A phase 1 study of ibrutinib in combination with R-ICE in patients with relapsed or primary refractory DLBCL

Preclinical evidence for the effective use of TL-895, a highly selective and potent second-generation BTK inhibitor, for the treatment of B-cell malignancies

TL-895 (formerly known as M7583) is a potent, highly selective, adenosine triphosphate (ATP)-competitive, second-generation, irreversible inhibitor of Bruton's tyrosine kinase (BTK). We characterized its biochemical and cellular effects in in vitro and in vivo models. TL-895 was evaluated preclinically for potency against BTK using IC50 concentration-response curves; selectivity using a 270-kinase panel; BTK phosphorylation in Ramos Burkitt's lymphoma cells by ProteinSimple Wes analysis of one study; anti-proliferative effects in primary chronic lymphocytic leukemia (CLL) blasts; cell viability effects in diffuse large B-cell lymphoma (DLBCL) and mantle-cell lymphoma (MCL) cell lines; effects on antibody-dependent cell-mediated cytotoxicity (ADCC) from Daudi cells and chromium-51 release from human tumor cell lines; and efficacy in vivo using four MCL xenograft model and 21 DLBCL patient-derived xenograft (PDX) models (subtypes: 9 ABC, 11 GCB, 1 Unclassified). TL-895 was active against recombinant BTK (average IC50 1.5 nM) and inhibited only three additional kinases with IC50 within tenfold of BTK activity. TL-895 inhibited BTK auto-phosphorylation at the Y223 phosphorylation site (IC50 1-10 nM). TL-895 inhibited the proliferation of primary CLL blasts in vitro and inhibited growth in a subset of activated DLBCL and MCL cell lines. TL-895 inhibited the ADCC mechanism of therapeutic antibodies only at supra-clinical exposure levels. TL-895 significantly inhibited tumor growth in the Mino MCL xenograft model and in 5/21 DLBCL PDX models relative to vehicle controls. These findings demonstrate the potency of TL-895 for BTK and its efficacy in models of B-cell lymphoma despite its refined selectivity.

Lenalidomide in combination with R-ESHAP in patients with relapsed or refractory diffuse large B-cell lymphoma: A phase 2 study from GELTAMO

Diffuse large B-cell lymphoma (DLBCL) patients with relapsed or refractory (RR) disease have poor outcomes with current salvage regimens. We conducted a phase 2 trial to analyse the safety and efficacy of adding lenalidomide to R-ESHAP (LR-ESHAP) in patients with RR DLBCL. Subjects received 3 cycles of lenalidomide 10 mg/day on days 1-14 of every 21-day cycle, in combination with R-ESHAP at standard doses. Responding patients underwent autologous stem-cell transplantation (ASCT). The primary endpoint was the overall response rate (ORR) after 3 cycles. Centralized cell-of-origin (COO) classification was performed. Forty-six patients were included. The ORR after LR-ESHAP was 67% (35% of patients achieved complete remission). Patients with primary refractory disease (n = 26) had significantly worse ORR than patients with non-refractory disease (54% vs. 85%, p = 0.031). No differences in response rates according to the COO were observed. Twenty-eight patients (61%) underwent ASCT. At a median follow-up of 41 months, the estimated 3-year PFS and OS were 42% and 48%, respectively. The most common grade ≥3 adverse events were thrombocytopenia (70% of patients), neutropenia (67%) and anaemia (35%). There were no treatment-related deaths during LR-ESHAP cycles. In conclusion, LR-ESHAP is a feasible salvage regimen with promising efficacy results for patients with RR DLBCL.

Ibrutinib plus RICE or RVICI for relapsed/refractory mature B-cell non-Hodgkin lymphoma in children and young adults: SPARKLE trial

Part 1 results of the open-label, randomized, global phase 3 SPARKLE trial supported continued assessment of ibrutinib with either modified rituximab, ifosfamide, carboplatin, and etoposide (RICE) or rituximab, vincristine, ifosfamide, carboplatin, idarubicin, and dexamethasone (RVICI) in pediatric patients with relapsed/refractory (R/R) mature B-cell non-Hodgkin lymphoma (B-NHL). We report final results of Part 2 evaluating the efficacy of ibrutinib plus RICE or RVICI vs RICE/RVICI alone. Patients aged 1 to 30 years (initial diagnosis <18 years) were randomized 2:1 to receive ibrutinib with or without RICE/RVICI. Primary endpoint was event-free survival (EFS) based on independent committee-confirmed events. Fifty-one patients were enrolled. Median age was 15 years; Burkitt lymphoma, Burkitt leukemia, and Burkitt-like lymphoma (total: 45%) and diffuse large B-cell lymphoma/primary mediastinal B-cell lymphoma (51%) were the most common subtypes. At the preplanned interim analysis, median EFS was 6.1 vs 7.0 months with ibrutinib plus RICE/RVICI vs RICE/RVICI, respectively (hazard ratio, 0.9; 90% confidence interval, 0.5-1.6; P = .387); further enrollment was ceased. With ibrutinib plus RICE/RVICI vs RICE/RVICI, median overall survival was 14.1 vs 11.1 months, overall response rate was 69% vs 81%, and 46% vs 44% proceeded to stem cell transplantation. In both treatment arms, 100% of patients experienced grade ≥3 treatment-emergent adverse events. No EFS benefit was seen with ibrutinib. Salvage was generally poor in patients who received prior rituximab, regardless of treatment arm. No new safety signals were observed. Ibrutinib exposure in pediatric patients fell within the target range of exposure in adults. Trial is registered on www.clinicaltrials.gov (NCT02703272).

Development and validation of a [18F]FDG PET/CT-based radiomics nomogram to predict the prognostic risk of pretreatment diffuse large B cell lymphoma patients

Objective

In this study, based on PET/CT radiomics features, we developed and validated a nomogram to predict progression-free survival (PFS) for cases with diffuse large B cell lymphoma (DLBCL) treated with immunochemotherapy.

Methods

This study retrospectively recruited 129 cases with DLBCL. Among them, PET/CT scans were conducted and baseline images were collected for radiomics features along with their clinicopathological features. Radiomics features related to recurrence were screened for survival analysis using univariate Cox regression analysis with p < 0.05. Next, a weighted Radiomics-score (Rad-score) was generated and independent risk factors were obtained from univariate and multivariate Cox regressions to build the nomogram. Furthermore, the nomogram was tested for their ability to predict PFS using time-dependent receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

Results

Blood platelet, Rad-score, and gender were included in the nomogram as independent DLBCL risk factors for PFS. We found that the training cohort areas under the curve (AUCs) were 0.79, 0.84, and 0.88, and validation cohort AUCs were 0.67, 0.83, and 0.72, respectively. Further, the DCA and calibration curves confirmed the predictive nomogram’s clinical relevance.

