Next-CLL: A New Next-Generation Sequencing-Based Method for Assessment of IGHV Gene Mutational Status in Chronic Lymphoid Leukemia

Current guidelines for patients with chronic lymphocytic leukemia (CLL) recommend mutation status determination of the clonotypic IGHV gene before treatment initiation to guide the choice of first-line therapy. Currently, commercially available next-generation sequencing (NGS) solutions have technical constraints, as they necessitate at least a 2 × 300 bp sequencing, which restricts their use for routine practice. The cost of the commercial kits also represents an important drawback. We present a new method called Next-CLL, a ready-to-use strategy to evaluate IGHV gene mutation status using any NGS device (including 2 × 150 bp sequencers) in routine diagnostic laboratories. The performance of Next-CLL was validated on genomic DNA and cDNA obtained from 80 patients with CLL at diagnosis. Next-CLL identified a productive clone in 100% of cases, whereas PCR with Sanger sequencing led to a 12.5% failure rate. Next-CLL had 100% concordance with the reference technique for IGHV gene identification and allowed assessment of the IGHV mutation status from the leader sequence, following international guidelines. Comparing a large retrospective series of samples, analyzed by using Sanger sequencing (n = 773) or Next-CLL (n = 352), showed no bias in IGHV usage or mutational status, further validating our strategy in the real-life setting. Next-CLL represents a straightforward workflow for IGHV analysis in routine practice to assess clonal architecture and prognosis of patients with CLL.

Toward a pathophysiology inspired treatment of VEXAS syndrome

VEXAS syndrome has an unmet need for therapeutic interventions. Even if few data exist regarding the treatment of this newly described syndrome, different options can be proposed given the unique pathophysiological consequences of the clonal dominance of UBA1 mutated hematopoietic stem cells. To date, allogeneic transplantation is the only curative option, but many questions remain regarding the selection of eligible patients, the conditioning regimen or management of toxicities that may be unique to VEXAS patients. Alternatively, drugs used in myelodysplastic syndrome such as hypomethylating agents or lenalidomide are interesting candidates, which could theoretically have also an effect on the clone. Another strategy is to target the inflammatory cascade, by inhibiting proinflammatory cytokines (such as TNFα, IL1, IL6) or effector cells, for example with JAK inhibitors. Whatever the choice of treatment for VEXAS patients, supportive care is always needed to be considered to manage frequent complications such as cytopenia, thrombosis and infections. Finally, we discuss the challenges of the design of clinical trials for VEXAS patients, from inclusion criteria to clinical and biological endpoints of activity.

Clinicopathological features and survival in EBV-positive diffuse large B-cell lymphoma not otherwise specified

In this retrospective study, we report 70 cases of Epstein-Barr virus (EBV)+ diffuse large B-cell lymphoma not otherwise specified (DLBCL-NOS) among 1696 DLBCL-NOS cases diagnosed between 2006 and 2019 (prevalence of 4.1%). At diagnosis, median age was 68.5 years; 79% of the cases presented with an advanced-stage disease (III-IV), 48% with extranodal lesions, and 14% with an hemophagocytic lymphohistiocytosis (HLH) (8 at diagnosis and 1 on therapy). A total of 46 cases presented a polymorphic pattern, and 21 were monomorphic. All had a non-germinal center B phenotype, with the majority of tumor cells expressing CD30 and programmed death ligand 1 (98% and 95%, respectively). Type II and III EBV latency was seen in 88% and 12% of the cases, respectively. Patients were treated with immunochemotherapy (59%) or chemotherapy (22%), and 19% received palliative care due to advanced age and altered performance status. After a median follow-up of 48 months, progression-free survival (PFS) and overall survival (OS) at 5 years were 52.7% and 54.8%, respectively. Older age (>50 years) and HLH were associated with shorter PFS and OS in multivariate analysis (PFS: hazard ratio [HR], 14.01; 95% confidence interval [CI], 2.34-83.97; and HR, 5.78; 95% CI, 2.35-14.23; OS: HR, 12.41; 95% CI, 1.65-93.53; and HR, 6.09; 95% CI, 2.42-15.30, respectively). Finally, using a control cohort of 425 EBV- DLBCL-NOS, EBV positivity was associated with a shorter OS outcome within patients >50 years (5-year OS, 53% [95% CI, 38.2-74] vs 60.8% [95% CI, 55.4-69.3], P = .038), but not in younger patients.

Real-life targeted next-generation sequencing for lymphoma diagnosis over 1 year from the French Lymphoma Network

As the impact of targeted next-generation sequencing (TNGS) on daily diagnosis has not been evaluated, we performed TNGS (46 genes) on lymphomas of unclear subtype following expert haematopathological review. The potential impact on patient care and modifications of final diagnosis were divided into major and minor changes according to the European Society of Medical Oncology (ESMO) guidelines. Among 229 patients [19 primary central nervous system lymphomas (PCNSL), 48 large B-cell lymphomas (LBCLs), 89 small BCLs (SBCLs), seven Hodgkin lymphomas (HL), 66 T-cell lymphomas], the overall concordance rate of histological and TNGS diagnosis was 89·5%. TNGS confirmed the histological diagnosis in 144 cases (62·9%), changed the diagnosis in 24 cases (10·5%) and did not help to clarify diagnosis in 61 cases (26·7%). Modifications to the final diagnosis had a clinical impact on patient care in 8·3% of cases. Diagnostic modifications occurred in all types of lymphoma except in PCNSL and HL; the modification rate was 14·6% in SBCL and 12·5% in LBCL. While comparing informative and uninformative cases, no differences were found in terms of DNA amplification, quality or depth of sequencing and biopsy type. The present study highlights that TNGS may directly contribute to a more accurate diagnosis in difficult-to-diagnose lymphomas, thus improving the clinical management in routine practice.

