Autologous or reduced-intensity conditioning allogeneic hematopoietic cell transplantation for chemotherapy-sensitive mantle-cell lymphoma: analysis of transplantation timing and modality

Dismantling relapsed/refractory mantle cell lymphoma

Despite recent therapeutic advancements in the general field of non-Hodgkin lymphoma, effective treatment of relapsed or refractory (R/R) mantle cell lymphoma (MCL) remains a challenge. The development of Bruton tyrosine kinase (BTK) inhibitors has revolutionized the field and these agents are now the mainstay of R/R MCL management. However, BTK inhibitors are not curative, and as they are increasingly being incorporated into frontline regimens, the shifting treatment landscape for R/R disease presents new challenges. Here we review data for commonly employed treatment strategies including BTK inhibitors, the BCL2-inhibitor venetoclax, lenalidomide-based regimens, and chimeric antigen receptor T-cell therapy. We additionally review data for promising novel agents including antibody-drug conjugates and bispecific antibodies before highlighting some emerging targeted agents that continue to bring promise for improved outcomes in R/R MCL.

Age barriers in allogeneic hematopoietic cell transplantation: Raising the silver curtain

Allogeneic hematopoietic cell transplantation (HCT) is no longer exclusively for the young. With an aging population, development of non-intensive remission-inducing strategies for hematologic malignancies, and novel graft-versus-host disease-prevention platforms, an older population of patients is pursuing HCT. The evolving population of HCT recipients requires an overhaul in the way we risk-stratify and optimize patients prior to HCT. Here, we review the history and current state of HCT for older adults and propose an assessment and intervention flow to bridge the gaps in today's clinical guidelines.

Allogeneic stem cell transplantation and CAR-T in B-cell Non-Hodgkin Lymphoma: a two-center experience and review of the literature

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is still a potentially curative option for B-cell Non-Hodgkin Lymphoma (B-NHL) in the modern immunotherapy era. The objective of this study was to analyze long-term outcomes of patients with B-NHL who received allo-HSCT. We analyzed overall survival (OS), progression-free survival (PFS) and graft versus host disease (GVHD) relapse-free survival (GRFS) in 53 patients undergoing allo-HSCT from two institutions. The median follow-up of the study was 72 months (range 29-115 months). The median number of lines of therapy before allo-HSCT was 3 (range 1-6) and twenty-eight patients (53%) had received a previous autologous transplant. The 3-year PFS, OS and GRFS were 55%, 63%, and 55%, respectively. One-year non-relapse mortality was 26%. Karnofsky Performance Scale < 90 was associated with worse OS in multivariable analysis. A non-comparative analysis of a cohort of 44 patients with similar characteristics who received chimeric antigen receptor T-cell therapy was done, showing a 1-year PFS and OS were 60% and 66%, respectively. Our data shows that allo-HSCT is still a useful option for treating selected patients with R/R B-NHL. Our retrospective analysis and review of the literature demonstrate that allo-HSCT can provide durable remissions in a subset of patients with R/R B-NHL.

Fatal outcome of BK virus encephalitis in an allogeneic stem cell transplantation recipient

BK virus (BKV) encephalitis is a rare complication after hematopoietic stem cell transplantation (HSCT). A 43-year-old woman with recurrent follicular lymphoma after autologous HSCT received allogeneic bone marrow transplantation from a human leukocyte antigen-matched related donor. Neutrophil engraftment was achieved on post-transplant day 13. Memory loss and noncooperative attitude toward the medical staff were observed on day 16, and her mental status worsened progressively. Magnetic resonance imaging (MRI) showed nonspecific findings on day 19; however, cerebrospinal fluid (CSF) analysis including real-time polymerase chain reaction on day 20 revealed elevated levels of BKV 4.67 × 104 copy/mL. BKV encephalitis was diagnosed based on CSF findings, intravenous administration of immunoglobulin and cidofovir was started, and the immunosuppressive agent dose was reduced. Diffusion-weighted MRI on day 28 showed signal abnormalities in the bilateral periventricular white matter. Although the follow-up CSF analysis on day 35 was negative for BKV, her mental status and MRI findings did not improve, and she died on day 55 because of respiratory failure. This case emphasizes the importance of considering BKV encephalitis as a differential diagnosis of post-transplant encephalitis, considering the central nervous system-associated immune reconstitution inflammatory syndrome in patients with worsening central nervous system findings after eradication of BKV in the CSF.

Recent advances in genomics and therapeutics in mantle cell lymphoma

Over the past decades, significant strides have been made in understanding the pathobiology, prognosis, and treatment options for mantle cell lymphoma (MCL). The heterogeneity observed in MCL's biology, genomics, and clinical manifestations, including indolent and aggressive forms, is intricately linked to factors such as the mutational status of the variable region of the immunoglobulin heavy chain gene, epigenetic profiling, and Sox11 expression. Several intriguing subtypes of MCL, such as Cyclin D1-negative MCL, in situ mantle cell neoplasm, CCND1/IGH FISH-negative MCL, and the impact of karyotypic complexity on prognosis, have been explored. Notably, recent immunochemotherapy regimens have yielded long-lasting remissions in select patients. The therapeutic landscape for MCL is continuously evolving, with a shift towards nonchemotherapeutic agents like ibrutinib, acalabrutinib, and venetoclax. The introduction of BTK inhibitors has brought about a transformative change in MCL treatment. Nevertheless, the challenge of resistance to BTK inhibitors persists, prompting ongoing efforts to discover strategies for overcoming this resistance. These strategies encompass non-covalent BTK inhibitors, immunomodulatory agents, BCL2 inhibitors, and CAR-T cell therapy, either as standalone treatments or in combination regimens. Furthermore, developing novel drugs holds promise for further improving the survival of patients with relapsed or refractory MCL. In this comprehensive review, we methodically encapsulate MCL's clinical and pathological attributes and the factors influencing prognosis. We also undertake an in-depth examination of stratified treatment alternatives. We investigate conceivable resistance mechanisms in MCL from a genetic standpoint and offer precise insights into various therapeutic approaches for relapsed or refractory MCL.

Do CAR-T and Allogeneic Stem Cell Transplant Both Have a Place in Lymphoid Neoplasms?

