Report of consensus panel 7 from the 11th international workshop on Waldenström macroglobulinemia on priorities for novel clinical trials.

Recent advances in the understanding of Waldenström macroglobulinemia (WM) biology have impacted the development of effective novel agents and improved our knowledge of how the genomic background of WM may influence selection of therapy. Consensus Panel 7 (CP7) of the 11th International Workshop on WM was convened to examine the current generation of completed and ongoing clinical trials involving novel agents, consider updated data on WM genomics, and make recommendations on the design and prioritization of future clinical trials. CP7 considers limited duration and novel-novel agent combinations to be the priority for the next generation of clinical trials. Evaluation of MYD88, CXCR4 and TP53 at baseline in the context of clinical trials is crucial. The common chemoimmunotherapy backbones, bendamustine-rituximab (BR) and dexamethasone, rituximab and cyclophosphamide (DRC), may be considered standard-of-care for the frontline comparative studies. Key unanswered questions include the definition of frailty in WM; the importance of attaining a very good partial response or better (≥VGPR), within stipulated time frame, in determining survival outcomes; and the optimal treatment of WM populations with special needs.

Lenalidomide plus R-CHOP21 in newly diagnosed diffuse large B-cell lymphoma (DLBCL): long-term follow-up results from a combined analysis from two phase 2 trials.

Lenalidomide-RCHOP (R2-CHOP21) has been shown to be safe and effective in patients with untreated diffuse large B-cell lymphoma (DLBCL). The aim of this analysis is to report long-term outcome and toxicities in newly diagnosed DLBCL patients who received R2-CHOP21 in two independent phase 2 trials, conducted by Mayo Clinic (MC) and Fondazione Italiana Linfomi (FIL). All patients received R-CHOP21 plus lenalidomide. Long-term progression-free survival (PFS), time to progression (TTP), overall survival (OS) and late toxicities and second tumors were analyzed. Hundred and twelve patients (63 MC, 49 FIL) were included. Median age was 69 years, 88% were stage III-IV. At a median follow-up of 5.1 years, 5y-PFS was 63.5%, 5y-TTP 70.1% and 5y-OS 75.4%; according to cell of origin (COO): 5y-PFS 52.8% vs 64.5%, 5y-TTP 61.6% vs 69.6% and 5y-OS 68.6% vs 74.1% in germinal center (GCB) vs non-GCB respectively. Four patients experienced grade 4-5 late toxicities. Grade ≤ 3 toxicities were infections (N = 4), thrombosis (N = 1) and neuropathy (N = 3). Seven seconds tumors were observed. Long-term follow-up demonstrates that R2-CHOP21 efficacy was maintained with high rates of PFS, TTP, and OS. Lenalidomide appears to mitigate the negative prognosis of non-GCB phenotype. Incidence of therapy-related secondary malignancies and late toxicities were low.

Infusion of autograft natural killer cell/CD14+HLA-DRDIM cell ratio predicts survival in lymphoma post autologous stem cell transplantation.

The infusion of autograft absolute lymphocyte count (A-ALC) and autograft natural killer cells (A-NKC) are prognostic factors for overall survival (OS) and PFS in non-Hodgkin's lymphoma (NHL) patients undergoing autologous peripheral blood hematopoietic stem cell transplantation (APBHSCT). The human monocytic CD14+HLA-DRDIM cells are associated with worse prognosis in NHL. Thus, we investigated whether the autograft A-NKC/A-CD14+HLA-DRDIM ratio predicts survival in NHL. In a total of 111 NHL patients, we analyzed apheresis collection samples for the content of A-NKC and A-CD14+HLA-DRDIM. With a median follow-up of 57.2 months (range: 2.1-84.6 months), patients with an A-NKC/A-CD14+HLA-DRDIM ratio of ⩾0.29 experienced superior OS (5-year OS rates of 84% (95% confidence interval (CI), 72-91%) vs 48% (95% CI, 34-62%), P<0.0002, respectively) and PFS (5-year PFS rates of 59% (95% CI, 47-71%) vs 32% (95% CI, 20-48%), P<0.002, respectively). Multivariate analysis revealed that A-NKC/A-CD14+HLA-DRDIM ratio was an independent predictor for PFS (hazard ratio (HR)=0.56, 95% CI, 0.32-0.96, P<0.03) and OS (HR=0.34, 95% CI, 0.16-0.68, P<0.002). The A-NKC/A-CD14+HLA-DRDIM ratio provides a platform to target specific autograft immune effector cells to improve clinical outcomes in NHL patients undergoing APBHSCT.