Conclusion

Using Rad-score, blood platelet, and gender of the DLBCL patients, a PET/CT radiomics-based nomogram was developed to guide cases’ recurrence risk assessment prior to treatment. The developed nomogram can help provide more appropriate treatment plans to the cases.

Key Points

• DLBCL cases can be classified into low- and high-risk groups using PET/CT radiomics based Rad-score.

• When combined with other clinical characteristics (gender and blood platelet count), Rad-score can be used to predict the outcome of the pretreatment of DLBCL cases with a certain degree of accuracy.

• A prognostic nomogram was established in this study in order to aid in assessing prognostic risk and providing more accurate treatment plans for DLBCL cases.

Zanubrutinib plus salvage chemotherapy for relapsed or refractory diffuse large B-cell lymphoma

Introduction

Relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL) has poor clinical outcomes when treated with conventional salvage chemotherapy. Monotherapy using zanubrutinib, a selective Bruton's tyrosine kinase (BTK) inhibitor, has achieved modest antitumor effect in R/R DLBCL. Here we aimed to evaluate the efficacy and safety of zanubrutinib plus salvage chemotherapy in R/R DLBCL patients.

Methods

We retrospectively reviewed R/R DLBCL patients who were administered with zanubrutinib plus salvage chemotherapy in our center between January, 2019 and December, 2021. Targeted panel sequencing of 11 lymphoma-related genes was performed on 8 patients with poor responses to zanubrutinib-based chemotherapy.

Results

27 R/R DLBCL patients were enrolled. Median age at this study was 59 years (range, 15-72). The best overall response rate (ORR) was 74.1% and complete remission rate was 33.3%. With a median follow-up of 11 months (range, 1-17), the median progression-free survival (PFS) was 8.1 months, and the overall survival (OS) was not achieved. The most common grade-3/4 adverse events were neutropenia (70.4%), thrombocytopenia (66.7%), and febrile neutropenia (33.3%). In multivariate analysis, early treatment and overall response after chemotherapy were independent favorable prognostic factors for PFS. Overall response after chemotherapy was an independent favorable factor for OS. Among the 8 patients with poor response to zanubrutinib-based treatment, the majority of patients had NOTCH2 mutations (n=8, 100%) and TP53 mutations (n=7, 87.5%). However, these patients achieved an ORR of 75% at 3 months after CD19-CAR-T cell therapy (including 4 cases of complete remission and 2 cases of partial remission). With a median follow-up of 9 months from CAR-T cell infusion (range, 1-16 months), the median PFS was 14.5 months, and the median OS was not reached.

Conclusion

With high efficacy and manageable tolerability, zanubrutinib plus salvage chemotherapy may be a potential treatment option for R/R DLBCL. CAR-T cell therapy may be a priority strategy for these poor responders to BTKi-based treatment.

BTK inhibitors in the treatment of hematological malignancies and inflammatory diseases: mechanisms and clinical studies

Bruton's tyrosine kinase (BTK) is an essential component of multiple signaling pathways that regulate B cell and myeloid cell proliferation, survival, and functions, making it a promising therapeutic target for various B cell malignancies and inflammatory diseases. Five small molecule inhibitors have shown remarkable efficacy and have been approved to treat different types of hematological cancers, including ibrutinib, acalabrutinib, zanubrutinib, tirabrutinib, and orelabrutinib. The first-in-class agent, ibrutinib, has created a new era of chemotherapy-free treatment of B cell malignancies. Ibrutinib is so popular and became the fourth top-selling cancer drug worldwide in 2021. To reduce the off-target effects and overcome the acquired resistance of ibrutinib, significant efforts have been made in developing highly selective second- and third-generation BTK inhibitors and various combination approaches. Over the past few years, BTK inhibitors have also been repurposed for the treatment of inflammatory diseases. Promising data have been obtained from preclinical and early-phase clinical studies. In this review, we summarized current progress in applying BTK inhibitors in the treatment of hematological malignancies and inflammatory disorders, highlighting available results from clinical studies.

Risk of HBV reactivation in relapsed or refractory diffuse large B-cell lymphoma patients receiving Bruton tyrosine kinase inhibitors therapy

Background

Bruton tyrosine kinase inhibitors (BTKis) interrupt B-cell receptor signaling and thereby could potentially reactivate hepatitis B virus (HBV). However, data about the risk for HBV reactivation (HBVr) of BTKis in relapsed or refractory diffuse large B-cell lymphoma (R/R DLBCL) patients are sparse.

Methods

A total of 55 R/R DLBCL patients receiving BTKis therapy in the Tongji Hospital of Tongji University were enrolled. Patient clinical characteristics, treatment outcomes and details of HBVr were collected and analyzed, aiming to demonstrate the risk of HBVr in R/R DLBCL patients post BTKis therapy and the efficacy of BTKis in HBV-associated R/R DLBCL patients.

Results

Of 55 R/R DLBCL patients treated with ibrutinib (N=38) and zanubrutinib (N=17), 4 were with chronic HBV infection (HBsAg positive), 26 with resolved HBV infection (HBsAg negative and HBcAb positive) and 25 without HBV infection (HBsAg negative and HBcAb negative). In resolved HBV infection group, 2 patients developed HBVr after the use of ibrutinib and zanubrutinib respectively. Neither of them developed HBV-related hepatitis. Our finding showed that the incidence of HBVr in resolved HBV infection group was 7.69% (95% CI, 0.9-25.1%). In this study, Overall response rate (ORR) was 70.9%. 1-year overall survival (OS) rate was 80.0%. Median progression-free survival (PFS) was 4 months (95% CI, 3-5 months). In addition, HBV infection was not associated with response rates or survival among R/R DLBCL patients post BTKis treatments.

Conclusion

Our study suggested that HBV infection do not affect the efficacy of BTKis’ treatment. However, R/R DLBCL patients with resolved HBV infection are at a moderate risk of developing HBVr throughout BTKis treatment. Patients should be screened for HBVr during BTKis therapy.