Allogeneic stem cell transplantation (allo-SCT) represented the first immunotherapy to treat hematologic malignancies: it has been considered as a cure for the disease and never as an approach to extend the life of patients. The success of allo-SCT derives both from the ability to treat patients with intensive chemoradiotherapy and from the potent graft-versus-leukemia effects mediated by donor immunity. Although considerable progress has been made in the last years, significant barriers still remain in the form of disease relapse, graft-versus-host disease, infectious complications, and regimen-related toxicities. Moreover, the treatment of hematologic malignancies, particularly acute lymphoblastic leukemia and certain forms of lymphomas, has been revolutionized by the commercial introduction of genetically modified autologous T-lymphocyte therapy (CAR-T). Our review discusses current standards and the shifting paradigms in the indications for allo-SCT and the role of CAR-T cell therapy for lymphoid neoplasms.

What is the role of up-front autologous stem cell transplantation in mantle cell lymphoma?

Up-front autologous stem cell transplantation (ASCT) is the established standard of care for younger, transplant-eligible MCL patients and is associated with a prolonged progression-free survival (PFS) benefit. However, there is no randomized controlled trial data, with therapy including rituximab and cytarabine, that has established a PFS and overall survival (OS) benefit with ASCT in the modern era. Multiple retrospective studies have failed to identify an OS benefit associated with ASCT in younger MCL patients. The high-risk patient subgroup with evidence of baseline TP53 mutation has a dismal outcome with intensive chemoimmunotherapy followed by ASCT, thus up-front ASCT is not optimal for this patient subset. Ongoing randomized clinical trials will help to clarify the role of up-front ASCT in the future. For example, the ongoing European MCL Network Triangle study incorporating ibrutinib into chemoimmunotherapy induction and maintenance with and without ASCT will help define the role of ASCT in the era of novel biologically targeted agents (ClinicalTrials.gov identifier: NCT02858258). Additionally, minimal residual disease (MRD) assessment is a powerful prognostic tool in MCL, and the ongoing Eastern Cooperative Oncology Group-American College of Radiology Imaging Network E4151 study is comparing maintenance rituximab alone vs ASCT consolidation in MCL patients who achieve remission and MRD-undetectable status post induction (ClinicalTrials.gov identifier: NCT03267433). ASCT remains a highly efficacious initial therapy for younger MCL patients; however, ultimately the decision to pursue ASCT requires discussion of risks vs benefits, incorporating patient preferences and values.

The place of allogeneic stem cell transplantation in aggressive B-cell non-Hodgkin lymphoma in the era of CAR-T-cell therapy

Chimeric antigen receptor T (CAR-T) cells are a treatment option for patients with relapse/refractory (R/R) non-Hodgkin lymphoma (NHL), acute lymphoid leukemia and multiple myeloma. To date, diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL), follicular lymphoma (FL), and chronic lymphocytic leukemia (CLL) have been successfully treated with CAR-T cells directed against the CD19 antigen. However, when R/R disease persists after several treatment lines, patients with these diseases are often referred to transplantation centres to receive allogeneic stem cell transplantation (ALLO-SCT). ALLO-SCT and CAR-T cells share mechanism of actions, inducing immune effects of T-cells (and other cells after transplantation) against lymphoma cells, but they differ in several other characteristics. These differences justify unique positioning of each therapy within treatment algorithms. In this paper, we analyzed the results obtained after ALLO-SCT and CAR-T-cell therapy in patients with aggressive lymphomas (large B-cell lymphoma and MCL) to identify the ideal scenarios in which these 2 immunological therapies should be employed.

Allogeneic hematopoietic stem cell transplantation in non-Hodgkin lymphoma in Switzerland, 30 years of experience: Sooner is better

Due to relatively high nonrelapse mortality (NRM), allogeneic hematopoietic stem cell transplantation (allo-HSCT) in non-Hodgkin's lymphoma (NHL) remains the ultimate line of treatment but the only curable approach in a setting of relapse/refractory disease. Here, we conducted a retrospective, multicenter, registry-based analysis on patients who underwent allo-HSCT for NHL in Switzerland, over 30-year (1985-2020) period. The study included 301 allo-HSCTs performed for NHL patients in three University Hospitals of Switzerland (Zurich, Basel and Geneva) 09/1985 to 05/2020. We assessed in univariate and multivariable analysis the impact on survivals (overall survival [OS], relapse free survival [RFS], relapse incidence [RI], and non-treatment related mortality [NRM]). The maximum follow-up was 25 years with median follow-up for alive patients of 61 months. The median age at allo-HSCT was 51 years. Three- and -year OS was - 59.5% and 55.4%; 3- and 5-year PFS was 50% and 44%; 3- and 5-year NRM was 21.7% and 23.6%. RI at 3 and 5 years was 27.4% and 34.9%. In conclusion, our analysis of the entire Swiss experience of allo-HSCT in patients with NHL shows promising 5- and possibly 10-year OS and relatively acceptable NRM rates for such population, the majority being not in complete remission (CR) at the time of transplantation.

Mantle Cell Lymphoma: the Role of Risk-Adapted Therapy and Treatment of Relapsed Disease

PURPOSE OF REVIEW

In this review, the current treatment strategies are recapped, evolving agents are discussed, and we provide guidance in treating R/R MCL.

RECENT FINDINGS

There has been an advancement in treatment using targeted therapy, cellular therapies including chimeric antigen receptor (CAR) T cell therapy and hematopoietic stem cell transplantation (HSCT) and novel therapeutic agents including non-covalent BTKis, bispecific antibodies, and antibody-drug conjugates for treatment of refractory and relapsed mantle cell lymphoma. Mantle cell lymphoma (MCL) is a mature B-cell lymphoma that is associated with a poor prognosis. Current treatments include immunochemotherapy, chemotherapy and autologous stem cell transplantation (SCT) which place patients in remission but result in relapse. Chemoimmunotherapy uses chemotherapeutic agents paired with rituximab in patients who have chemo-sensitive disease with prolonged remission of at least > 2 years and/or have contraindications to chemotherapy that serve as bridges to more definitive treatment. Additional therapies including proteosome inhibitor-based therapies and immunomodulators, like bortezomib and lenalidomide, can be used as single agents or in combination with others. Bruton's tyrosine kinase (BTK) inhibitors including ibrutinib, acalaburtinib, and zanubrutinib have also been proven effective for the treatment of (R/R) disease. Another agent is Venetoclax, a robust drug that can be used in MCL after progression or intolerance to BTKi. Newer advances in the management of MCL have led to the utilization of cellular therapies including chimeric antigen receptor (CAR) T cell therapy and SCT that are options for healthy young (< 65 years old) who have progressed through several lines of therapies. With progression of disease, mutations are acquired that cause therapy resistance. Novel therapeutic agents such as non-covalent BTKis, bispecific antibodies, and antibody-drug conjugates are paving the way for advancements in treatment for R/R MCL. R/R MCL is a complex disease with many therapeutic options none of which has been proven superior in head-to-head comparison. In this review, the current treatment strategies are recapped, evolving agents are discussed, and we provide guidance in treating R/R MCL.

