This trial is registered with ClinicalTrials.gov number NCT01657331.

Findings:

65 patients (only 1 ALCL) were treated, 28 on the Phase 1 and 37 on the phase 2. While the MTD of the combination was not reached, the single agent MTD of Bv (1.8mg/kg Day 1) and RP2D of B (90mg/m2 Days 1 and 2) were identified as the RP2D of the combination. Patients were heavily treated, 65% (42 of 65) had an autologous or allogeneic stem cell transplant or both. The Phase 1 revealed modest toxicity. The major Grade 3/4 toxicities included Grade 3 lung infection in 5 (14%) patients in the Phase 2, and Grade 3/4 neutropenia in 13 (24%) patients across the Phase 1 and 2. The Phase 1 and 2 overall response rates (ORR) were 61% and 78% respectively, with 43% (16 of 27) patients treated in the Phase 2 attaining a complete remission (CR). In the Phase 2, the median PFS has not been reached and duration of response (DOR) was 3.4 months. There was a total of 23 deaths with 21 due to progression of disease, 2 occurring after being transplanted, and none of which were treatment related.

Interpretation:

This demonstrates that BvB might be an effective salvage regimen for patients with HL, with a favorable safety profile.

Funding:

Seattle Genetics, The Lymphoma Research Fund of Columbia University and National Center for Advancing Translational Sciences, National Institutes of Health, through Grant Number UL1TR001873 provided support for this investigator initiated sponsored trial. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

International Assessment of Event-Free Survival at 24 Months and Subsequent Survival in Peripheral T-Cell Lymphoma

Purpose Peripheral T-cell lymphomas (PTCLs) have aggressive clinical behavior. We have previously shown that event-free survival (EFS) at 24 months (EFS24) is a clinically useful end point in diffuse large B-cell lymphoma. Here, we assess EFS24 and subsequent overall survival (OS) in large, multinational PTCL cohorts. Patients and Methods Patients with systemic PTCL newly diagnosed from 2000 to 2012 and treated with curative intent were included from the United States and Sweden (initial cohorts) and from Canada (replication cohort). EFS was defined as time from date of diagnosis to progression after primary treatment, retreatment, or death. Subsequent OS was measured after achieving EFS24 or from the time of progression if it occurred within 24 months. OS rates were compared with the age-, sex-, and country-matched general population. Results Seven hundred seventy-five patients were included in the study (the median age at diagnosis was 64 years; 63% were men). Results were similar in the initial and replication cohorts, and a combined analysis was undertaken. Sixty-four percent of patients progressed within the first 24 months and had a median OS of only 4.9 months (5-year OS, 11%). In contrast, median OS after achieving EFS24 was not reached (5-year OS, 78%), although relapses within 5 years of achieving EFS24 occurred in 23% of patients. Superior outcomes after achieving EFS24 were observed in younger patients (≤ 60 years of age: 5-year OS, 91%). Conclusion EFS24 stratifies subsequent outcome in PTCL. Patients with PTCL with primary refractory disease or early relapse have extremely poor survival. However, more than one third of patients with PTCL remain in remission 2 years after diagnosis with encouraging subsequent OS, especially in younger patients. These marked differences in outcome suggest that EFS24 has utility for patient counseling, study design, and risk stratification in PTCL.

Improved survival outcomes with the addition of rituximab to initial therapy for chronic lymphocytic leukemia: a comparative effectiveness analysis in the province of British Columbia, Canada

Chemoimmunotherapy with rituximab improves survival in clinical trials in upfront chronic lymphocytic leukemia (CLL) treatment. This study compared clinical outcomes with and without rituximab added to first-line chemotherapy in a provincial cohort of CLL patients. Between 1973 and 2014, 1345 patients received CLL treatment: 48% with rituximab, 52% chemotherapy alone. Median overall survival (OS) and treatment-free survival (TFS) were significantly longer with rituximab: OS 8.9 vs. 6.2 years, p < .0001; TFS 3.6 vs. 2.1 years, p < .0001. Addition of rituximab to chemotherapy was a strong independent predictor of mortality with a 32% mortality reduction after controlling for co-variates (age, sex, stage, and treatment with purine analogs). This large population-based study complements clinical trial and registry data demonstrating the benefit of adding rituximab to first-line CLL therapy and adds further evidence of the efficacy of rituximab-based chemoimmunotherapy in a real-world setting.

Treatment patterns and costs of care for patients with relapsed and refractory Hodgkin lymphoma treated with brentuximab vedotin in the United States: A retrospective cohort study

OBJECTIVES

Although brentuximab vedotin (BV) has changed the management of patients with relapsed or refractory Hodgkin lymphoma (RRHL), little information is available on routine clinical practice. We identified treatment patterns and costs of care among RRHL patients in the United States (US) treated with BV.

METHODS

A retrospective observational study of adults initiating BV for RRHL from 2011-2015, with ≥6 months of data prior to and following BV initiation, was conducted. Treatments were classified based on dispensations and chemotherapy administration. Median total and monthly costs were estimated based on all-cause healthcare resource use in 2015 US dollars (USD).