A phase 1 trial of 90Y-Zevalin radioimmunotherapy with autologous stem cell transplant for multiple myeloma.

This phase 1 study (clinical trial NCT00477815) was conducted to determine the maximum tolerated dose (MTD) of yttrium-90 ibritumomab tiuxetan (90Y-Zevalin) with high dose melphalan (HDM) therapy in multiple myeloma (MM) patients undergoing autologous stem cell transplantation (ASCT). In a 3+3 trial design, 30 patients received rituximab 250 mg/m2 with indium-111 ibritumomab tiuxetan (111In-Zevalin) for dosimetry (day -22); rituximab 250 mg/m2 with escalating doses of 90Y-Zevalin (day -14); melphalan 100 mg/m2 (days -2,-1) followed by ASCT (day 0) and sargramostim (GM-CSF, day 0) until neutrophil engraftment. Each patient's 111In-Zevalin dosimetry data were used to calculate the dose of 90Y-Zevalin (in mCi) to deliver 10, 12, 14, 16, 18 or 20 Gy to the liver. Dose limiting toxicities were seen in 3 patients. The overall response rate was 73% (22/30) with stringent complete response in 2 patients; complete response, 5; very good partial response, 12; and partial response, 3. The median PFS was 16.5 months and the median overall survival was 63.4 months. In MM, the MTD of 90Y-Zevalin with HDM is 18 Gy to the liver. The addition of radiation with novel delivery methods such as radioimmunotherapy combined with standard transplant regimens warrants further study.

Vitamin D insufficiency is associated with an increased risk of early clinical failure in follicular lymphoma.

We evaluated whether vitamin D insufficiency (VDI; 25(OH)D <20 ng/ml) was associated with adverse outcomes among follicular lymphoma (FL) patients using an observational prospective cohort study of 642 FL patients enrolled from 2002-2012. The median age at diagnosis was 60 years. At a median follow-up of 59 months, 297 patients (46%) had an event (progression, treatment failure), 78 had died and 42 (6.5%) had a lymphoma-related death. VDI was associated with inferior event-free survival (EFS) at 12 months (EFS12, odds ratio (OR)=2.05; 95% confidence interval (CI) 1.18-3.54), overall survival (OS, hazards ratio (HR)=2.35; 95%CI 1.37-4.02), and lymphoma-specific survival (LSS, HR=2.97; 95% CI 1.52-5.80) for the full cohort. Among patients treated with immunochemotherapy (IC), VDI was associated with inferior EFS12 (OR=3.00; 95% CI 1.26-7.13), OS (HR=2.86; 95% CI 1.39-5.85), and LSS (HR=2.96; 95% CI 1.29-6.79). For observed patients, VDI was associated with inferior OS (HR=2.85; 95% CI 1.20-6.76). For other therapies, VDI was associated with inferior OS (HR=3.06; 95% CI 1.01-9.24). Our work is the first to reveal an association of VDI with early clinical failure, and to demonstrate an association of VDI with adverse outcomes among patients who are observed or treated with therapies other than IC. Our findings suggest a potentially modifiable prognostic factor to address in patients with FL.

International Working Group consensus response evaluation criteria in lymphoma (RECIL 2017).