Stem cell transplant for mantle cell lymphoma in Taiwan

Mantle cell lymphoma (MCL) is a B-cell lymphoma featuring an aggressive course and a progressive relapsing pattern. International guidelines recommend early consolidative autologous stem cell transplant (auto-SCT) for eligible patients while reserving allogeneic SCT (allo-SCT) as therapy for refractory cases. Since data describing the implementation of transplants in the Asian population with MCL are limited, we aimed to analyze post-SCT outcomes of 99 MCL patients from the Taiwan Bone Marrow Transplant Registry database. The median age was 56 years, and 11% of the patients had blastoid variant MCL. Ninety-four patients received auto-SCT, while 13 patients received allo-SCT, eight of which received allo-SCT after failing auto-SCT. Before auto-SCT, 52% of the patients were in their first complete remission (CR1). Overall, 37 patients (39%) relapsed after auto-SCT. The median post-auto-SCT progression-free survival and overall survival (OS) were 43.6 months and not reached, respectively. Blastoid variant MCL, transplant not received in CR1, and disease progression within 12 months post-auto-SCT independently predicted inferior OS in multivariable analysis. The median post-allo-SCT OS was 74 months. Two patients (15%) died of MCL recurrence post-allo-SCT. Three patients with refractory diseases were salvaged with ibrutinib or venetoclax to allo-SCT. Treatment strategies incorporating novel agents warrant further optimization.

Use of BTK inhibitors with focus on ibrutinib in mantle cell lymphoma: an expert panel opinion statement

The introduction of BTK inhibitors transformed the management of patients with mantle cell lymphoma (MCL). Ibrutinib, the first-in-class BTK inhibitor is now approved in more than 80 countries and there are over 20 new BTK inhibitors in development. In addition, novel agents show potential clinical activity (alone and in combination) and are in the approval phase and/or being studied in ongoing clinical trials. How does the practicing clinician decide on the optimal therapeutic strategy for this highly heterogenous disease? In July 2020 a group of experts from Italy, convened a meeting to address and provide clarification on a series of outstanding issues in the treatment of MCL with the view of providing clinical guidance on its management. This expert opinion statement represents the panel's collective analysis, evaluation, and recommendations and is made up of a series of questions and answers (in the form of a review of the pertinent literature) designed to replicate those posed by practicing clinicians in Italy but which are applicable to clinical settings worldwide. This article is protected by copyright. All rights reserved.

Mantle cell lymphoma management trends and novel agents: where are we going?

The heterogeneity in disease pathology, the unpredictability in disease prognosis, and the variability in response to therapy make mantle cell lymphoma (MCL) a focus of novel therapeutic development. MCL is characterized by dysregulated expression of cyclin D1 through a chromosome t(11;14) translocation. MCL international prognostic index (MIPI), ki-67 proliferation index, and TP53 mutation status are currently utilized for prognostication. With advances in pharmacokinetic analysis and drug discovery, treatment strategy has evolved from chemotherapy to combination of targeted, epigenetic, and immune therapies. In this review, we discuss investigational and newly approved treatment approaches. In a short time, the US Food and Drug Administration (FDA) has approved five agents for the treatment of MCL: lenalidomide, an immunomodulatory agent; bortezomib, a proteasome inhibitor; and ibrutinib, acalabrutinib, and zanubrutinib, all Bruton kinase inhibitors. Epigenetic agents (e.g. cladribine and vorinostat), mammalian target of rapamycin (mTOR) inhibitors (e.g. temsirolimus and everolimus), and monoclonal antibodies and/or antibody-drug conjugates (e.g. obinutuzumab, polatuzumab, and ublituximab) are promising therapeutic agents currently under clinical trial investigation. Most recently, chimeric antigen receptor (CAR)-T cell therapy and bispecific T-cell engager (BiTE) therapy even open a new venue for MCL treatment. However, due to its intricate pathology nature and high relapse incidence, there are still unmet needs in developing optimal therapeutic strategies for both frontline and relapsed/refractory settings. The ultimate goal is to develop innovative personalized combination therapy approaches for the purpose of delivering precision medicine to cure this disease.

Outcomes and Utilization Trends of Front-Line Autologous Hematopoietic Cell Transplantation for Mantle Cell Lymphoma

Although autologous hematopoietic cell transplantation (auto-HCT) has become a common practice for eligible patients in the front-line setting with mantle cell lymphoma (MCL), there are limited data regarding trends in auto-HCT utilization and associated outcomes. This study used the Center for International Blood and Marrow Transplant Research (CIBMTR) database to evaluate survival outcomes and auto-HCT utilization in adults age ≥18 years who underwent auto-HCT within 12 months of diagnosis of MCL between January 2000 and December 2018. The 19-year period from 2000 to 2018 was divided into 4 separate intervals-2000 to 2004, 2005 to 2009, 2010 to 2014, and 2015 to 2018-and encompassed 5082 patients. To evaluate transplantation utilization patterns, we combined MCL incidence derived from the SEER 21 database with CIBMTR- reported auto-HCT activity within 12 months of diagnosis of MCL. Primary outcomes included overall survival (OS) along with the auto-HCT utilization rate. The cumulative incidence of nonrelapse mortality at 1 year decreased from 7% in the earliest cohort (2000 to 2004) to 2% in the latest cohort (2015 to 2018). Mirroring this trend, OS outcomes improved continually with time, with a 3-year OS of 72% in the earliest cohort improving to 86% in the latest cohort. In addition, we noted an increase in auto-HCT utilization from 2001 to 2018, particularly in patients age ≤65 years. This large retrospective analysis highlights trends in auto-HCT utilization and outcomes in patients with MCL and emphasizes the need to optimize pretransplantation and post-transplantation treatment strategies to enhance survival outcomes.

Effect of time to relapse on overall survival in patients with mantle cell lymphoma following autologous haematopoietic cell transplantation

In young and fit patients with mantle cell lymphoma (MCL), intensive induction therapy followed by a consolidative autologous haematopoietic cell transplant (autoHCT) is the standard of care in the front-line setting. Recently, time-to-event analysis has emerged as an important risk assessment tool in lymphoma, though its impact in MCL is not well defined. We utilized the Center for International Blood and Marrow Transplant Research database to evaluate the effect of post-autoHCT time to relapse on overall survival (OS) over time in 461 patients who underwent autoHCT within 12 months of MCL diagnosis. On multivariate analysis, the impact of relapse on OS was greatest at the six-month [hazard ratio (HR) = 7·68], 12-month (HR = 6·68), and 18-month (HR = 5·81) landmark timepoints. Using a dynamic landmark model we demonstrate that adjusted OS at five years following each landmark timepoint improved with time for relapsing and non-relapsing patients. Furthermore, early relapse (<18 months) following autoHCT defines a high-risk group with inferior post-relapse OS. This retrospective analysis highlights the impact of time to relapse on OS in MCL patients undergoing up-front autoHCT and emphasizes the need to consider novel therapeutic approaches for patients suffering early relapse.