RESULTS

The cohort comprised 289 patients (59% male; mean age at diagnosis, 42 years) with a mean follow-up of 250 weeks. Eleven percent had BV salvage therapy prior to ASCT, and 32% had BV for a relapse post-ASCT. 43% received treatment post-BV, most commonly allogeneic stem cell transplant (SCT) and bendamustine (both 10.2%). Median (IQR) total costs from BV initiation to censoring were 294,790 (142,110-483,360) USD; and were highest among those treated with BV prior to ASCT (up to 421,900 [300,940-778,970] USD). Median monthly costs were almost 20,000 USD per month, and up to 25,000 USD per month among those with BV and ASCT. Medications were the greatest driver of median monthly costs.

CONCLUSIONS

Median total all-cause costs were almost 300,000 USD, and median monthly costs approximately 20,000 USD, per patient treated. Patients requiring treatment following BV continue to incur high costs, highlighting the economic burden associated with managing patients in the RRHL setting.

Prognostic Model to Predict Post-Autologous Stem-Cell Transplantation Outcomes in Classical Hodgkin Lymphoma

Purpose Our aim was to capture the biology of classical Hodgkin lymphoma (cHL) at the time of relapse and discover novel and robust biomarkers that predict outcomes after autologous stem-cell transplantation (ASCT). Materials and Methods We performed digital gene expression profiling on a cohort of 245 formalin-fixed, paraffin-embedded tumor specimens from 174 patients with cHL, including 71 with biopsies taken at both primary diagnosis and relapse, to investigate temporal gene expression differences and associations with post-ASCT outcomes. Relapse biopsies from a training cohort of 65 patients were used to build a gene expression-based prognostic model of post-ASCT outcomes (RHL30), and two independent cohorts were used for validation. Results Gene expression profiling revealed that 24% of patients exhibited poorly correlated expression patterns between their biopsies taken at initial diagnosis and relapse, indicating biologic divergence. Comparative analysis of the prognostic power of gene expression measurements in primary versus relapse specimens demonstrated that the biology captured at the time of relapse contained superior properties for post-ASCT outcome prediction. We developed RHL30, using relapse specimens, which identified a subset of high-risk patients with inferior post-ASCT outcomes in two independent external validation cohorts. The prognostic power of RHL30 was independent of reported clinical prognostic markers (both at initial diagnosis and at relapse) and microenvironmental components as assessed by immunohistochemistry. Conclusion We have developed and validated a novel clinically applicable prognostic assay that at the time of first relapse identifies patients with unfavorable post-ASCT outcomes. Moving forward, it will be critical to evaluate the clinical use of RHL30 in the context of positron emission tomography-guided response assessment and the evolving cHL treatment landscape.

ABVD chemotherapy with reduced radiation therapy rates in children, adolescents and young adults with all stages of Hodgkin lymphoma

Background

We adopted ABVD chemotherapy with risk-adapted radiation therapy (RT) as first-line therapy for children, adolescents and young adults with Hodgkin lymphoma (HL) in British Columbia in 2004.

Patients and methods

Patients ≤ 25 years diagnosed from 2004 to 2013 with all stages of HL who received ABVD as initial therapy were included.

Results

Among 55 children (age < 18 year) and 154 young adults (18-25 year), there were no significant differences among age groups for sex, histologic subtype, tumour bulk, B symptoms, prognostic risk groups or treatment received. The rates of complete response, partial response and progressive disease were 84%, 7% and 10% for children and 95%, 4% and 1% for young adults (P=0.01), respectively. Treatment failures in children all occurred within one year of completion, while 8/21 (38%) relapses in young adults occurred later (P=0.04). With a median follow-up of 66 months the 5-year progression-free (PFS) and overall survival (OS) were 85 ± 3% and 97 ± 1%, respectively. For limited stage disease, PFS was 90 ± 7% for children and 93 ± 3% for young adults (P=0.65); OS was 100% for both. For advanced stage patients, PFS and OS were also similar for the children and young adults (77 ± 7% versus 81 ± 4%; P=0.38 and OS 90 ± 6% versus 97 ± 2%; P=0.17). The rate of consolidative RT was low (21%) and did not differ between age groups.

Conclusion

ABVD is an effective treatment in children, adolescents and young adults with HL. Children were less likely to achieve complete response and demonstrated earlier relapses compared to young adults. RT may be omitted for the majority of patients while maintaining excellent 5-year OS.

Mapping the human T cell repertoire to recurrent driver mutations in MYD88 and EZH2 in lymphoma

Oncogenic "driver" mutations are theoretically attractive targets for the immunotherapy of lymphoid cancers, yet the proportion that can be recognized by T cells remains poorly defined. To address this issue without any confounding effects of the patient's immune system, we assessed T cells from 19 healthy donors for recognition of three common driver mutations in lymphoma: MYD88^L265P, EZH2^Y641F , and EZH2^Y641N . Donors collectively expressed the 10 most prevalent HLA class I alleles, including HLA-A*02:01. Peripheral blood T cells were primed with peptide-loaded dendritic cells (DC), and reactive T cells were assessed for recognition of naturally processed mutant versus wild type full-length proteins. After screening three driver mutations across 17-26 HLA class I alleles and 3 × 10⁶-3 × 10⁷ T cells per donor, we identified CD4⁺ T cells against EFISENCGEII from EZH2^Y641N (presented by HLA-DRB1*13:02) and CD8⁺ T cells against RPIPIKYKA from MYD88^L265P (presented by HLA-B*07:02). We failed to detect RPIPIKYKA-specific T cells in seven other HLA-B*07:02-positive donors, including two lymphoma patients. Thus, healthy donors harbor T cells specific for common driver mutations in lymphoma. However, such responses appear to be rare due to the combined limitations of antigen processing, HLA restriction, and T cell repertoire size, highlighting the need for highly individualized approaches for selecting targets.