In recent years, the number of approved and investigational agents that can be safely administered for the treatment of lymphoma patients for a prolonged period of time has substantially increased. Many of these novel agents are evaluated in early-phase clinical trials in patients with a wide range of malignancies, including solid tumors and lymphoma. Furthermore, with the advances in genome sequencing, new "basket" clinical trial designs have emerged that select patients based on the presence of specific genetic alterations across different types of solid tumors and lymphoma. The standard response criteria currently in use for lymphoma are the Lugano Criteria which are based on [18F]2-fluoro-2-deoxy-D-glucose positron emission tomography or bidimensional tumor measurements on computerized tomography scans. These differ from the RECIST criteria used in solid tumors, which use unidimensional measurements. The RECIL group hypothesized that single-dimension measurement could be used to assess response to therapy in lymphoma patients, producing results similar to the standard criteria. We tested this hypothesis by analyzing 47 828 imaging measurements from 2983 individual adult and pediatric lymphoma patients enrolled on 10 multicenter clinical trials and developed new lymphoma response criteria (RECIL 2017). We demonstrate that assessment of tumor burden in lymphoma clinical trials can use the sum of longest diameters of a maximum of three target lesions. Furthermore, we introduced a new provisional category of a minor response. We also clarified response assessment in patients receiving novel immune therapy and targeted agents that generate unique imaging situations.

Experimental verification of spallation inventory calculations.

Monte Carlo calculations and gamma-ray spectrometry measurements have been made for a highly irradiated tungsten target from a proton-driven spallation neutron source. A comparison of the calculated and measured activities of 60Co and 172Lu in the radionuclide inventory shows surprisingly good agreement.

Coinhibition of the deubiquitinating enzymes, USP14 and UCHL5, with VLX1570 is lethal to ibrutinib- or bortezomib-resistant Waldenstrom macroglobulinemia tumor cells.

The survival of Waldenstrom macroglobulinemia (WM) tumor cells hinges on aberrant B-cell receptor (BCR) and MYD88 signaling. WM cells upregulate the proteasome function to sustain the BCR-driven growth while maintaining homeostasis. Clinically, two treatment strategies are used to disrupt these complementary yet mutually exclusive WM survival pathways via ibrutinib (targets BTK/MYD88 node) and bortezomib (targets 20 S proteasome). Despite the success of both agents, WM patients eventually become refractory to treatment, highlighting the adaptive plasticity of WM cells and underscoring the need for development of new therapeutics. Here we provide a comprehensive preclinical report on the anti-WM activity of VLX1570, a novel small-molecule inhibitor of the deubiquitinating enzymes (DUBs), ubiquitin-specific protease 14 (USP14) and ubiquitin carboxyl-terminal hydrolase isozyme L5 (UCHL5). Both DUBs reside in the 19 S proteasome cap and their inhibition by VLX1570 results in rapid and tumor-specific apoptosis in bortezomib- or ibrutinib-resistant WM cells. Notably, treatment of WM cells with VLX1570 downregulated BCR-associated elements BTK, MYD88, NFATC, NF-κB and CXCR4, the latter whose dysregulated function is linked to ibrutinib resistance. VLX1570 administered to WM-xenografted mice resulted in decreased tumor burden and prolonged survival (P=0.0008) compared with vehicle-treated mice. Overall, our report demonstrates significant value in targeting USP14/UCHL5 with VLX1570 in drug-resistant WM and carries a high potential for clinical translation.

Whole-exome analysis reveals novel somatic genomic alterations associated with outcome in immunochemotherapy-treated diffuse large B-cell lymphoma.

Lack of remission or early relapse remains a major clinical issue in diffuse large B-cell lymphoma (DLBCL), with 30% of patients failing standard of care. Although clinical factors and molecular signatures can partially predict DLBCL outcome, additional information is needed to identify high-risk patients, particularly biologic factors that might ultimately be amenable to intervention. Using whole-exome sequencing data from 51 newly diagnosed and immunochemotherapy-treated DLBCL patients, we evaluated the association of somatic genomic alterations with patient outcome, defined as failure to achieve event-free survival at 24 months after diagnosis (EFS24). We identified 16 genes with mutations, 374 with copy number gains and 151 with copy number losses that were associated with failure to achieve EFS24 (P<0.05). Except for FOXO1 and CIITA, known driver mutations did not correlate with EFS24. Gene losses were localized to 6q21-6q24.2, and gains to 3q13.12-3q29, 11q23.1-11q23.3 and 19q13.12-19q13.43. Globally, the number of gains was highly associated with poor outcome (P=7.4 × 10(-12)) and when combined with FOXO1 mutations identified 77% of cases that failed to achieve EFS24. One gene (SLC22A16) at 6q21, a doxorubicin transporter, was lost in 54% of EFS24 failures and our findings suggest it functions as a doxorubicin transporter in DLBCL cells.