American Society of Transplantation and Cellular Therapy, Center of International Blood and Marrow Transplant Research, and European Society for Blood and Marrow Transplantation Clinical Practice Recommendations for Transplantation and Cellular Therapies in Mantle Cell Lymphoma

Autologous (auto-) and allogeneic (allo-) hematopoietic cell transplantation (HCT) are accepted treatment modalities in contemporary treatment algorithms for mantle cell lymphoma (MCL). Chimeric antigen receptor (CAR) T cell therapy recently received approval for MCL; however, its exact place and sequence in relation to HCT remain unclear. The American Society of Transplantation and Cellular Therapy, Center of International Blood and Marrow Transplant Research, and the European Society for Blood and Marrow Transplantation jointly convened an expert panel to formulate consensus recommendations for role, timing, and sequencing of auto-HCT, allo-HCT, and CAR T cell therapy for patients with newly diagnosed and relapsed/refractory (R/R) MCL. The RAND-modified Delphi method was used to generate consensus statements. Seventeen consensus statements were generated, with a few key statements as follows: in the first line setting, auto-HCT consolidation represents standard of care in eligible patients, whereas there is no clear role of allo-HCT or CAR T cell therapy outside of clinical trials. In the R/R setting, the preferential option is CAR T cell therapy, especially in patients with MCL failing or intolerant to at least one Bruton's tyrosine kinase inhibitor, while allo-HCT is recommended if CAR T cell therapy fails or is infeasible. Several recommendations were based on expert opinion, where the panel developed consensus statements for important real-world clinical scenarios to guide clinical practice. In the absence of contemporary evidence-based data, the panel found RAND-modified Delphi methodology effective in providing a formal framework for developing consensus recommendations for the timing and sequence of cellular therapies for MCL.

ASTCT, CIBMTR, and EBMT clinical practice recommendations for transplant and cellular therapies in mantle cell lymphoma

Autologous (auto-) or allogeneic (allo-) hematopoietic cell transplantation (HCT) are accepted treatment modalities for mantle cell lymphoma (MCL). Recently, chimeric antigen receptor (CAR) T-cell therapy received approval for MCL; however, its exact place and sequence in relation to HCT is unclear. The ASTCT, CIBMTR, and the EBMT, jointly convened an expert panel to formulate consensus recommendations for role, timing, and sequencing of auto-, allo-HCT, and CAR T-cell therapy for patients with newly diagnosed and relapsed/refractory (R/R) MCL. The RAND-modified Delphi method was used to generate consensus statements. Seventeen consensus statements were generated; in the first-line setting auto-HCT consolidation represents standard-of-care in eligible patients, whereas there is no clear role of allo-HCT or CAR T-cell therapy, outside of a clinical trial. In the R/R setting, the preferential option is CAR T-cell therapy especially in MCL failing or intolerant to at least one Bruton's tyrosine kinase inhibitor, while allo-HCT is recommended if CAR T-cell therapy has failed or is not feasible. In the absence of contemporary evidence-based data, the panel found RAND-modified Delphi methodology effective in providing a formal framework for developing consensus recommendations for the timing and sequence of cellular therapies for MCL.

R-MACLO-IVAM regimen followed by maintenance therapy induces durable remissions in untreated mantle cell lymphoma - Long term follow up results

We present long-term combined results of two clinical trials implementing R-MACLO-IVAM induction followed by thalidomide or rituximab maintenance in 44 patients with untreated mantle cell lymphoma (MCL). The first 22 patients (UM-MCL1 ClinicalTrials.gov identifier NCT00450801) received maintenance with thalidomide (200 mg daily until relapse/intolerable toxicity) and a subsequent cohort of 22 patients (UM-MCL2 ClinicalTrials.gov identifier NCT00878254) received rituximab (375 mg/m² IV weekly × 4, repeated every 6 months for 3 years). Considering all 44 patients, 41 (93.2%) achieved complete response (CR), two (4.5%) partial response (PR), and one (2.3%) was not evaluated for response. With a median follow up of 7.2 years (range < 1 month to 16 years), the 5-year progression-free survival (PFS) was 55.6% (95% CI: 38.9%-69.4%) and median PFS 7.9 years (95% CI: 3.7-11 years). The 5-year OS was 83.3% (95% CI: 68.1%-91.7%) and median OS was not reached. Patients with blastic variant (n = 6) had a 5-year PFS and OS of 20.8% and 60%, respectively. Myelosuppression was the most common adverse event during immunochemotherapy. Long-term treatment-related mortality was 6.8%. Note, R-MACLO-IVAM followed by maintenance therapy is an effective regimen to induce long-term remission in MCL without need for consolidation with ASCT.

Autologous tumor cell vaccine induces antitumor T cell immune responses in patients with mantle cell lymphoma: A phase I/II trial

Here, we report on the results of a phase I/II trial (NCT00490529) for patients with mantle cell lymphoma who, having achieved remission after immunochemotherapy, were vaccinated with irradiated, CpG-activated tumor cells. Subsequently, vaccine-primed lymphocytes were collected and reinfused after a standard autologous stem cell transplantation (ASCT). The primary endpoint was detection of minimal residual disease (MRD) within 1 yr after ASCT at the previously validated threshold of ≥1 malignant cell per 10,000 leukocyte equivalents. Of 45 evaluable patients, 40 (89%) were found to be MRD negative, and the MRD-positive patients experienced early subsequent relapse. The vaccination induced antitumor CD8 T cell immune responses in 40% of patients, and these were associated with favorable clinical outcomes. Patients with high tumor PD-L1 expression after in vitro exposure to CpG had inferior outcomes. Vaccination with CpG-stimulated autologous tumor cells followed by the adoptive transfer of vaccine-primed lymphocytes after ASCT is feasible and safe.