The number of extranodal sites assessed by PET/CT scan is a powerful predictor of CNS relapse for patients with diffuse large B-cell lymphoma: An international multicenter study of 1532 patients treated with chemoimmunotherapy

PURPOSE

Development of secondary central nervous system involvement (SCNS) in patients with diffuse large B-cell lymphoma is associated with poor outcomes. The CNS International Prognostic Index (CNS-IPI) has been proposed for identifying patients at greatest risk, but the optimal model is unknown.

METHODS

We retrospectively analysed patients with diffuse large B-cell lymphoma diagnosed between 2001 and 2013, staged with PET/CT and treated with R-CHOP(-like) regimens. Baseline clinicopathologic characteristics, treatments, and outcome data were collected from clinical databases and medical files. We evaluated the association between candidate prognostic factors and modelled different risk models for predicting SCNS.

RESULTS

Of 1532 patients, 62 (4%) subsequently developed SCNS. By multivariate analysis, disease stage III/IV, elevated serum LDH, kidney/adrenal and uterine/testicular involvement were independently associated with SCNS. There was a strong correlation between absolute number of extranodal sites and risk of SCNS; the 144 patients (9%) with >2 extranodal sites had a 3-year cumulative incidence of SCNS of 15.2% (95% confidence interval [CI] 9.2-21.2%) compared with 2.6% (95% CI 1.7-3.5) among those with ≤2 sites (P < 0.001). The 3-year cumulative risks of SCNS for CNS-IPI defined risk groups were 11.2%, 3.1% and 0.4% for high-, intermediate- and low-risk patients, respectively. All risk models analysed had high negative predictive values, but only modest positive predictive values.

CONCLUSIONS

Patients with >2 extranodal sites or high-risk disease according to the CNS-IPI should be considered for baseline CNS staging. Clinical risk prediction models suffer from limited positive predictive ability, highlighting the need for more sensitive biomarkers to identify patients at highest risk of this devastating complication.

New Molecular Assay for the Proliferation Signature in Mantle Cell Lymphoma Applicable to Formalin-Fixed Paraffin-Embedded Biopsies

Purpose Mantle cell lymphoma is an aggressive B-cell neoplasm that displays heterogeneous outcomes after treatment. In 2003, the Lymphoma/Leukemia Molecular Profiling Project described a powerful biomarker-the proliferation signature-using gene expression in fresh frozen material. Herein, we describe the training and validation of a new assay that measures the proliferation signature in RNA derived from routinely available formalin-fixed paraffin-embedded (FFPE) biopsies. Methods Forty-seven FFPE biopsies were used to train an assay on the NanoString platform, using microarray gene expression data of matched fresh frozen biopsies as a gold standard. The locked assay was applied to pretreatment FFPE lymph node biopsies from an independent cohort of 110 patients uniformly treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone. Seventeen biopsies were tested across three laboratories to assess assay reproducibility. Results The MCL35 assay, which contained a 17-gene proliferation signature, yielded gene expression of sufficient quality to assign an assay score and risk group in 108 (98%) of 110 archival FFPE biopsies. The MCL35 assay assigned patients to high-risk (26%), standard-risk (29%), and low-risk (45%) groups, with different lengths of overall survival (OS): a median of 1.1, 2.6, and 8.6 years, respectively (log-rank for trend, P < .001). In multivariable analysis, these risk groups and the Mantle Cell Lymphoma International Prognostic Index were independently associated with OS ( P < .001 for both variables). Concordance of risk assignment across the three independent laboratories was 100%. Conclusion The newly developed and validated MCL35 assay for FFPE biopsies uses the proliferation signature to define groups of patients with significantly different OS independent of the Mantle Cell Lymphoma International Prognostic Index. Importantly, the analytic and clinical validity of this assay defines it as a reliable biomarker to support risk-adapted clinical trials.

Nonrandom occurrence of lymphoid cancer types in 140 families

We studied 140 families with two or more lymphoid cancers, including non-Hodgkin lymphoma (NHL), Hodgkin lymphoma (HL), chronic lymphocytic leukemia (CLL), and multiple myeloma (MM), for deviation from the population age of onset and lymphoid cancer co-occurrence patterns. Median familial NHL, HL, CLL and MM ages of onset are substantially earlier than comparable population data. NHL, HL and CLL (but not MM) also show earlier age of onset in later generations, known as anticipation. The co-occurrence of lymphoid cancers is significantly different from that expected based on population frequencies (p < .0001), and the pattern differs more in families with more affected members (p < .0001), suggesting specific lymphoid cancer combinations have a shared genetic basis. These families provide evidence for inherited factors that increase the risk of multiple lymphoid cancers. This study was approved by the BC Cancer Agency - University of British Columbia Clinical Research Ethics Board.