Polatuzumab vedotin: an investigational anti-CD79b antibody drug conjugate for the treatment of diffuse large B-cell lymphoma

INTRODUCTION

New agents for managing B-cell non-Hodgkin lymphomas (NHLs) are needed, particularly for high-risk and relapsed or refractory patients. Antibody-drug conjugates (ADCs) provide targeted drug delivery to tumors with a broaden therapeutic index of cytotoxic agent, reducing their systemic toxicity while increasing intracellular concentrations. Polatuzumab vedotin, an anti-CD79b conjugated to the microtubule inhibitor monomethyl auristatin E (MMAE) raises particular interest.

AREAS COVERED

We discuss here polatuzumab vedotin development, challenges of designing a successful ADC, preclinical studies and recent trials, leading to FDA approval and the ongoing phase III POLARIX trial.

EXPERT OPINION

Clinical data from early studies hold promises for polatuzumab vedotin in association with rituximab-bendamustine in relapsed or refractory (R/R) DLBCL and other combinations are investigated in this setting. In first line, with rituximab, cyclophosphamide, doxorubicin and prednisone (R-CHP), promising results lead to develop the phase III POLARIX trial that may represent a new advance for untreated patients. If dosing and scheduling are adequately managed to avoid peripheral neuropathy risk, polatuzumab vedotin might become a key component of DLBCL therapeutic management. This antibody drug conjugate also offers new opportunities of combination with non-cytotoxic agents or immunological interventions that might reshape the treatment of DLBCL in the future.

Refractory diffuse large B-cell lymphoma after first-line immuno-CT: Treatment options and outcomes

In the rituximab era, one-third of diffuse large B-cell lymphoma patients experience relapse/refractory disease after first-line anthracycline-based immunochemotherapy. Optimal management remains an unmet medical need. The aim of this study was to report the outcomes of a cohort of refractory patients according to their patterns of refractoriness and the type of salvage option. We performed a retrospective analysis, which included 104 diffuse large B-cell lymphoma patients treated at Lyon Sud University Hospital (2002-2017) who presented with refractory disease. Refractoriness was defined as progressive/stable disease during first-line treatment (primary refractory, N = 47), a partial response after the end of first-line treatment that required subsequent treatment (residual disease, N = 19), or relapse within 1 year of diagnosis after an initial complete response (CR) (early relapse, N = 38). The 2-year overall survival (OS) rates for primary refractory, early relapse, and residual disease patients were 27%, 25%, and 52%, respectively, while the event-free survival rates for those groups were 13%, 13%, and 42%, respectively. In a univariate analysis, lactate dehydrogenase level, Ann Arbor stage, poor performance status, high age-adjusted International Prognostic Index score, and age > 65 years were associated with shorter OS. The use of rituximab and platinum-based chemo during the first salvage treatment was associated with prolonged OS. In a multivariate analysis, age (HR:2.06) and rituximab use (HR:0.54) were associated with OS. Among patients <65 years who achieved a CR, autologous stem-cell transplant was associated with higher 2-year OS (90% vs 74%, P = 0.10). Patients who were treated with a targeted therapy in the context of a clinical trial after second-line treatment had a higher 2-year OS (34% vs 19%, P = 0.06). In conclusion, patients with primary refractory disease or early relapse have very poor outcomes but may benefit from rituximab retreatment during the first salvage treatment.

Delayed methotrexate elimination: Incidence, interaction with antacid drugs, and clinical consequences?

The aim of this retrospective cohort study was to investigate the incidence of delayed methotrexate elimination in patients treated with high-dose methotrexate (≥1 g/m² ) for haematological malignancy and to identify the impact of interacting drugs, especially proton-pump inhibitors (PPIs) and ranitidine. All patients treated with high-dose methotrexate over a 6 year period in the haematology department of the Lyon Sud University Hospital (Hospices Civils de Lyon, France) were included. Potential risk factors for delayed methotrexate elimination were tested in a generalized linear model by univariate analysis: patient age, gender, methotrexate dose, administration of PPI or ranitidine, and concomitant nephrotoxic drugs. A total of 412 cycles of methotrexate were administered to 179 patients. Proton-pump inhibitors were co-administered with methotrexate in 127 cycles and ranitidine in 192 cycles. Ninety-three cycles included no antacid drugs. A total of 918 plasma methotrexate assays were performed. Methotrexate concentrations were checked at 24 hours in 92% of cycles. Delayed methotrexate elimination was observed in 20.9% of cycles. A total of 63 cycles with delayed methotrexate elimination were only identified on plasma methotrexate measures at 72 hours: ie, plasma methotrexate was in the normal range at 24 and 48 hour post injection. Use of PPI/ranitidine or no antacid drugs did not increase risk of delayed elimination, with respectively delayed methotrexate elimination in 20.5%, 21.9%, and 19.4% of cycles (P = .89). Impaired baseline creatinine clearance showed significant association in univariate analysis. Fifteen patients showed grade 1 acute kidney injury, 1 grade 2, 2 grade 3, and none grade 4. For half of these cases, delayed methotrexate elimination was observed and the 2 grade 3 events appeared in patients treated with PPIs. This retrospective study suggests that there is no association between concomitant use of proton-pump inhibitors (pantoprazole and esomeprazole) or ranitidine and delayed methotrexate elimination.