Cellular Therapies for Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is a subtype of B cell non-Hodgkin lymphoma characterized by a heterogeneous clinical presentation. Patients who demonstrate an objective response to induction therapy(ies) and are eligible for intensive therapies are offered an autologous hematopoietic cell transplant (HCT) as front-line consolidation followed by rituximab maintenance. Allogeneic HCT is an option for younger and fit patients with high-risk disease or in patients who have relapsed after autologous HCT. Recent advances in T cell engineering brought chimeric antigen receptor T cell (CAR T) therapy from the bench to the bedside, with brexucabtagene autoleucel being the first CAR T product approved by the US Food and Drug Administration for use in relapsed/refractory MCL. In this comprehensive review, we summarize the literature on available cellular therapies for MCL and present a treatment algorithm that incorporates HCT, autologous or allogeneic, and CAR T therapies.

Allogeneic Stem Cell Transplantation in Mantle Cell Lymphoma in the Era of New Drugs and CAR-T Cell Therapy

MCL is an uncommon lymphoproliferative disorder that has been regarded as incurable since its identification as a distinct entity. Allogeneic transplantation for two decades has represented the only option capable of ensuring prolonged remissions and possibly cure. Despite its efficacy, its application has been limited by feasibility limitations and substantial toxicity, particularly in elderly patients. Nevertheless, the experience accumulated over time has been wide though often scattered among retrospective and small prospective studies. In this review, we aimed at critically revise and discuss available evidence on allogeneic transplantation in MCL, trying to put available evidence into the 2020 perspective, characterized by unprecedented development of novel promising therapeutic agents and regimens.

Cost-effectiveness for KTE-X19 CAR T therapy for adult patients with relapsed/refractory mantle cell lymphoma in the United States

AIMS

The objective of this study is to estimate the cost-effectiveness of KTE-X19 versus standard of care (SoC) in the treatment of relapsed/refractory (R/R) mantle cell lymphoma (MCL) patients from a US healthcare perspective.

MATERIALS AND METHODS

A three-state partitioned-survival model (pre-progression, post-progression, and death) with a cycle length of 1 month was used to extrapolate progression-free and overall survival (OS) over a lifetime horizon. Due to the long tail of the OS curve, OS was modeled applying a mixture-cure methodology, using the assumption that patients whose disease had not progressed after 5 years experienced long-term remission. Population inputs were derived from the ZUMA-2 trial. This was also the source of KTE-X19 efficacy and safety data, while this data was obtained from the literature for SoC. Costs and resource use inputs were derived from the published literature and publicly available data sources. Health state utilities were derived from the ZUMA-2 trial (NCT02601313), applying the US tariff. Adverse event disutilities were derived from the published literature. Costs and health outcomes were discounted at 3% per year. The model estimated expected life years (LY), quality-adjusted life years (QALY), and total costs for KTE-X19 vs SoC. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS

Median survival was 9.71 years for KTE-X19 and 2.13 for SoC. Discounted LYs, QALYs, and lifetime costs were 8.99, 7.39, and $693,832 for KTE-X19 vs 4.47, 3.65, and $574,263 for SoC, respectively. The KTE-X19 vs SoC cost per QALY was $31,985. The most influential model parameter was the utility for patients with long-term remission. At a willingness-to-pay threshold of $150,000 per QALY, the probability that KTE-X19 was cost-effective was 99%.

CONCLUSION

The treatment of R/R MCL with KTE-X19 presents a potentially cost-effective alternative to the current SoC, deriving its value from incremental survival and health-related quality-of-life benefits.

Hematopoeitic Cell Transplantation and CAR T-Cell Therapy: Complements or Competitors?

Allogeneic hematopoietic cell transplantation (allo-HCT) and chimeric antigen receptor T cell (CAR T) therapy are the main modalities of adoptive cellular immunotherapy that have widely permeated the clinical space. The advent of both technologies revolutionized treatment of many hematologic malignancies, both offering the chance at sustained remissions for patients who would otherwise invariably succumb to their diseases. The understanding and exploitation of the nonspecific alloreactivity of allo-HCT and the graft-versus-tumor effect is contrasted by the genetically engineered precision of CAR T therapy. Historically, those with relapsed and refractory hematologic malignancies have often been considered for allo-HCT, although outcomes vary dramatically and are associated with potential acute and chronic toxicities. Such patients, mainly with B-lymphoid malignancies, may now be offered CAR T therapy. Yet, a lack of prospective data to guide decisions thereafter requires individualized approaches on whether to proceed to allo-HCT or observe. The continued innovations to make CAR T therapy more effective and accessible will continue to alter such approaches, but similar innovations in allo-HCT will likely result in similarly improved clinical outcomes. In this review, we describe the history of the two platforms, dissect the clinical indications emphasizing their intertwining and competitive roles described in trials and practice guidelines, and highlight innovations in which they complement or inform one another.

Outcomes in first relapsed-refractory younger patients with mantle cell lymphoma: results from the MANTLE-FIRST study

Patients with mantle cell lymphoma (MCL) that fail induction treatment represent a difficult-to-treat population, where no standard therapy exists. We evaluated outcomes in patients with first relapsed-refractory (r/r) MCL after upfront high dose cytarabine including standard regimens. Overall survival (OS-2) and progression-free survival (PFS-2) were estimated from the time of salvage therapy. The previously described threshold of 24 months was used to define patients as early- or late-progressors (POD). Overall, 261 r/r MCL patients were included. Second-line regimens consisted of rituximab-bendamustine (R-B, 21%), R-B and cytarabine (R-BAC, 29%), ibrutinib (19%), and others (31%). The four groups were balanced in terms of clinicopathological features. Adjusting for age and early/late-POD, patients treated with R-BAC had significantly higher complete remission (63%) than comparators. Overall, Ibrutinib and R-BAC were associated with improved median PFS-2 [24 and 25 months, respectively], compared to R-B (13) or others (7). In patients with early-POD (n = 127), ibrutinib was associated with inferior risk of death than comparators (HR 2.41 for R-B, 2.17 for others, 2.78 for R-BAC). In patients with late-POD (n = 134), no significant differences were observed between ibrutinib and bendamustine-based treatments. Ibrutinib was associated with improved outcome in early-POD patients.

Key Clinical and Translational Research Questions to Address Unmet Needs in Mantle Cell Lymphoma

Survival for patients with mantle cell lymphoma has improved dramatically over the last 2 decades owing to a better understanding of disease biology and the development of more effective treatment regimens for patients with untreated and relapsed disease. With these advancements, we are now poised to ask questions that challenge old treatment strategies, use new technologies, and improve our understanding of disease heterogeneity. This article focuses on questions that we believe will drive the future of mantle cell lymphoma treatment. Although not an exhaustive list, we review current literature, ongoing studies, and provide expert opinion on future trial design.