Ibrutinib Plus R-ICE Induces Remission in Blastoid Variant Mantle Cell Lymphoma with CNS Relapse

Mantle cell lymphoma (MCL) is an aggressive, difficult to treat subtype of lymphoma, resulting in relapses and poor outcomes. Novel agents such as Bruton tyrosine kinase (BTK) inhibitors have been studied in the treatment of relapsed/refractory (R/R) MCL. BTK inhibitor ibrutinib, in particular, has demonstrated improvement in survival outcomes of R/R MCL. Despite these advancements, many cases of MCL, including the more aggressive blastoid and pleomorphic variants, will undergo disease progression leading to poor survival outcomes. Blastoid variant MCL is associated with an increased risk of central nervous system (CNS) involvement, causing high mortality rates. In this case report, we discuss a patient with a diagnosis of blastoid MCL with CNS relapse who achieved a complete response (CR) after receiving standard rituximab plus ifosfamide-carboplatin-etoposide (R-ICE) salvage chemotherapy with the addition of ibrutinib. The patient subsequently underwent autologous stem cell transplantation (autoSCT) and maintained CR with ibrutinib maintenance.

Ibrutinib Associated with Rituximab-Platinum Salt-Based Immunochemotherapy in B-Cell Lymphomas: Results of a Phase 1b-II Study of the LYSA Group

Simple Summary

Patients with relapsing/refractory B-cell lymphoma who respond to a platinum salt-based salvage regimen can be cured after therapy intensification followed by autologous stem cell transplantation. The Bruton tyrosine kinase inhibitor ibrutinib, given alone or in association with other molecules, has proven effective in numerous B-cell lymphomas. The aim of the current study was to evaluate the safety of the combination of ibrutinib, rituximab, dexamethasone, and cytarabine with either cisplatin (R-DHAP) or oxaliplatin (R-DHAOx), with ibrutinib given based on a prespecified dose-escalation design. The concomitant combination of ibrutinib and R-DHAP resulted in limiting hematological, infectious, and renal toxicities. As a result, the maximum ibrutinib dose could not be administered. On the other hand, when the ibrutinib administration schedule was combined with R-DHAOx, ibrutinib dosing could be increased up to the maximum prespecified dose but with relevant toxicities. Despite a strong rationale for combining ibrutinib with either R-DHAP or R-DHAP/Ox, this approach was limited by significant toxicities.

Abstract

In the post-rituximab era, patients with relapsed/refractory non-Hodgkin B-cell lymphoma (R/R B-NHL) responding to a platinum salt-based salvage regimen can potentially be cured after intensification followed by autologous stem cell transplantation, with the quality of the response to salvage predicting survival. The Bruton tyrosine kinase inhibitor ibrutinib, given as monotherapy or combined with other molecules, has proven effective in numerous B-cell lymphomas. To evaluate the safety of the combination of ibrutinib, rituximab, dexamethasone, and cytarabine with either cisplatin (R-DHAP) or oxaliplatin (R-DHAOx), we conducted a multicenter Phase 1b-II study in transplant-eligible R/R B-NHL patients, with ibrutinib given using a 3-by-3 dose-escalation design. The combination of R-DHAP and ibrutinib (given from Day 1 to Day 21 of each cycle) was associated with dose-limiting hematological, infectious, and renal toxicities, while we were unable to reach a dose to recommend for Phase II. R-DHAOx could only be combined with a daily dosage of 280 mg ibrutinib when administered continuously. R-DHAP combined with intermittent ibrutinib administration (from Day 5 to Day 18) was found to be highly toxic. On the other hand, when this administration schedule was combined with R-DHAOx, ibrutinib dosing could be increased up to 560 mg but with relevant toxicities. Despite a strong rationale for combining ibrutinib and R-DHAP/R-DHAOx, as both target lymphoma B-cells by different mechanisms, this approach was limited by significant toxicities.

Regulation of B-Cell Receptor Signaling and Its Therapeutic Relevance in Aggressive B-Cell Lymphomas

The proliferation and survival signals emanating from the B-cell receptor (BCR) constitute a crucial aspect of mature lymphocyte's life. Dysregulated BCR signaling is considered a potent contributor to tumor survival in different subtypes of B-cell non-Hodgkin lymphomas (B-NHLs). In the last decade, the emergence of BCR-associated kinases as rational therapeutic targets has led to the development and approval of several small molecule inhibitors targeting either Bruton's tyrosine kinase (BTK), spleen tyrosine kinase (SYK), or phosphatidylinositol 3 kinase (PI3K), offering alternative treatment options to standard chemoimmunotherapy, and making some of these drugs valuable assets in the anti-lymphoma armamentarium. Despite their initial effectiveness, these precision medicine strategies are limited by primary resistance in aggressive B-cell lymphoma such as diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL), especially in the case of first generation BTK inhibitors. In these patients, BCR-targeting drugs often fail to produce durable responses, and nearly all cases eventually progress with a dismal outcome, due to secondary resistance. This review will discuss our current understanding of the role of antigen-dependent and antigen-independent BCR signaling in DLBCL and MCL and will cover both approved inhibitors and investigational molecules being evaluated in early preclinical studies. We will discuss how the mechanisms of action of these molecules, and their off/on-target effects can influence their effectiveness and lead to toxicity, and how our actual knowledge supports the development of more specific inhibitors and new, rationally based, combination therapies, for the management of MCL and DLBCL patients.

Vital Hepatic Lymphoma Residuum or Excessive Immune Response? Challenging Treatment Decisions in a Patient With Systemic Lupus Erythematosus and Liver-Dominant Diffuse Large B-Cell Lymphoma: Case Report

A 28-year-old female patient with active and difficult-to-treat systemic lupus erythematosus (SLE) was diagnosed with liver-dominant diffused large B-cell lymphoma. Repeated response ¹⁸F-FDG-PET studies showed persistently high, and, despite intensified immunochemotherapy, further increasing metabolic activity of one of the hepatic lymphoma residuals, whereas all other initial lymphoma manifestations had achieved complete metabolic remission. As biopsy of the ¹⁸F-FDG-PET-positive liver residual turned out to be inconclusive, complete resection was performed. Subsequent histopathological examination, however, revealed only necrotic tissue. Thus, no further lymphoma treatment was scheduled. The patient undergoes regular surveillance and is disease-free 13 months after resection. Similarly, treatment of SLE is no longer required due to lack of activity already after the first two cycles of lymphoma treatment. The case shows how closely SLE and diffused large B-cell lymphoma can be connected and stresses the importance of interdisciplinary treatment approaches. In the future, artificial intelligence may help to further classify ¹⁸F-FDG-PET-positive lymphoma residuals. This could lead to an increase of the positive predictive value of interim- and end-of-treatment ¹⁸F-FDG-PET. The patient’s point of view enables another instructive perspective on the course of treatment, which often remains hidden to treating physicians due to lack of time in clinical routine.