IL-10 induces the development of immunosuppressive CD14(+)HLA-DR(low/-) monocytes in B-cell non-Hodgkin lymphoma.

The biological role of monocytes and macrophages in B-cell non-Hodgkin lymphoma (NHL) is not fully understood. We have previously reported that monocytes from patients with B-cell NHL have an immunosuppressive CD14(+)HLA-DR(low/-) phenotype that correlates with a poor prognosis. However, the underlying mechanism by which CD14(+)HLA-DR(low/-) monocytes develop in lymphoma is unknown. In the present study, we found that interleukin (IL)-10, which is increased in the serum of patients with B-cell NHL, induced the development of the CD4(+)HLA-DR(low/-) population. Using peripheral blood samples from patients with B-cell NHL, we found that absolute numbers of CD14(+) monocytic cells with an HLA-DR(low/-) phenotype were higher than healthy controls and correlated with a higher International Prognostic Index score. IL-10 serum levels were elevated in lymphoma patients compared with controls and were associated with increased peripheral monocyte counts. Treatment of monocytes with IL-10 in vitro significantly decreased HLA-DR expression and resulted in the expansion of CD14(+)HLA-DR(low/-) population. We found that lymphoma B cells produce IL-10 and supernatants from cultured lymphoma cells increased the CD14(+)HLA-DR(low/-) population. Furthermore, we found that IL-10-induced CD14(+)HLA-DR(low/-) monocytes inhibited the activation and proliferation of T cells. Taken together, these results suggest that elevated IL-10 serum levels contribute to increased numbers of immunosuppressive CD14(+)HLA-DR(low/-) monocytes in B-cell NHL.

PD-1 expression defines two distinct T-cell sub-populations in follicular lymphoma that differentially impact patient survival.

To determine the biological and clinical relevance of programmed death 1 (PD-1) in follicular lymphoma (FL), we characterized PD-1(+) T-cell subsets and assessed their biological function as well as potential clinical impact. We found that PD-1 is expressed on intratumoral CD4(+) T cells with both bright and dim intensity, representing two different sub-populations of cells. By immunohistochemistry, we found that CD4(+)PD-1(high) T cells predominantly reside in the lymph node follicles, while PD-1(low) T cells are mainly located in an interfollicular pattern. Intratumoral CD4(+)PD-1(high) T cells have a TFH cell phenotype, express CXCR5, secrete IL-21 and are BCL-6 positive with no TIM-3 expression. In contrast, CD4(+)PD-1(low) T cells have an exhausted phenotype, express TIM-3 and do not express BCL-6 and CXCR5. Functionally, CD4(+)PD-1(high) T cells actively supported B-cell growth, while CD4(+)PD-1(low) T cells displayed a reduced cytokine production and cell-signal transduction. Clinically, we observed that the numbers of CD4(+) or CD8(+)PD-1(low) T cells significantly correlate with a reduced overall survival in FL patients (P=0.007 and 0.04 respectively; n=32). In contrast, the number of CD4(+)PD-1(high) T cells was not associated with patient outcome. Taken together, these results indicated that PD-1 expression defines two sub-populations with distinct functions that differentially impact patient outcome in FL.

Neutron scattering studies of the hydration structure of Li+.

New results derived from the experimental method of neutron diffraction and isotopic substitution (NDIS) are presented for the hydration structure of the lithium cation (Li(+)) in aqueous solutions of lithium chloride in heavy water (D2O) at concentrations of 6, 3, and 1 m and at 1.5 m lithium sulfate. By introducing new and more-accurate data reduction procedures than in our earlier studies (I. Howell and G. W. Neilson, J. Phys: Condens. Matter, 1996, 8, 4455-4463), we find, in the first hydration shell of Li(+), ∼4.3(2) water molecules at 6 m, 4.9(3) at 3 m, 4.8(3) at 1 m in the LiCl solutions, and 5.0(3) water molecules in the case of Li2SO4 solution. The general form of the first hydration shell is similar in all four solutions, with the correlations for Li-O and Li-D sited at 1.96 (0.02) Å and 2.58 (0.02) Å, respectively. The results resemble those presented in 1996, in terms of ion-water distances and local coordination, but the hydration number is significantly lower for the case at 1 m than the 6.5 (1.0) given at that time. Thus, experimental and theoretical results now agree that lithium is hydrated by a small number of water molecules (4-5) in the nearest coordination shell.