Combined copy number and mutation analysis identifies oncogenic pathways associated with transformation of follicular lymphoma

Follicular lymphoma (FL) is typically an indolent disease, but 30-40% of FL cases transform into an aggressive lymphoma (tFL) with a poor prognosis. To identify the genetic changes that drive this transformation, we sequenced the exomes of 12 cases with paired FL and tFL biopsies and identified 45 recurrently mutated genes in the FL-tFL data set and 39 in the tFL cases. We selected 496 genes of potential importance in transformation and sequenced them in 23 additional tFL cases. Integration of the mutation data with copy-number abnormality (CNA) data provided complementary information. We found recurrent mutations of miR-142, which has not been previously been reported to be mutated in FL/tFL. The genes most frequently mutated in tFL included KMT2D (MLL2), CREBBP, EZH2, BCL2 and MEF2B. Many recurrently mutated genes are involved in epigenetic regulation, the Janus-activated kinase-signal transducer and activator of transcription (STAT) or the nuclear factor-κB pathways, immune surveillance and cell cycle regulation or are TFs involved in B-cell development. Of particular interest are mutations and CNAs affecting S1P-activated pathways through S1PR1 or S1PR2, which likely regulate lymphoma cell migration and survival outside of follicles. Our custom gene enrichment panel provides high depth of coverage for the study of clonal evolution or divergence.

Hodgkin Lymphoma: Current Status and Clinical Trial Recommendations

The National Clinical Trials Network lymphoid malignancies Clinical Trials Planning Meeting (CTPM) occurred in November of 2014. The scope of the CTPM was to prioritize across the lymphoid tumors clinically significant questions and to foster strategies leading to biologically informed and potentially practice changing clinical trials. This review from the Hodgkin lymphoma (HL) subcommittee of the CTPM discusses the ongoing clinical challenges in HL, outlines the current standard of care for HL patients from early to advanced stage, and surveys the current science with respect to biomarkers and the landscape of ongoing clinical trials. Finally, we suggest areas of unmet need in HL and elucidate promising therapeutic strategies to guide future HL clinical trials planning across the NCTN.

A time-and-motion approach to micro-costing of high-throughput genomic assays

BACKGROUND

Genomic technologies are increasingly used to guide clinical decision-making in cancer control. Economic evidence about the cost-effectiveness of genomic technologies is limited, in part because of a lack of published comprehensive cost estimates. In the present micro-costing study, we used a time-and-motion approach to derive cost estimates for 3 genomic assays and processes-digital gene expression profiling (gep), fluorescence in situ hybridization (fish), and targeted capture sequencing, including bioinformatics analysis-in the context of lymphoma patient management.

METHODS

The setting for the study was the Department of Lymphoid Cancer Research laboratory at the BC Cancer Agency in Vancouver, British Columbia. Mean per-case hands-on time and resource measurements were determined from a series of direct observations of each assay. Per-case cost estimates were calculated using a bottom-up costing approach, with labour, capital and equipment, supplies and reagents, and overhead costs included.

RESULTS

The most labour-intensive assay was found to be fish at 258.2 minutes per case, followed by targeted capture sequencing (124.1 minutes per case) and digital gep (14.9 minutes per case). Based on a historical case throughput of 180 cases annually, the mean per-case cost (2014 Canadian dollars) was estimated to be $1,029.16 for targeted capture sequencing and bioinformatics analysis, $596.60 for fish, and $898.35 for digital gep with an 807-gene code set.

CONCLUSIONS

With the growing emphasis on personalized approaches to cancer management, the need for economic evaluations of high-throughput genomic assays is increasing. Through economic modelling and budget-impact analyses, the cost estimates presented here can be used to inform priority-setting decisions about the implementation of such assays in clinical practice.

Uterine, but not ovarian, female reproductive organ involvement at presentation by diffuse large B-cell lymphoma is associated with poor outcomes and a high frequency of secondary CNS involvement

Involvement of the internal female reproductive organs by diffuse large B-cell lymphoma (DLBCL) is uncommon, and there are sparse data describing the outcomes of such cases. In total, 678 female patients with DLBCL staged with positron emission tomography/computed tomography and treated with rituximab-containing chemotherapy were identified from databases in Denmark, Great Britain, Australia, and Canada. Overall, 27/678 (4%) had internal reproductive organ involvement: uterus (n = 14), ovaries (n = 10) or both (n = 3). In multivariate analysis, women with uterine DLBCL experienced inferior progression-free survival and overall survival compared to those without reproductive organ involvement, whereas ovarian DLBCL was not predictive of outcome. Secondary central nervous system (CNS) involvement (SCNS) occurred in 7/17 (41%) women with uterine DLBCL (two patients with concomitant ovarian DLBCL) and 0/10 women with ovarian DLBCL without concomitant uterine involvement. In multivariate analysis adjusted for other risk factors for SCNS, uterine involvement by DLBCL remained strongly associated with SCNS (Hazard ratio 14·13, 95% confidence interval 5·09-39·25, P < 0·001). Because involvement of the uterus by DLBCL appears to be associated with a high risk of SCNS, those patients should be considered for CNS staging and prophylaxis. However, more studies are needed to determine whether the increased risk of secondary CNS involvement also applies to women with localized reproductive organ DLBCL.