Preliminary Evaluation of Zanubrutinib-Containing Regimens in DLBCL and the Cerebrospinal Fluid Distribution of Zanubrutinib: A 13-Case Series

Zanubrutinib is a second-generation Bruton’s tyrosine kinase inhibitor. Its safety and effectiveness in central nervous system (CNS) lymphoma along with its distribution in the brain and ability to cross the blood–brain barrier (BBB) remain unknown. This retrospective case series involved patients with diffuse large B-cell lymphoma (DLBCL) treated with zanubrutinib-containing regimens from August to December 2020 in PUMCH. The amounts of zanubrutinib in the plasma and brain were assessed by liquid chromatography–tandem mass spectrometry in paired plasma and cerebrospinal fluid (CSF) samples. In total, 13 patients were included: eight primary CNS lymphoma cases and five systemic DLBCL cases with 61.5% (8/13) refractory/relapsed and 84.6% (11/13) showing CNS involvement. The overall response rates were 84.5% in the entire population and 81.8% in the CNS-involved cases. A total of 23 time-matched plasma-CSF sample pairs were collected. The mean peak concentration of zanubrutinib in CSF was 2941.1 pg/ml (range, 466–9032.0 pg/ml). The corrected mean CSF/plasma ratio determined based on 94% protein binding was 42.7% ± 27.7% (range, 8.6%–106.3%). This preliminary study revealed the effectiveness of zanubrutinib-containing regimens in DLBLC, especially CNS-involved cases, for the first time. The excellent BBB penetration of zanubrutinib supports its further investigation for the treatment of CNS lymphoma.

Immune targeted therapy for diffuse large B cell lymphoma

Diffuse large B-cell lymphoma (DLBCL), the most common subtype of non-Hodgkin lymphoma, is highly heterogeneous and invasive. Although the majority of DLBCL patients show a good response to rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone treatment, approximately one-third of patients still have a poor prognosis. Many immune-targeted drugs, such as bispecific T-cell engagers and CAR T-cell therapy, have been proven effective for refractory and relapsed patients. This article reviews the progress of immune targeted therapy for DLBCL.

Primary mediastinal large B cell lymphoma

Primary mediastinal large B cell lymphoma (PMBCL) is an aggressive large B cell lymphoma originating in the mediastinum, that mainly expresses B cell surface molecules, such as CD19, CD20, CD22, andCD79a. Clinically, they are characterized by rapidly increasing anterior mediastinal masses, which can cause compression of the surrounding tissues. The diagnosis of PMBCL mainly depends on the pathological features, imaging examination and clinical features. Currently, the most commonly used therapeutic regimens are R‐CHOP and R‐EPOCH. Radiotherapy is beneficial in some patients, but it can also lead to long‐term toxicity. The research and development of novel therapies are ongoing, and some studies have achieved encouraging results, including those conducted on chimeric antigen receptor‐modified T (CAR‐T) cell therapy and anti‐PD‐1 drugs. However, randomized controlled trials with larger sample sizes are still needed. Positron emission tomography‐computed tomography (PET‐CT) is mainly used to assess the curative effect after treatment and to guide the subsequent treatment strategy.

Phase 1b/2 study of ibrutinib and lenalidomide with dose-adjusted EPOCH-R in patients with relapsed/refractory diffuse large B-cell lymphoma

Relapsed/refractory diffuse large B-cell lymphoma (DLBCL) is difficult to cure; non-germinal center B-cell-like (non-GCB) and activated B-cell-like (ABC) DLBCL have worse outcomes than GCB DLBCL. Ibrutinib and lenalidomide are synergistic in vitro in ABC DLBCL and may augment salvage chemotherapy. In part 1 of this phase 1b/2 study (NCT02142049), patients with relapsed/refractory DLBCL received ibrutinib 560 mg and escalating doses of lenalidomide on Days 1-7 with DA-EPOCH-R (Days 1-5) in 21-day cycles. In part 1 (N = 15), the maximum tolerated dose was not reached with lenalidomide 25 mg (recommended part 2 dose [RP2D]); most common grade ≥3 adverse events were anemia (73%) and febrile neutropenia (47%); the overall response rate (ORR) was 40%. At the RP2D (n = 26), ORR was 71% in non-GCB and 64% in ABC. Ibrutinib and lenalidomide with DA-EPOCH-R had a manageable safety profile and antitumor activity in relapsed/refractory DLBCL, especially the non-GCB subtype.

CD5+ diffuse large B-cell lymphoma: a narrative review

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous entity, and cell surface cluster of differentiation (CD) 5 expression may represent a distinct subset. Here, we provide a narrative review of CD5+ DLBCL to understand its clinical implications. Between 5-10% of DLBCL express CD5, making it an uncommon subset. Studies have variably shown that CD5+ DLBCL may be associated with increased age, high lactate dehydrogenase, B symptoms, extra-nodal sites, higher International Prognostic Index score, and advanced stage. CD5+ DLBCLs are more likely to express Bcl-2, MYC, and MUM1; a large proportion exhibit an activated B-cell (ABC)-like phenotype. The balance of studies generally supports an independent prognostic value of CD5 in DLBCL While more aggressive first-line regimens have been advocated for CD5+ DLBCL, including dose-adjusted R-EPOCH and autologous stem cell transplant, evidence to support these approaches is lacking; further study is warranted to identify the optimal treatment strategy for this disease entity.

Genetic Events Inhibiting Apoptosis in Diffuse Large B Cell Lymphoma

Simple Summary

Diffuse large B cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma (NHL). Despite the genetic heterogeneity of the disease, most patients are initially treated with a combination of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), but relapse occurs in ~50% of patients. One of the hallmarks of DLBCL is the occurrence of genetic events that inhibit apoptosis, which contributes to disease development and resistance to therapy. These events can affect the intrinsic or extrinsic apoptotic pathways, or their modulators. Understanding the factors that contribute to inhibition of apoptosis in DLBCL is crucial in order to be able to develop targeted therapies and improve outcomes, particularly in relapsed and refractory DLBCL (rrDLBCL). This review provides a description of the genetic events inhibiting apoptosis in DLBCL, their contribution to lymphomagenesis and chemoresistance, and their implication for the future of DLBCL therapy.

Abstract

Diffuse large B cell lymphoma (DLBCL) is curable with chemoimmunotherapy in ~65% of patients. One of the hallmarks of the pathogenesis and resistance to therapy in DLBCL is inhibition of apoptosis, which allows malignant cells to survive and acquire further alterations. Inhibition of apoptosis can be the result of genetic events inhibiting the intrinsic or extrinsic apoptotic pathways, as well as their modulators, such as the inhibitor of apoptosis proteins, P53, and components of the NF-kB pathway. Mechanisms of dysregulation include upregulation of anti-apoptotic proteins and downregulation of pro-apoptotic proteins via point mutations, amplifications, deletions, translocations, and influences of other proteins. Understanding the factors contributing to resistance to apoptosis in DLBCL is crucial in order to be able to develop targeted therapies that could improve outcomes by restoring apoptosis in malignant cells. This review describes the genetic events inhibiting apoptosis in DLBCL, provides a perspective of their interactions in lymphomagenesis, and discusses their implication for the future of DLBCL therapy.