Initial and Consolidation Therapy for Younger Patients with Mantle Cell Lymphoma

Mantle cell lymphoma is an incurable B-cell malignancy. Treatment of young fit patients is particularly challenging, because careful consideration should be made when building a long-term treatment strategy that would provide longer remissions and increase patients' quality of life. Most young fit patients achieve long remissions with a combination of immunochemotherapy containing rituximab and high-dose cytarabine, followed by high-dose chemotherapy and autologous stem-cell transplantation. The addition of maintenance therapy with rituximab following autologous stem-cell transplantation prolongs the time to relapse and increases overall survival. Despite an intensive approach, late relapses are common and are usually treated with novel agents.

Allogeneic Transplantation and Chimeric Antigen Receptor-Engineered T-Cell Therapy for Relapsed or Refractory Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) accounts for fewer than 10% of non-Hodgkin lymphoma. There is a high initial response rate to chemotherapy and rituximab, but a nearly universal risk of relapse. Allogeneic hematopoietic cell transplantation (allo-HCT) provides one of the only curative options. We review the role of allo-HCT for relapsed and refractory (R/R) MCL and discuss a novel promising approach using autologous chimeric antigen receptor-engineered T (CAR-T) cells. We review preliminary safety and efficacy data of 2 pivotal trials investigating the use of CD19-targeted CAR-T cells for R/R MCL after ibrutinib failure and discuss potential timing of these approaches.

Evaluating the Therapeutic Potential of Zanubrutinib in the Treatment of Relapsed/Refractory Mantle Cell Lymphoma: Evidence to Date

Mantle cell lymphoma (MCL) is an uncommon B-cell non-Hodgkin lymphoma characterized by an aggressive clinical course in the majority of patients. Despite recent improvements in outcomes, MCL remains incurable and a major therapeutic challenge. BTK inhibitors are the preferred treatment option for patients with relapsed/refractory MCL, including those unfit for chemotherapy or those with chemoresistant disease. In addition to ibrutinib and acalabrutinib, the FDA recently approved zanubrutinib for the treatment of patients with relapsed/refractory MCL based on the results of two Phase 2 clinical trials showing overall response rates of 85–87% with complete responses in 30–77% of patients. Compared with ibrutinib, zanubrutinib is more selective for BTK and has less off-target inhibition, which is thought to limit certain toxicities although direct comparative data are still lacking. This review article summarizes data from clinical trials of currently FDA-approved BTK inhibitors in MCL with a focus on zanubrutinib.

Mantle cell lymphoma

MCL is a well-characterized generally aggressive lymphoma with a poor prognosis. However, patients with a more indolent disease have been reported in whom the initiation of therapy can be delayed without any consequence for the survival. In 2017 the World Health Organization updated the classification of MCL describing two main subtypes with specific molecular characteristics and clinical features, classical and indolent leukaemic nonnodal MCL. Recent research results suggested an improving outcome of this neoplasm. The addition of rituximab to conventional chemotherapy has increased overall response rates, but it did not improve overall survival compared to chemotherapy alone. The use of intensive frontline therapies including rituximab and consolidation with autologous stem cell transplantation ameliorated response rate and prolonged progression-free survival in young fit patients, but any impact on survival remains to be proven. Furthermore, the optimal timing, cytoreductive regimen and conditioning regimen, and the clinical implications of achieving a disease remission even at molecular level remain to be elucidated. The development of targeted therapies as the consequence of better understanding of pathogenetic pathways in MCL might improve the outcome of conventional chemotherapy and spare the toxicity of intense therapy in most patients. Cases not eligible for intensive regimens, may be considered for less demanding therapies, such as the combination of rituximab either with CHOP or with purine analogues, or bendamustine. Allogeneic SCT can be an effective option for relapsed disease in patients who are fit enough and have a compatible donor. Maintenance rituximab may be considered after response to immunochemotherapy as the first-line strategy in a wide range of patients. Finally, since the optimal approach to the management of MCL is still evolving, it is critical that these patients are enrolled in clinical trials to identify the better treatment options.

Correlative analysis of overall survival with clinical characteristics in 127 patients with mantle cell lymphoma: a multi-institutional cohort in Taiwan

Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma often with extranodal involvement at diagnosis, and yet how this feature correlates with survival awaits elucidation. To address this issue, a correlative analysis between clinical features of 127 MCL patients and their overall survival (OS) was conducted. In this cohort, the median age at MCL diagnosis was 62 years and 81% were males. Eighty-four percent of patients were Ann Arbor stage 4, and 15% were blastoid variants. In patients with gastrointestinal MCL, approximately 40% had gastric involvement. In treatment, CHOP-based induction chemotherapy was given to 61.1% of patients. One-third of patients undertook autologous stem cell transplant (SCT), and 4.7% had allogeneic SCT. The median OS was 82 months and well-stratified in MIPI risk groups. In the multivariate analysis for OS, blastoid variants and gastric involvement were both independent risk factors whereas auto-SCT had a protective effect. Overall, this study corroborated with the current understandings and international therapeutic standards for MCL. Auto-SCT associated with a better OS while allo-SCT remained an option for blastoid variants and those who failed Auto-SCT. Interestingly, patients with gastric involvement tended to have worse survival, a finding that spawns more studies to investigate the mechanism.

Front-line management of indolent non-Hodgkin lymphoma in Australia. Part 2: mantle cell lymphoma and marginal zone lymphoma

Mantle cell lymphoma (MCL) and the marginal zone lymphoma (MZL) subtypes (nodal MZL, extra-nodal MZL of mucosa-associated lymphoid tissue (MALT lymphoma) and splenic MZL) are uncommon lymphoma subtypes, accounting for less than 5-10% of all non-Hodgkin lymphoma. The evidence base for therapy is therefore limited and enrolment into clinical trials is preferred. Outcomes for patients with MCL have been steadily improving mainly due to the adoption of more intense strategies in younger patients, the use of rituximab maintenance and the recent introduction of bendamustine in older patients. MZL is a more heterogeneous group of cancer with both nodal, extra-nodal and splenic subtypes. Extranodal MZL may be associated with autoimmune or infectious aetiologies, and can respond to eradication of the causative pathogen. Proton pump inhibitor plus dual antibiotics in Helicobacter pylori positive gastric MALT lymphoma is curative in many patients. Watchful waiting is appropriate in most patients with asymptomatic advanced stage disease, which tends to behave in a particularly indolent manner. Other options for symptomatic disease include splenectomy, chemoimmunotherapy with rituximab and, more recently, targeted therapies.