Clinical characteristics and outcomes of patients with Hodgkin lymphoma with central nervous system involvement: An international multicenter collaboration

Central nervous system (CNS) involvement is rare in patients with Hodgkin lymphoma (HL). Thus, the clinical features and outcomes are not well described. Cases of histologically confirmed CNS HL diagnosed between 1995 and 2015 were retrospectively identified in institutional (n = 7), national (n = 2), and cooperative group (n = 1) databases. We screened 30,781 patients with HL in our combined databases and identified 21 patients meeting eligibility criteria, an estimated frequency of 0.07%. CNS involvement was present at initial diagnosis in 10 patients (48%) and a feature of relapsed/refractory disease in 11 (52%). Among these 11 patients, the median time from initial diagnosis of HL to development of CNS involvement was 1.9 years (range 0.4-6.6) and the median number of prior lines of therapy was 2 (range 1-7). Altogether, treatments included radiation, multiagent systemic chemotherapy, combined modality therapy, and subtotal resection. The overall response rate was 65%. After a median follow-up of 3.6 years (range 0.8-13.2) from diagnosis of CNS HL, the median PFS and OS were 7.6 and 29 months, respectively. CNS involvement as a feature of relapsed/refractory disease was adversely prognostic for both PFS and OS; however, four patients remain alive and free of relapse at 7-78 months follow-up. CNS involvement in HL is exceedingly rare and has a distinct clinical presentation with predilection for parenchymal lesions with dural extension. Around one-quarter of patients, mostly with CNS involvement at initial HL diagnosis, experience prolonged disease-free survival. Am. J. Hematol. 91:894-899, 2016. © 2016 Wiley Periodicals, Inc.

Evaluation of the Risk of Relapse in Classical Hodgkin Lymphoma at Event-Free Survival Time Points and Survival Comparison With the General Population in British Columbia

Purpose

Studies in classical Hodgkin lymphoma (cHL) typically measure the time to events from diagnosis. We evaluated the risk of relapse at event-free survival time points in cHL and compared the risk of death to expected mortality rates in British Columbia (BC).

Methods

The BC Cancer Agency Lymphoid Cancer Database was screened to identify all patients age 16 to 69 years diagnosed with cHL between 1989 and 2012 treated with the chemotherapy regimen of doxorubicin, bleomycin, vinblastine, and dacarbazine (or equivalent). We compared the observed mortality to the general population using age-, sex-, and calendar period–generated expected mortality rates from BC life-tables. Relative survival was calculated using a conditional approach and expressed as a standardized mortality ratio of observed-to-expected deaths.

Results

One thousand four hundred two patients were identified; 749 patients were male (53%), the median age was 32 years, and 68% had advanced-stage disease. The median follow-up time was 8.4 years. Seventy-two percent of relapses occurred within the first 2 years of diagnosis. For all patients, the 5-year risk of relapse from diagnosis was 18.1% but diminished to 5.6% for patients remaining event free at 2 years. For advanced-stage patients who were event free at 2 years, the 5-year risk of relapse was only 7.6%, and for those who were event free at 3 years, it was comparable to that of limited-stage patients (4.1% v 2.5%, respectively; P = .07). Furthermore, international prognostic score ≥ 4 and bulky disease were no longer prognostic in patients who were event free at 1 year. Although the relative survival improved as patients remained in remission, it did not normalize compared with the general population.

Conclusion

Patients with cHL who are event free at 2 years have an excellent outcome regardless of baseline prognostic factors. All patients with cHL had an enduring increased risk of death compared with the general population.

CNS International Prognostic Index: A Risk Model for CNS Relapse in Patients With Diffuse Large B-Cell Lymphoma Treated With R-CHOP

PURPOSE

To develop and validate a risk score for relapse in the CNS in patients with diffuse large B-cell lymphoma (DLBCL).

PATIENTS AND METHODS

A total of 2,164 patients (18 to 80 years old) with aggressive B-cell lymphomas (80% DLBCL) treated with rituximab and CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone)-like chemotherapy, who were enrolled in studies from the German High-Grade Non-Hodgkin Lymphoma Study Group and the MabThera International Trial, were analyzed for occurrence of relapse/progression in the CNS. The resulting risk model was validated in an independent data set of 1,597 patients with DLBCL identified in the British Columbia Cancer Agency Lymphoid Cancer database.

RESULTS

The risk model consists of the International Prognostic Index (IPI) factors in addition to involvement of kidneys and/or adrenal glands (CNS-IPI). In a three-risk group model, the low-risk group (46% of all patients analyzed), the intermediate-risk group (41%), and the high-risk group (12%) showed 2-year rates of CNS disease of 0.6% (CI, 0% to 1.2%), 3.4% (CI, 2.2% to 4.4%), and 10.2% (CI, 6.3% to 14.1%), respectively. Patients from the validation British Columbia Cancer Agency data set showed similar rates of CNS disease for low-risk (0.8%; CI, 0.0% to 1.6%), intermediate-risk (3.9%; CI, 2.3% to 5.5%), and high-risk (12.0%; CI, 7.9% to 16.1%) groups.

CONCLUSION

The CNS-IPI is a robust, highly reproducible tool that can be used to estimate the risk of CNS relapse/progression in patients with DLBCL treated with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy. Close to 90% of patients with DLBCL belong to the low- and intermediate-risk groups and have a CNS relapse risk < 5%; they may be spared any diagnostic and therapeutic intervention. In contrast, those in the high-risk group have a > 10% risk of CNS relapse and should be considered for CNS-directed investigations and prophylactic interventions.