Identification BCL6 and miR-30 family associating with Ibrutinib resistance in activated B-cell-like diffuse large B-cell lymphoma

Ibrutinib has clear efficacy for activated B-cell-like diffuse large B cell lymphoma (ABC-DLBCL) in previous clinical researches. However, the resistance of Ibrutinib has limited its therapeutic benefit and the potential mechanism remains unclear. This study was aimed to identify potential candidate genes and miRNA targets to overcome Ibrutinib resistance in ABC-DLBCL. First, two expression profiles were downloaded from the GEO database, which used to identify the DEGs related to Ibrutinib resistance in ABC-DLBCL cell lines by GEO2R analysis separately. And the common DEGs were obtained though Venn diagram. Then Gene ontology (GO) and pathway enrichment analysis were conducted by DAVID database. From STRING database, BCL6, IL10, IL2RB, IRF4, CD80, PRDM1and GZMB were determined to be the hub genes by protein-protein interaction (PPI) network. Through miRNA-mRNA targeting network, we found that BCL6, IRF4, CD80, and PRDM1 were common target genes of miR-30 family. The cBioPortal database showed that BCL6 had the highest level of genetic alterations among DLBCL. In addition, another expression profile from GEO database showed that BCL6 was significantly high expression in no responsive patients after Ibrutinib treatment, and the receiver operating characteristic (ROC) curve which was used to evaluate the relationship between BCL6 expression and its effect was 0.67. MTT assay showed that treatment with FX1 (a BCL6 inhibitor) can enhance the sensitivity of Ibrutinib in C481S BTK HBL-1 cells. The results suggested that BCL6 and miR-30 family maybe associate with Ibrutinib resistance in ABC-DLBCL.

New agents and regimens for diffuse large B cell lymphoma

As a widely recognized standard regimen, R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) is able to cure two-thirds patients with diffuse large B cell lymphoma (DLBCL), and the remaining patients suffer from refractory or relapsed disease due to resistance to R-CHOP and fare poorly. Unsatisfied outcomes for those relapsed/refractory patients prompted efforts to discover new treatment approaches for DLBCL, including chimeric antigen receptor T cells, bispecific T cell engagers, immunomodulatory drugs, immune checkpoint inhibitors, monoclonal antibodies, antibody-drug conjugates, molecular pathway inhibitors, and epigenetic-modifying drugs. Herein, up-to-date data about the most promising treatment approaches for DLBCL are recapitulated, and novel genetic classification systems are introduced to guide individualized treatment for DLBCL.

PIM Kinases Promote Survival and Immune Escape in Primary Mediastinal Large B-Cell Lymphoma through Modulation of JAK-STAT and NF-κB Activity

Primary mediastinal large B-cell lymphoma (PMBL) cells depend on the constitutive activity of NF-κB and STAT transcription factors, which drive expression of multiple molecules essential for their survival. In a molecularly related B-cell malignant tumor (classic Hodgkin lymphoma), tumor Reed-Sternberg cells overexpress oncogenic (proviral integration site for Moloney murine leukemia virus (PIM) 1, 2, and 3 kinases in a NF-κB- and STAT-dependent manner and PIMs enhance survival and expression of immunomodulatory molecules. Given the multiple overlapping characteristics of Reed-Sternberg and PMBL cells, we hypothesized that PIM kinases may be overexpressed in PMBL and involved in PMBL pathogenesis. The expression of PIM kinases in PMBL diagnostic biopsy specimens was assessed and their role in survival and immune escape of the tumor cells was determined. PIMs were abundantly expressed in primary tumors and PMBL cell lines. Inhibition of PIM kinases was toxic to PMBL cells, attenuated protein translation, and down-regulated NF-κB- and STAT-dependent transcription of prosurvival factors BCL2A1, BCL2L1, and FCER2. Furthermore, PIM inhibition decreased expression of molecules engaged in shaping the immunosuppressive microenvironment, including programmed death ligand 1/2 and chemokine (C-C motif) ligand 17. Taken together, our data indicate that PIMs support PMBL cell survival and immune escape and identify PIMs as promising therapeutic targets for PMBL.

Inhibitors targeting Bruton's tyrosine kinase in cancers: drug development advances

Bruton’s tyrosine kinase (BTK) inhibitor is a promising novel agent that has potential efficiency in B-cell malignancies. It took approximately 20 years from target discovery to new drug approval. The first-in-class drug ibrutinib creates possibilities for an era of chemotherapy-free management of B-cell malignancies, and it is so popular that gross sales have rapidly grown to more than 230 billion dollars in just 6 years, with annual sales exceeding 80 billion dollars; it also became one of the five top-selling medicines in the world. Numerous clinical trials of BTK inhibitors in cancers were initiated in the last decade, and ~73 trials were intensively announced or updated with extended follow-up data in the most recent 3 years. In this review, we summarized the significant milestones in the preclinical discovery and clinical development of BTK inhibitors to better understand the clinical and commercial potential as well as the directions being taken. Furthermore, it also contributes impactful lessons regarding the discovery and development of other novel therapies.

Ibrutinib in B-cell lymphoma: single fighter might be enough?

Background

In recent years, the B cell receptor (BCR) signaling pathway has become a "hot point" because it plays a critical role in B-cell proliferation and function. Bruton's tyrosine kinase (BTK) is overexpressed in many subtypes of B-cell lymphoma as a downstream kinase in the BCR signaling pathway. Ibrutinib, the first generation of BTK inhibitor, has shown excellent antitumor activity in both indolent and aggressive B-cell lymphoma.

Main body

Ibrutinib monotherapy has been confirmed to be effective with a high response rate (RR) and well-tolerated in many B-cell lymphoma subgroups. To achieve much deeper and faster remission, combination strategies contained ibrutinib were conducted to evaluate their synergistic anti-tumor effect.

Conclusions

For patients with indolent B-cell lymphoma, most of them respond well with ibrutinib monotherapy. Combination strategies contained ibrutinib might be a better choice to achieve deeper and faster remission in the treatment of aggressive subtypes of B-cell lymphoma. Further investigations on the long-term efficacy and safety of the ibrutinib will provide novel strategies for individualized treatment of B-cell lymphoma.