Allogeneic transplantation in elderly patients ≥65 years with non-Hodgkin lymphoma: a time-trend analysis

Allogeneic hematopoietic cell transplantation (allo-HCT) is a curative therapy for relapsed/refractory and high-risk non-Hodgkin lymphoma (NHL). However, no large studies have evaluated allo-HCT utilization in elderly NHL patients (≥65 years). Using the CIBMTR registry, we report a time-trend analysis of 727 NHL patients (≥65 years) undergoing the first allo-HCT from 2000 to 2015 in the United States (US). Study cohorts were divided by time period: 2000-2005 (N = 76) vs. 2006-2010 (N = 238) vs. 2011-2015 (N = 413). Primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), relapse/progression (R/P), and non-relapse mortality (NRM). Median age at transplant, use of reduced-intensity conditioning, and graft source remained stable, while use of unrelated donors increased in the most current era. The 1-year probabilities of NRM from 2000 to 2005 vs. 2006-2010 vs. 2011-2015 were 24% vs. 19% vs. 21%, respectively (p = 0.67). Four-year probability of R/P was similar among the three cohorts: 48% (2000-2005), 40% (2006-2010), and 40% (2011-2015) (p = 0.39). The 4-year probabilities of PFS and OS (2000-2005 vs. 2006-2010 vs. 2011-2015) showed significantly improved outcomes in more recent time periods: 17% vs. 31% vs. 30% (p = 0.02) and 21% vs. 42% vs. 44% (p < 0.001), respectively. Utilization of allo-HCT increased in elderly NHL patients in the US since 2000 with improving survival outcomes.

Optimal management of mantle cell lymphoma in the primary setting

Introduction: The management of mantle cell lymphoma (MCL) has significantly improved since the use of intensified induction and autologous stem cell transplant consolidation. Evolving developments in minimal residual disease detection and novel agent therapy are now challenging this frontline treatment paradigm. Areas covered: This review discusses both the established role of induction and transplant consolidation in MCL, followed by evolving concepts in the use of novel agents in the frontline setting, and the use of minimal residual disease as a driver of MCL management. Expert opinion: In an era of novel agents and improved biologic understanding of MCL, our goal for frontline management should evolve toward personalized therapy for individual patients to maximize efficacy and survival whilst minimizing treatment-related toxicities.

Is It Time to Revisit the Role of Allogeneic Transplantation in Lymphoma?

PURPOSE OF REVIEW

A multitude of new drug and cell therapy approvals for lymphoma has prompted questions about the role of allogeneic blood or marrow transplantation (allo-BMT). We sought to review the latest evidence examining the role of allo-BMT for lymphoma in this evolving landscape.

RECENT FINDINGS

Despite several new drug classes, there remains a large unmet need, particularly in hard to treat subtypes of lymphoma and for patients with relapsed/refractory disease. Allo-BMT can provide an opportunity for cure due to a potent graft vs lymphoma effect in high-risk relapse/refractory follicular lymphoma, mantle cell lymphoma, and aggressive T cell lymphomas. Chimeric antigen receptor T cell therapy and checkpoint blockers have improved outcomes for patients with relapsed /aggressive B cell lymphomas and Hodgkin lymphoma respectively; the role of allo-BMT consolidation in the treatment algorithm for responders to these therapies is an evolving topic. Expanded donor availability including haploidentical relatives has improved access to allo-BMT. Non-myeloablative conditioning regimens and post-transplant cyclophosphamide prophylaxis have improved early transplant-related morbidity and rates of graft versus host disease and translated into long-term survival for patients with lymphoid malignancies. Patient selection remains key, but allo-BMT remains the only modality able to deliver durable long-term remissions across different types of lymphoma.

Patterns of survival in patients with recurrent mantle cell lymphoma in the modern era: progressive shortening in response duration and survival after each relapse

As the survival of patients with mantle cell lymphoma (MCL) continues to improve, patients are increasingly being treated with multiple regimens. However, outcome after each line remains poorly characterized in the modern era. To address this knowledge gap, we retrospectively studied 404 consecutive MCL patients who were managed between 2000 and 2014 at Memorial Sloan Kettering Cancer Center. Histologic diagnosis was centrally confirmed, and patients were followed longitudinally from diagnosis throughout their disease course. Progression-free survival (PFS) and overall survival (OS) were determined by Kaplan–Meier method. The median OS and PFS after first-line treatment were 9.7 and 4.0 years, respectively. After second-line therapy, the median OS and PFS were 41.1 and 14.0 months, third line were 25.2 and 6.5 months, and fourth line were 14.4 and 5.0 months. In patients less than 65 years, stem cell transplant (SCT)-based frontline regimens were associated with improved PFS compared with non-SCT regimens (median PFS: 86.2 versus 40.0 months; P < 0.01), with a trend toward longer OS (median OS: 165.0 versus 120.0 months; P = 0.06). Early treatment failure after first-line regimens was associated with worse OS (5.9 versus 2.5 years; P < 0.01). Our study should facilitate establishing proper endpoints for future clinical trials using novel treatment approaches.

Indications for haematopoietic stem cell transplantation for haematological diseases, solid tumours and immune disorders: current practice in Europe, 2019

This is the seventh special EBMT report on the indications for haematopoietic stem cell transplantation for haematological diseases, solid tumours and immune disorders. Our aim is to provide general guidance on transplant indications according to prevailing clinical practice in EBMT countries and centres. In order to inform patient decisions, these recommendations must be considered together with the risk of the disease, the risk of the transplant procedure and the results of non-transplant strategies. In over two decades since the first report, the EBMT indications manuscripts have incorporated changes in transplant practice coming from scientific and technical developments in the field. In this same period, the establishment of JACIE accreditation has promoted high quality and led to improved outcomes of patient and donor care and laboratory performance in transplantation and cellular therapy. An updated report with operating definitions, revised indications and an additional set of data with overall survival at 1 year and non-relapse mortality at day 100 after transplant in the commonest standard-of-care indications is presented. Additional efforts are currently underway to enable EBMT member centres to benchmark their risk-adapted outcomes as part of the Registry upgrade Project 2020 against national and/or international outcome data.

Recent advances and future directions in mantle cell lymphoma research: report of the 2018 mantle cell lymphoma consortium workshop

Mantle cell lymphoma (MCL) is an aggressive B-cell non-Hodgkin lymphoma characterized by the t(11;14) chromosomal translocation. This translocation most often results in overexpression of cyclin D1. MCL is clinically heterogeneous, outcomes are generally poor, and no standard treatment has been established. The recent approvals of ibrutinib and acalabrutinib have provided an additional therapeutic option; however, resistance has emerged as a significant issue and presents the need for more detailed studies of resistance mechanisms. Recent clinical trials have provided new perspectives on the relative efficacy and safety of various approaches for both transplant-eligible and transplant-ineligible patients. Multiple novel strategies are being evaluated in the treatment of MCL, including both targeted agents and cellular immunotherapies. At the Lymphoma Research Foundation's 13th MCL Workshop, researchers gathered to discuss research findings, clinical trial results, and future directions related to MCL, its biology, and its treatment. This report, which includes a summary of each presentation, aims to review recent findings in MCL research and highlight potential areas for future study.