Surge-Like Luteinising Hormone Secretion Induced by Retrochiasmatic Area NK3R Activation is Mediated Primarily by Arcuate Kisspeptin Neurones in the Ewe

The neuropeptides neurokinin B (NKB) and kisspeptin are potent stimulators of gonadotrophin-releasing hormone (GnRH)/luteinsing hormone (LH) secretion and are essential for human fertility. We have recently demonstrated that selective activation of NKB receptors (NK3R) within the retrochiasmatic area (RCh) and the preoptic area (POA) triggers surge-like LH secretion in ovary-intact ewes, whereas blockade of RCh NK3R suppresses oestradiol-induced LH surges in ovariectomised ewes. Although these data suggest that NKB signalling within these regions of the hypothalamus mediates the positive-feedback effects of oestradiol on LH secretion, the pathway through which it stimulates GnRH/LH secretion remains unclear. We proposed that the action of NKB on RCh neurones drives the LH surge by stimulating kisspeptin-induced GnRH secretion. To test this hypothesis, we quantified the activation of the preoptic/hypothalamic populations of kisspeptin neurones in response to POA or RCh administration of senktide by dual-label immunohistochemical detection of kisspeptin and c-Fos (i.e. marker of neuronal activation). We then administered the NK3R agonist, senktide, into the RCh of ewes in the follicular phase of the oestrous cycle and conducted frequent blood sampling during intracerebroventricular infusion of the kisspeptin receptor antagonist Kp-271 or saline. Our results show that the surge-like secretion of LH induced by RCh senktide administration coincided with a dramatic increase in c-Fos expression within arcuate nucleus (ARC) kisspeptin neurones, and was completely blocked by Kp-271 infusion. We substantiate these data with evidence of direct projections of RCh neurones to ARC kisspeptin neurones. Thus, NKB-responsive neurones in the RCh act to stimulate GnRH secretion by inducing kisspeptin release from KNDy neurones.

Hodgkin lymphoma in the elderly, pregnant, and HIV-infected

Hodgkin lymphoma (HL) presenting in patients with co-incidental advanced age, pregnancy, or human immunodeficiency virus (HIV) infection is uniquely challenging to manage. In this article we integrate recent evidence and clinical expertise to present recommendations for diagnosis and therapeutic management. Older patients with HL need to be carefully evaluated for comorbidies after which judicious choice of chemotherapy should minimize functional compromise. A pregnant patient with concurrent HL should be staged with minimal use of imaging requiring ionizing radiation and treated in an individualized manner optimally combining the strategies of treatment deferral when appropriate, use of single-agent vinblastine for symptomatic disease and reservation of multi-agent chemotherapy for the small minority of patients with aggressive clinical presentation. Treatment of HL coincident with HIV infection requires a combination of highly active anti-retroviral agents (HAART), standard multi-agent chemotherapy with meticulous attention to drug-drug interactions, and vigorous supportive care to ensure the best chance of cure.

Response assessment in lymphoma: Concordance between independent central review and local evaluation in a clinical trial setting

BACKGROUND

Independent central review of clinical imaging remains the standard for oncology clinical trials with registration potential. A limited independent central review strategy has been proposed for solid tumor trials based on concordance between central and local evaluation of response. Concordance between independent central review and local evaluation of response in hematological malignancies is not known.

METHODS

We retrospectively evaluated concordance between prospectively performed central and local assessments of response using the Revised Response Criteria for Malignant Lymphoma across two international, open-label, single-arm, registration studies of brentuximab vedotin in patients with relapsed or refractory Hodgkin lymphoma (N = 102) or systemic anaplastic large-cell lymphoma (N = 58).

RESULTS

Overall objective response rates were similar between assessors for both the trial in Hodgkin lymphoma (75% independent central review, 72% local evaluation) and the trial in anaplastic large-cell lymphoma (86% independent central review, 83% local evaluation). Patient-specific objective response concordance was also substantial (Hodgkin lymphoma: kappa = 0.68; anaplastic large-cell lymphoma: kappa = 0.74). Median progression-free survival was similar between assessors for patients with anaplastic large-cell lymphoma (14.3 months by independent central review (95% confidence interval: 6.9, -); 14.5 months by local evaluation (95% confidence interval: 9.4, -)), but longer by local evaluation in patients with Hodgkin lymphoma (5.8 months by independent central review (95% confidence interval: 5.0, 9.0); 9.0 months by local evaluation (95% confidence interval: 7.1, 12.0)). Median duration of response was longer by local evaluation in both malignancies, which was primarily attributable to earlier computed tomography and positron emission tomography-based scoring of progression by independent central review.

CONCLUSION

A limited independent review audit strategy for clinical trials of some lymphomas appears feasible and practical based on substantial concordance in assessments of overall objective response by central and local evaluation in two international, prospective, registration trials in lymphoma. Some variability between assessors in the time-to-event endpoints was observed, which appeared attributable to earlier assignments of progression by independent central review compared with local evaluation.

The value of routine bone marrow biopsy in patients with diffuse large B-cell lymphoma staged with PET/CT: a Danish-Canadian study

BACKGROUND

The added diagnostic and prognostic value of routine bone marrow biopsy (BMB) in patients with diffuse large B-cell lymphoma (DLBCL) undergoing positron emission tomography combined with computed tomography (PET/CT) staging is controversial.

PATIENTS AND METHODS

Patients with newly diagnosed DLBCL who underwent both staging PET/CT and BMB were retrospectively identified in British Columbia, Aalborg, and Copenhagen. Original written PET/CT and pathology reports were retrospectively reviewed to determine Ann Arbor stage and outcomes, with and without the contribution of BMB.