CircCFL1/MiR-107 Axis Targeting HMGB1 Promotes the Malignant Progression of Diffuse Large B-Cell Lymphoma Tumors

Objective

The pathogenesis of diffuse large B-cell lymphoma (DLBCL) has not yet been fully elucidated. An increasing number of studies have shown that circular RNAs (circRNAs) play an important role in tumorigenesis and development. The aim of this study was to investigate the effect of CircCFL1 on the malignant progression of DLBCL.

Methods

RT-qPCR was used to detect the expression levels of CircCFL1 and miR-107. A dual-luciferase reporter gene experiment was conducted to verify that CircCFL1 targeted miR-107 and the miR-107 target gene HMGB1. BrdU, transwell, and MTT tests were performed to detect cell invasion and proliferation. Western blot analysis was used to detect the phosphorylation of proteins. Xenograft models were established to confirm the effect of CircCFL1 on DLBCL tumor growth in vivo.

Results

The expression of CircCFL1 in cells transfected with the CircCFL1 overexpression vector was higher than that in the control group. After overexpressing CircCFL1, the expression of miR-107 in cells decreased significantly, and the protein level of HMGB1 increased. The dual-luciferase reporter gene experiment showed that CircCFL1 directly bound to miR-107 and reduced the inhibition of the target gene HMGB1. After CircCFL1 was overexpressed, cell migration and proliferation were enhanced. The tumor volume and weight in the lentivirus CircCFL1 group were higher than those in the lentivirus NC group.

Conclusion

Results showed that the circRNA CircCFL1 could regulate the expression of HMGB1 through miR-107 to promote the proliferation and migration of DLBCL.

An evaluation of polatuzumab vedotin for the treatment of patients with diffuse large B-cell lymphoma

INTRODUCTION

Diffuse Large B-Cell lymphoma (DLBCL) is the most commonly diagnosed form of non-Hodgkin lymphoma (NHL) in adults. Most patients receive an initial treatment with chemo-immunotherapy, which includes rituximab, cyclophosphamide, vincristine, doxorubicin and prednisone (R-CHOP). Cure rates are high but those who relapse, or do not respond to initial therapy, have a poor prognosis. Polatuzumab vedotin, an anti-CD79b monoclonal antibody conjugated to the cytotoxic payload monomethyl aurostatin-E (MMAE), in combination with bendamustine and rituximab (polatuzumab-BR) is a new, effective therapeutic option to add to the treatment of relapsed/refractory (R/R) DLBCL.

AREAS COVERED

This review covers the clinical development of polatuzumab for the treatment of lymphoma, its current and future use in patients with DLBCL and identifies its place in the treatment of R/R DLBCL. A search of PubMed and oncology/hematology congresses using 'polatuzumab' as the search term was undertaken to identify the most pertinent clinical reports.

EXPERT OPINION

Polatuzumab-BR is an effective and safe option for transplant-ineligible patients with R/R DLBCL either before or after CAR-T (chimeric antigen receptor T-cell therapy). Ongoing combination trials with polatuzumab will expand its applications in the treatment of this disease.

Infection profiles of different chemotherapy regimens and the clinical feasibility of antimicrobial prophylaxis in patients with DLBCL

Various chemotherapy regimens are used to treat patients with diffuse large B-cell lymphoma (DLBCL). However, treatment-related toxicity with a focus on infectious disease has not been fully reviewed. Several phase 3 trials have demonstrated different rates of febrile neutropenia (FN) between regimens (e.g. dose-adjusted (DA) EPOCH-R vs. R-CHOP). With heterogeneous patient characteristics, a combination regimen of lenalidomide or ibrutinib with R-CHOP exhibited promising efficacy with moderate infectious toxicity. While R-bendamustine is feasible for patients who don't tolerate other forms of chemotherapy, clinical data indicate increased opportunistic infections under prolonged lymphopenia. The usefulness of prophylactic antibiotics/antifungal agents in DLBCL patients is controversial owing to shorter and less severe neutropenia than with the induction regimen for acute leukemia or hematopoietic stem-cell transplantation. Prophylactic granulocyte-colony stimulating factor is recommended for intensive regimens such as DA-EPOCH-R, R-DHAP, or R-ICE. Regardless of multiple studies about FN incidence, studies focusing on microbiologic events are limited, and further investigations are warranted.

Polatuzumab vedotin for the treatment of adults with relapsed or refractory diffuse large B-cell lymphoma

INTRODUCTION

Polatuzumab vedotin is an antibody-drug conjugate comprised of an anti-CD79b monoclonal antibody conjugated to monomethyl auristatin (MMAE), a microtubule-disrupting cytotoxin. CD79b is almost exclusively expressed on normal and malignant B-cells, making it an appealing target for novel therapeutics.

AREAS COVERED

This article reviews the current literature on polatuzumab vedotin, including its pharmacology, as well as summarizing the results of clinical trials in relapsed/refractory diffuse large B-cell lymphoma (DLBCL) as a single agent and in combination with other chemotherapies and chemoimmunotherapies. The current landscape of approved therapies for relapsed and refractory DLBCL, as well as other promising novel approaches, is discussed.

EXPERT OPINION

The recent approval of polatuzumab vedotin in combination with bendamustine and rituximab (BR) offers another option to patients with DLBCL who are not eligible for autologous hematopoietic cell transplant or chimeric antigen receptors (CAR)-T cell therapy. In younger patients and those without serious comorbidities, polatuzumab vedotin-BR may serve as bridging therapy to more intensive therapies with reasonable efficacy and tolerability. Polatuzumab vedotin is currently being studied in a randomized trial in the front line setting in combination with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP).

Treatment of relapsed/refractory paediatric aggressive B-cell non-Hodgkin lymphoma

Aggressive B-cell non-Hodgkin lymphoma (B-NHL) accounts for ≈60% of NHL in children/adolescents. In newly diagnosed Burkitt lymphoma and diffuse large B-cell lymphoma, short intensive multiagent chemotherapy is associated with a five-year event-free survival of around 90%. Very few children/adolescents with aggressive B-NHL show a relapsed/refractory (r/r) disease. The outcome is poor, with cure rates <30%, and there is no standard of care. Rituximab-containing salvage regimens may provide a complete/partial response in 60-70% of cases. However, long-term survival is <10% for non-transplanted patients. Autologous or allogeneic haematopoietic stem cell transplant is, nowadays, the best option for responding patients, with survival rates around 50%. The benefit of autologous versus allogeneic HSCT is not clear. Numerous novel therapies for r/r B-NHL are currently being tested in adults, including next-generation monoclonal antibodies, novel cellular therapy strategies and therapies directed against new targets. Some are under investigation also in children/adolescents, with promising preliminary results.