Strategies to improve outcomes of autologous hematopoietic cell transplant in lymphoma

High-dose chemotherapy and autologous hematopoietic cell transplantation (HDT-AHCT) remains an effective therapy in lymphoma. Over the past several decades, HDT with BEAM (carmustine, etoposide, cytarabine, and melphalan) and CBV (cyclophosphamide, carmustine, and etoposide) have been the most frequently used preparatory regimens for AHCT in Hodgkin (HL) and non-Hodgkin lymphoma (NHL). This article reviews alternative combination conditioning regimens, as well as novel transplant strategies that have been developed, to reduce transplant-related toxicity while maintaining or improving efficacy. These data demonstrate that incorporation of maintenance therapy posttransplant might be the best way to improve outcomes.

Advances in Transplantation for Lymphomas Resulting from CIBMTR Lymphoma Working Committee's Research Portfolio: A Five-Year Report (2013-2018)

The Center for International Blood and Marrow Transplant Research (CIBMTR) is a research collaboration between the National Marrow Donor Program (NMDP)/Be The Match and the Medical College of Wisconsin (MCW). The CIBMTR collaborates with the global scientific community to advance hematopoietic cell transplantation (HCT) and cellular therapy worldwide to increase survival and enrich quality of life for patients. The observation research program within CIBMTR is organized into 15 working committees. This review is aiming to highlight the observational research studies published by the CIBMTR Lymphoma Working committee over the last five years (2013-18) and to summarize how these studies have impacted the field by helping inform clinical practice in scenarios where prospective data from high quality randomized trials were not available or where owing to the rarity of a particular transplant indication such data were unlikely to be generated, outside the setting of a large observational research database. The salient findings reviewed include; (a) studies supporting role of autologous HCT in diffuse large B-cell lymphoma (DLBCL) patients with sensitive relapse of disease within one year of diagnosis, (b) role of autologous HCT vs allogeneic HCT in follicular lymphoma patients with early therapy failure, (c) prognostic scoring system development for classical Hodgkin lymphoma and DLBCL patients with prior autograft failure, (d) defining the role of alternative donor transplantation in lymphomas, (e) evaluating appropriate conditioning regimens for HCT in lymphoma, and (f) outcomes of HCT in rare lymphoid malignancies.

The Impact of Advanced Patient Age on Mortality after Allogeneic Hematopoietic Cell Transplantation for Non-Hodgkin Lymphoma: A Retrospective Study by the European Society for Blood and Marrow Transplantation Lymphoma Working Party

More than 60% of patients with non-Hodgkin lymphoma (NHL) are age >60 years at presentation. The purpose of this study was to compare the potential risks and benefits of allogeneic hematopoietic cell transplantation (alloHCT) in elderly patients with NHL with younger patients in a large sample, also taking into account comorbidity information. All patients age ≥18 years who had undergone alloHCT from a matched sibling or unrelated donor for NHL between 2003 and 2013 and were registered with the European Society for Blood and Marrow Transplantation were eligible for the study. The primary study endpoint was 1-year nonrelapse mortality (NRM). A total of 3919 patients were eligible and were categorized by age: young (Y), 18 to 50 y (n = 1772); middle age (MA), 51 to 65 y (n = 1967); or old (O), 66 to 77 y (n = 180). Follicular lymphoma was present in 37% of the patients; diffuse large B cell lymphoma, in 30%; mantle cell lymphoma, in 21%, and peripheral T cell lymphoma, in 11%. At the time of alloHCT, 85% of the patients were chemosensitive and 15% were chemorefractory. With a median follow-up of 4.5 years in survivors, NRM at 1 year was 13% for the Y group. 20% for the MA group, and 33% for the O group (P <.001), whereas relapse incidence and overall survival (OS) at 3 years in the 3 groups were 30%, 31%, and 28% (P = .355) and 60%, 54%, and 38% (P <.001), respectively. Multivariable adjustment for confounders, including sex, NHL subset, time from diagnosis, chemosensitivity, donor, and conditioning, confirmed older age as a significant predictor for NRM and OS, but not for relapse risk. Although comorbidity was a significant predictor of NRM in a subset analysis restricted to the 979 patients with comorbidity information available, age retained its significant impact on NRM. In conclusion, our data show that alloHCT in patients age >65 y provides similar NHL control as seen in younger patients but is associated with a higher NRM that is not fully explained by comorbidity. Thus, although alloHCT is feasible and effective in very old patients, the increased NRM risk must be taken into account when assessing the indication for alloHCT for NHL in this age group.

Evolving treatment strategies in mantle cell lymphoma

Mantle cell lymphoma is an incurable, moderately aggressive B cell lymphoma. While a small proportion of patients with indolent disease can be managed expectantly, most patients require treatment. The therapeutic approach is driven by physician recommendation, patient choice, age, fitness and comorbidities. Young, fit patients often receive combination chemoimmunotherapy, including high dose cytarabine, with autologous stem cell transplant. Recent data has indicated benefit from maintenance rituximab following autologous stem cell transplant. Ongoing trials are investigating combinations of chemotherapy and targeted agents as well as the role of minimal residual disease guided therapy. Older, less fit patients often receive bendamustine and rituximab or anthracycline based regimens. Maintenance rituximab is typically administered in older MCL patients after anthracycline based chemotherapy although its use after bendamustine based therapy is not supported by current data. Current trials focus on refining this regimen with the addition of targeted agents. In the relapsed and refractory setting, novel agents have demonstrated activity although durability of responses remains unsatisfactory.

Prevention and treatment of relapse after stem cell transplantation in lymphoid malignancies

Relapse is now the major cause of treatment failure after allogeneic HSCT (alloHSCT). Many novel strategies to address this critical issue are now being developed and tested. At the 3rd International Workshop on Biology, Prevention, and Treatment of Relapse held in Hamburg, Germany in November 2016, international experts presented and discussed recent developments in the field. Some approaches may be applicable to a wide range of patients after transplant, whereas some may be very disease-specific. We present a report from the session dedicated to issues related to prevention and treatment of relapse of lymphoid malignancies after alloHSCT. This session included detailed reviews as well as forward-looking commentaries that focused on Hodgkin lymphoma, chronic lymphocytic leukemia and mantle cell lymphoma, diffuse large cell and follicular lymphoma, and multiple myeloma.