RESULTS

A total of 530 patients were identified: 146 (28%) had focal bone marrow (BM) lesions on PET/CT and 87 (16%) had positive BMB. Fifty-two of 146 patients (36%) with positive PET/CT had a positive BMB [39 DLBCL, 13 indolent non-Hodgkin lymphoma (iNHL)], while 35 of 384 patients (9%) with negative PET/CT had positive BMB (12 DLBCL, 23 iNHL). BMB upstaged 12/209 (6%) of stage I/II patients to stage IV, although this was the case for only 3 (1%) patients with DLBCL in the BMB. PET/CT identified BM involvement by BMB with sensitivity 60%, specificity 79%, positive predictive value 36%, and negative predictive value 91%. Concordant histological involvement of the BM by DLBCL was associated with worse overall survival and progression-free survival than discordant or no involvement in univariate and multivariate analyses.

CONCLUSIONS

In patients with DLBCL, staging PET/CT can miss BM involvement with concordant DLBCL (less common) or discordant iNHL (more common). Routine BMB does not add relevant diagnostic or prognostic value over PET/CT alone in the majority of patients with DLBCL.

Meta-analysis of genome-wide association studies discovers multiple loci for chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a common lymphoid malignancy with strong heritability. To further understand the genetic susceptibility for CLL and identify common loci associated with risk, we conducted a meta-analysis of four genome-wide association studies (GWAS) composed of 3,100 cases and 7,667 controls with follow-up replication in 1,958 cases and 5,530 controls. Here we report three new loci at 3p24.1 (rs9880772, EOMES, P=2.55 × 10(-11)), 6p25.2 (rs73718779, SERPINB6, P=1.97 × 10(-8)) and 3q28 (rs9815073, LPP, P=3.62 × 10(-8)), as well as a new independent SNP at the known 2q13 locus (rs9308731, BCL2L11, P=1.00 × 10(-11)) in the combined analysis. We find suggestive evidence (P<5 × 10(-7)) for two additional new loci at 4q24 (rs10028805, BANK1, P=7.19 × 10(-8)) and 3p22.2 (rs1274963, CSRNP1, P=2.12 × 10(-7)). Pathway analyses of new and known CLL loci consistently show a strong role for apoptosis, providing further evidence for the importance of this biological pathway in CLL susceptibility.

Lifetime physical activity and the risk of non-Hodgkin lymphoma

Research regarding the association between physical activity and the risk of non-Hodgkin lymphoma (NHL) is limited and inconsistent, and few studies have investigated whether the intensity and timing of physical activity influence the association. A case-control study of NHL was conducted in British Columbia, Canada, in 2000 to 2004. Data were collected on various NHL risk factors, including moderate-intensity and vigorous-intensity physical activity performed over the lifetime. Logistic regression was used to estimate the association between physical activity and the risk of NHL. This analysis included 818 controls and 749 cases. Lifetime vigorous-intensity physical activity was inversely associated with NHL risk. Participants in the second, third, and fourth quartiles of lifetime vigorous-intensity physical activity had an approximately 25% to 30% lower risk of NHL than those in the lowest quartile [adjusted odds ratios, 0.69 (95% confidence interval [CI], 0.52-0.93); 0.68 (95% CI, 0.50-0.92); and 0.75 (95% CI, 0.55-1.01), respectively]. No consistent associations were observed for total or moderate-intensity physical activity. There were no apparent age periods in which physical activity appeared to confer a greater risk reduction. In this study, we found that lifetime vigorous-intensity physical activity was associated with a significantly reduced risk of NHL. Given this finding, more research on physical activity intensity and timing in relation to NHL risk is warranted.

Toward Personalized Lymphoma Immunotherapy: Identification of Common Driver Mutations Recognized by Patient CD8+ T Cells

PURPOSE

A fundamental challenge in the era of next-generation sequencing (NGS) is to design effective treatments tailored to the mutational profiles of tumors. Many newly discovered cancer mutations are difficult to target pharmacologically; however, T-cell-based therapies may provide a valuable alternative owing to the exquisite sensitivity and specificity of antigen recognition. To explore this concept, we assessed the immunogenicity of a panel of genes that are common sites of driver mutations in follicular lymphoma, an immunologically sensitive yet currently incurable disease.

EXPERIMENTAL DESIGN

Exon capture and NGS were used to interrogate tumor samples from 53 patients with follicular lymphoma for mutations in 10 frequently mutated genes. For 13 patients, predicted mutant peptides and proteins were evaluated for recognition by autologous peripheral blood T cells after in vitro priming.

RESULTS

Mutations were identified in 1-5 genes in 81% (43/53) of tumor samples. Autologous, mutation-specific CD8(+) T cells were identified in 23% (3/13) of evaluated cases. T-cell responses were directed toward putative driver mutations in CREBBP and MEF2B. Responding T cells showed exquisite specificity for mutant versus wild-type proteins and recognized lymphoma cells expressing the appropriate mutations. Responding T cells appeared to be from the naïve repertoire, as they were found at low frequencies and only at single time points in each patient.

CONCLUSIONS

Patients with follicular lymphoma harbor rare yet functionally competent CD8(+) T cells specific for recurrent mutations. Our results support the concept of using NGS to design individualized immunotherapies targeting common driver mutations in follicular lymphoma and other malignancies. Clin Cancer Res; 22(9); 2226-36. ©2015 AACR.