Apigenin and Abivertinib, a novel BTK inhibitor synergize to inhibit diffuse large B-cell lymphoma in vivo and vitro

Background: Apigenin, a flavonoid phytochemical extracted from fruits and vegetables, has shown anti-neoplastic effects in a variety of malignant tumors. DLBCL is the most common type of aggressive lymphoma in adults with a poor prognosis. Small-molecule inhibitors like BTK inhibitors have demonstrated extended period of disease control. Whereas the effects of the synergetic inhibition of the two have not been elucidated.

Methods: We assessed the efficacy of Apigenin alone or combined with Abivertinib to inhibit DLBCL progression. Cell viability was examined using the cell proliferation cell proliferation assay (MTS). Apoptotic cells and cell cycle evaluation were detected by Annexin V-FITC and DNA staining solution respectively. Western blot was used to explore the potential mechanism, and the in vivo effects of the two drugs were performed by a DLBCL xenograft BALB/c nude mice model.

Results: Our results demonstrated that Apigenin can inhibit the proliferation and clone forming of DLBCL cells. Apigenin also induces apoptosis by down-regulating BCL-XL and activating Caspase family. In addition, Apigenin down-regulates cell cycle proteins including CDK2/CDK4/CDK6/CDC2/p-RB to increase G2/M phase arrest. Mechanically, our data demonstrate that Apigenin leads to a significant reduction of the expression of pro-proliferative pathway PI3K/mTOR to inhibit DLBCL cells survival. Moreover, our in vitro and in vivo results show that Apigenin can synergize with Abivertinib, a novel BTK inhibitor, in treating DLBCL visa synergistically inducing apoptosis and inhibiting the p-GS3K-β and its downstream targets.

Conclusions: Collectively, our study suggests that Apigenin exerts improving anti-lymphoma effect of BTK inhibitors and provides hope to targeted therapy of those develop resistance.

The Role of Autologous Stem Cell Transplantation in the Treatment of Diffuse Large B-cell Lymphoma in the Era of CAR-T Cell Therapy

For many years now and based on the results of the PARMA trial, relapsed Diffuse Large B-cell Lymphoma (DLBCL) is treated with salvage combination cytotoxic chemotherapy (most often platinum-based) followed by high dose myeloablative chemotherapy and autologous stem cell transplantation (auto-HCT). This approach has resulted in long-term disease free survival in about half of the patients. With the incorporation of rituximab in the upfront treatment (RCHOP), more patients with DLBCL are cured but there has been a signal of inferior outcomes with auto-HCT if DLBCL relapses. Nevertheless, a careful review of the literature still shows very good outcomes with auto-HCT for DLBCL with complete remission to salvage chemotherapy. For those who do not respond well to classic salvage other approaches are reviewed here including chimeric antigen receptor (CAR) T-cell therapy and treatment with antibody-drug conjugates (ADCs) as well as bispecific T-cell engagers (BiTEs). The outcome of auto-HCT after successful treatment with ADCs or BITEs is unknown. It is also unknown if CAR-T cell therapy should be reserved for those who have failed 2 lines of chemotherapy or it should be moved earlier. Finally, we review here the effects of Myc and bcl2 amplifications or translocations to the outcome of the auto-HCT. Some attempts to improve the salvage or conditioning regimens are mentioned. We also discuss the role of allogeneic stem cell transplantation (allo-HCT) in the paradigm of treatment for relapsed DLBCL.

Genetic alterations and their clinical implications in DLBCL

Diffuse large B cell lymphoma (DLBCL) is a highly heterogeneous lymphoid neoplasm with variations in gene expression profiles and genetic alterations, which lead to substantial variations in clinical course and response to therapy. The advent of high-throughput genome sequencing platforms, and especially whole-exome sequencing, has helped to define the genetic landscape of DLBCL. In the past 10 years, these studies have identified many genetic alterations in DLBCL, some of which are specific to B cell lymphomas, whereas others can also be observed in other types of cancer. These aberrations result in altered activation of a wide range of signalling pathways and other cellular processes, including those involved in B cell differentiation, B cell receptor signalling, activation of the NF-κB pathway, apoptosis and epigenetic regulation. Further elaboration of the genetics of DLBCL will not only improve our understanding of disease pathogenesis but also provide further insight into disease classification, prognostication and therapeutic targets. In this Review, we describe the current understanding of the prevalence and causes of specific genetic alterations in DLBCL and their role in disease development and progression. We also summarize the available clinical data on therapies designed to target the aberrant pathways driven by these alterations.

Hematopoietic-cell transplantation for lymphoma in the era of genetically engineered cellular therapy: it's not quite time to scrap the old vehicle for the new car

PURPOSE OF REVIEW

Second-line platinum-based salvage chemotherapy followed by high-dose chemotherapy and autologous hematopoietic-cell transplantation (AHCT) has remained the standard of care (SOC) for relapsed and primary refractory (r/r) diffuse large B-cell lymphoma (DLBCL) for greater than 2 decades. In the postrituximab era, this strategy has yielded disappointing outcomes for r/r patients with curability in less one-quarter of the patients by intention-to-treat.

RECENT FINDINGS

Given the Food and Drug Administration (FDA) approval of chimeric antigen receptor (CAR) modified T cells directed against CD19 (CD19 CAR T) for DLBCL following two lines of therapy and/or failed AHCT, encouragement with this therapy in the second line for r/r patients has naturally prompted randomized phase III studies against the aforementioned SOC. The predominant hurdle to procession to AHCT is chemotherapy sensitivity after platinum-based salvage therapy.

SUMMARY

In this review, we will discuss recent investigations to improve response rates in r/r DLBCL with the intent of proceeding to potentially curative AHCT, as well as investigations to decrease progression post-AHCT. In addition, data regarding currently FDA approved CD19 CAR T cells will be reviewed. Within 2-3 years, we will know if the multicenter/multinational studies of CD19 CAR T will replace SOC salvage therapy and AHCT in the second-line. The role of allogeneic HCT will also be briefly reviewed in the context of these therapies.

Diffuse large B-cell lymphoma: 2019 update on diagnosis, risk stratification, and treatment

DISEASE OVERVIEW

Diffuse large B-cell lymphoma (DLBCL) is the most common type of aggressive non-Hodgkin lymphoma originating from the germinal center, and it represents a heterogeneous group of diseases with variable outcomes that are differentially characterized by clinical features, cell of origin (COO), molecular features, and most recently, frequently recurring mutations.