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

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

The role of front-line anthracycline-containing chemotherapy regimens in peripheral T-cell lymphomas.

Peripheral T-cell lymphomas (PTCLs) are a heterogenous group of aggressive non-Hodgkin's lymphomas that are incurable in the majority of patients with current therapies. Outcomes associated with anthracycline-based therapies are suboptimal, but remain the standard of care for most patients, even though the benefits of this approach remain uncertain. This study retrospectively examined outcomes in a cohort of North American PTCL patients treated with both anthracycline- and nonanthracycline-containing regimens. The incorporation of anthracycline-containing regimens was associated with improved progression-free survival (PFS) and overall survival (OS). Patients treated with nonanthracycline-containing regimens were more likely to have high-risk features and were less likely to undergo high-dose therapy and stem cell transplantation. However, anthracycline use remained an independent predictor of improved PFS and OS when adjusting for these confounding variables. Anthracycline-based regimens and consolidation with high-dose therapy and autologous stem cell transplantation in appropriately selected patients remains a viable option for patients unable to participate in a clinical trial. Long-term disease-free survival is not optimal, highlighting the need for an improved understanding of disease pathogenesis, and the development of novel therapeutic strategies.

Accuracy of self-reported tobacco use status among hematopoietic SCT patients.

Tobacco use is a risk factor for adverse outcomes among hematopoietic SCT (HSCT) patients. Accurate identification of tobacco use offers a vital opportunity to treat this risk factor. The current study compared self-reported tobacco use status with serum cotinine levels among HSCT patients at the time of pre-transplant evaluation. A total of 444 participants completed both assessments; 44 participants (9.9%) were classified as tobacco users with serum cotinine concentrations >2 ng/mL vs 29 with self-reporting. Sensitivity and specificity of self-reporting were 65.9% and 100%, respectively. Positive and negative predictive values were 100% and 96.4%, respectively. Comparing tobacco use documented in the medical record with cotinine, sensitivity and specificity were 51.2% and 99.2%, respectively. Factors associated with tobacco use were male gender, single relationship status, less education and younger age. In summary, utilization of serum cotinine assays increased detection of tobacco use cases >50% over self-reporting. Results are discussed in the context of translation to care, including clinical and ethical implications, and current tobacco use treatment guidelines. When cotinine assays are not available, self-reporting of any tobacco use in the year before HSCT should trigger brief advice and cessation or relapse prevention counseling.

Activation of TAK1 by MYD88 L265P drives malignant B-cell Growth in non-Hodgkin lymphoma.

Massively parallel sequencing analyses have revealed a common mutation within the MYD88 gene (MYD88L265P) occurring at high frequencies in many non-Hodgkin lymphomas (NHLs) including the rare lymphoplasmacytic lymphoma, Waldenström's macroglobulinemia (WM). Using whole-exome sequencing, Sanger sequencing and allele-specific PCR, we validate the initial studies and detect the MYD88L265P mutation in the tumor genome of 97% of WM patients analyzed (n=39). Due to the high frequency of MYD88 mutation in WM and other NHL, and its known effects on malignant B-cell survival, therapeutic targeting of MYD88 signaling pathways may be clinically useful. However, we are lacking a thorough characterization of the role of intermediary signaling proteins on the biology of MYD88L265P-expressing B cells. We report here that MYD88L265P signaling is constitutively active in both WM and diffuse large B-cell lymphoma cells leading to heightened MYD88L265P, IRAK and TRAF6 oligomerization and NF-κB activation. Furthermore, we have identified the signaling protein, TAK1, to be an essential mediator of MYD88L265P-driven signaling, cellular proliferation and cytokine secretion in malignant B cells. Our studies highlight the biological significance of MYD88L265P in NHL and reveal TAK1 inhibition to be a potential therapeutic strategy for the treatment of WM and other diseases characterized by MYD88L265P.