Analysis of Heritability and Shared Heritability Based on Genome-Wide Association Studies for Thirteen Cancer Types

BACKGROUND

Studies of related individuals have consistently demonstrated notable familial aggregation of cancer. We aim to estimate the heritability and genetic correlation attributable to the additive effects of common single-nucleotide polymorphisms (SNPs) for cancer at 13 anatomical sites.

METHODS

Between 2007 and 2014, the US National Cancer Institute has generated data from genome-wide association studies (GWAS) for 49 492 cancer case patients and 34 131 control patients. We apply novel mixed model methodology (GCTA) to this GWAS data to estimate the heritability of individual cancers, as well as the proportion of heritability attributable to cigarette smoking in smoking-related cancers, and the genetic correlation between pairs of cancers.

RESULTS

GWAS heritability was statistically significant at nearly all sites, with the estimates of array-based heritability, hl (2), on the liability threshold (LT) scale ranging from 0.05 to 0.38. Estimating the combined heritability of multiple smoking characteristics, we calculate that at least 24% (95% confidence interval [CI] = 14% to 37%) and 7% (95% CI = 4% to 11%) of the heritability for lung and bladder cancer, respectively, can be attributed to genetic determinants of smoking. Most pairs of cancers studied did not show evidence of strong genetic correlation. We found only four pairs of cancers with marginally statistically significant correlations, specifically kidney and testes (ρ = 0.73, SE = 0.28), diffuse large B-cell lymphoma (DLBCL) and pediatric osteosarcoma (ρ = 0.53, SE = 0.21), DLBCL and chronic lymphocytic leukemia (CLL) (ρ = 0.51, SE =0.18), and bladder and lung (ρ = 0.35, SE = 0.14). Correlation analysis also indicates that the genetic architecture of lung cancer differs between a smoking population of European ancestry and a nonsmoking Asian population, allowing for the possibility that the genetic etiology for the same disease can vary by population and environmental exposures.

CONCLUSION

Our results provide important insights into the genetic architecture of cancers and suggest new avenues for investigation.

Rituximab with high-dose methotrexate in primary central nervous system lymphoma

The addition of rituximab (R) to chemotherapy improves outcomes in patients with systemic B-cell non-Hodgkin lymphomas, but the impact in patients with primary central nervous system lymphoma (PCNSL) receiving high-dose methotrexate (HDMTX) is unknown. Patients diagnosed with PCNSL at the British Columbia Cancer Agency (BCCA) between 2000 and 2013 were treated with ≥1 cycle of HDMTX 8 g/m(2) every 2 weeks, to best response or 10 cycles. After 2006, rituximab 375 mg/m(2) was given every 2 weeks with HDMTX for a total of 4 doses. 49 (66%) patients received HDMTX alone and 25 (34%) HDMTX+R, with a median of 5 (range 1-10) HDMTX cycles, and no difference between groups. The median follow-up was 5 years: 8.8 years (range 3.15-13.5 years) HDMTX and 1.9 years (range 0.5-7 years) HDMTX+R. The 5-year PFS was 17%, with no difference between groups (HR: 0.75, 95% CI: 0.41-1.35; P = 0.33). The 5-year OS was 38%, with no difference between the groups OS (HR: 0.73, 95% CI: 0.35-1.52; P = 0.39). In this retrospective study comparing two subgroups of patients treated in different eras, the addition of R to HDMTX did not appear to improve outcomes in PCNSL, possibly consistent with its known poor CNS penetration. It is possible that with a larger sample size, longer follow-up, or different rituximab dosing/schedule, the addition of rituximab may lead to a statistically significant improvement in outcomes. Prospective randomized trials currently in progress will more definitively estimate the impact of the addition of rituximab to HDMTX-based chemotherapy for PCNSL.

Outcome prediction by extranodal involvement, IPI, R-IPI, and NCCN-IPI in the PET/CT and rituximab era: A Danish-Canadian study of 443 patients with diffuse-large B-cell lymphoma

18F-fluorodeoxyglucose PET/CT (PET/CT) is the current state-of-the-art in the staging of diffuse large B-cell lymphoma (DLBCL) and has a high sensitivity for extranodal involvement. Therefore, reassessment of extranodal involvement and the current prognostic indices in the PET/CT era is warranted. We screened patients with newly diagnosed DLBCL seen at the academic centers of Aalborg, Copenhagen, and British Columbia for eligibility. Patients that had been staged with PET/CT and treated with R-CHOP(-like) 1(st) line treatment were retrospectively included. In total 443 patients met the inclusion criteria. With a median follow-up of 2.4 years, the 3-year overall (OS) and progression-free survival (PFS) were 73% and 69%, respectively. The Ann Arbor classification had no prognostic impact in itself with the exception of stage IV disease (HR 2.14 for PFS, P<0.01). Extranodal involvement was associated with a worse outcome in general, and in particular for patients with involvement of >2 extranodal sites, including HR 7.81 (P < 0.001) for PFS for >3 sites. Bone/bone marrow involvement was the most commonly involved extranodal site identified by PET/CT (29%) and was associated with an inferior PFS and OS. The IPI, R-IPI, and NCCN-IPI were predictive of PFS and OS, and the two latter could identify a very good prognostic subgroup with 3-year PFS and OS of 100%. PET/CT-ascertained extranodal involvement in DLBCL is common and involvement of >2 extranodal sites is associated with a dismal outcome. The IPI, R-IPI, and NCCN-IPI predict outcome with high accuracy.