DIAGNOSIS

DLBCL is ideally diagnosed from an excisional biopsy of a suspicious lymph node, which shows sheets of large cells that disrupt the underlying structural integrity of the follicle center and stain positive for pan-B-cell antigens, such as CD20 and CD79a. COO is determined by immunohistochemical stains, while molecular features such as double-hit or triple-hit disease are determined by fluorescent in situ hybridization analysis. Commercial tests for frequently recurring mutations are currently not routinely used to inform treatment.

RISK STRATIFICATION

Clinical prognostic systems for DLBCL, including the rituximab International Prognostic Index, age-adjusted IPI, and NCCN-IPI, use clinical factors for the risk stratification of patients, although this does not affect the treatment approach. Furthermore, DLBCL patients with non-germinal center B-cell (GCB)-like DLBCL (activated B-cell like and unclassifiable) have a poorer response to up-front chemoimmunotherapy (CI) compared to patients with GCB-like DLBCL. Those with c-MYC-altered disease alone and in combination with translocations in BCL2 and/or BCL6 (particularly when the MYC translocation partner is immunoglobulin) respond poorly to up-front CI and salvage autologous stem cell transplant at relapse.

RISK-ADAPTED THERAPY

This review will focus on differential treatment of DLBCL up-front and at the time of relapse by COO and molecular features.

Biology and therapy of primary mediastinal B-cell lymphoma: current status and future directions

Primary mediastinal B-cell lymphoma (PMBCL) is a distinct disease closely related to classical nodular sclerosing Hodgkin lymphoma. Conventional diagnostic paradigms utilising clinical, morphological and immunophenotypical features can be challenging due to overlapping features with other B-cell lymphomas. Reliable diagnostic and prognostic biomarkers that are applicable to the conventional diagnostic laboratory are largely lacking. Nuclear factor kappa B (NF-κB) and Janus kinase/signal transducers and activators of transcription (JAK-STAT) signalling pathways are characteristically dysregulated in PMBCL and implicated in several aspects of disease pathogenesis, and the latter pathway in host immune evasion. The tumour microenvironment is manipulated by PMBCL tumours to avoid T-cell mediated destruction via strategies that include loss of tumour cell antigenicity, T-cell exhaustion and activation of suppressive T-regulatory cells. R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone) and DA-EPOCH-R (dose-adjusted etoposide, prednisolone, vincristine, cyclophosphamide, doxorubicin, rituximab) are the most common first-line immunochemotherapy regimens. End of treatment positron emission tomography scans are the recommended imaging modality and are being evaluated to stratify patients for radiotherapy. Relapsed/refractory disease has a relatively poor outcome despite salvage immunochemotherapy and subsequent autologous stem cell transplantation. Novel therapies are therefore being developed for treatment-resistant disease, targeting aberrant cellular signalling and immune evasion.

Dysregulation of Cell Survival in Diffuse Large B Cell Lymphoma: Mechanisms and Therapeutic Targets

Diffuse large B cell lymphoma (DLBCL) is the most common type of lymphoma worldwide, representing 30-40% of non-Hodgkin lymphomas, and is clinically aggressive. Although more than half of patients with DLBCL are cured by using standard first-line immunochemotherapy, the remaining patients are refractory to the first-line therapy or relapse after complete remission and these patients require novel therapeutic approaches. Understanding the pathogenesis of DLBCL is essential for identifying therapeutic targets to tackle this disease. Cell survival dysregulation, a hallmark of cancer, is a characteristic feature of DLBCL. Intrinsic signaling aberrations, tumor microenvironment dysfunction, and viral factors can all contribute to the cell survival dysregulation in DLBCL. In recent years, several novel drugs that target abnormal cell survival pathways, have been developed and tested in clinical trials of patients with DLBCL. In this review, we discuss cell survival dysregulation, the underlying mechanisms, and how to target abnormal cell survival therapeutically in DLBCL patients.

Epidemiology, outcome, targeted agents and immunotherapy in adolescent and young adult non-Hodgkin and Hodgkin lymphoma

The epidemiology, outcome and targeted immunotherapy in adolescent and young adult non-Hodgkin and Hodgkin lymphoma were discussed during the 6th International Symposium on Childhood, Adolescent and Young Adult Non-Hodgkin Lymphoma September 26th-29th 2018 in Rotterdam, the Netherlands. This review summarizes some of those presentations, as well as other current and novel antibody therapy, immune check-point inhibitors, chimeric antigen receptor T cells, cancer vaccines and cytotoxic T lymphocyte therapy.

Mature B-NHL in children, adolescents and young adults: current therapeutic approach and emerging treatment strategies

Mature B cell lymphomas account for approximately 60% of all cases of non-Hodgkin lymphoma (NHL) in children and adolescents and includes Burkitt lymphoma (BL), diffuse large B cell lymphoma (DLBCL) and other less common histologies. The outcome for patients treated with modern regimens in resource-intensive settings is excellent. Improvements in care have been accomplished through enhanced supportive therapy, including tumour lysis management and incremental refinement of chemotherapy backbones via cooperative group clinical trials in which patients receive risk group-specific intensive chemotherapy. More recent trials have established the safety and efficacy of immunotherapy. Ongoing work is required to address the substantial burden of acute therapy-related toxicity, as well as the identification of effective therapies for those patients with relapsed and refractory disease, for whom outcomes remain very poor. In this review we will summarize the results from recent therapeutic clinical trials, describe the evidence to support the inclusion of rituximab and review the rationale for the investigation of several new categories of novel agents for mature B cell lymphomas in children and adolescents.

How I manage patients with relapsed/refractory diffuse large B cell lymphoma

Despite progress in the upfront treatment of diffuse large B cell lymphoma (DLBCL), patients still experience relapses. Salvage chemotherapy followed by autologous stem cell transplantation (ASCT) is the standard second‐line treatment for relapsed and refractory (R/R) DLBCL. However, half of the patients will not be eligible for transplantation due to ineffective salvage treatment, and the other half will relapse after ASCT. In randomized studies, no salvage chemotherapy regimen is superior to another. The outcomes are affected by the secondary International Prognostic Index at relapse and various biological factors. The strategy is less clear in patients who require third‐line treatment. A multicohort retrospective non‐Hodgkin lymphoma research (SCHOLAR‐1) study conducted in 636 patients with refractory DLBCL showed an objective response rate of 26% (complete response 7%) to the next line of therapy with a median overall survival of 6·3 months. In the case of a response followed by transplantation, long‐term survival can be achieved in DLBCL patients. There is clearly a need for new drugs that improve salvage efficacy. Encouraging results have been reported with chimeric antigen receptor ‐T cell engineering, warranting further studies in a well‐defined control group of refractory patients. The Collaborative Trial in Relapsed Aggressive Lymphoma (CORAL) was used as a handy framework to build the discussion.