Frontline bortezomib, rituximab, cyclophosphamide, doxorubicin, and prednisone (VR-CAP) versus rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in transplantation-ineligible patients with newly diagnosed mantle cell lymphoma: final overall survival results of a randomised, open-label, phase 3 study

Clinical outcomes and therapeutic modalities in older Chinese patients with MCL: a multi-center real-world retrospective study

BACKGROUND AND AIMS

Mantle cell lymphoma (MCL), an uncommon lymphoma subtype, is clinically characterized by its heterogenous behavior. Established prediction system including several clinical and biological parameters can help in determining the aggressiveness of MCL in younger patients. However, there are limited parameters on predicting the clinical outcome of older patients. The present study was performed to identify the prognostic factors and optimal treatment modalities in older Chinese MCL patients.

METHODS

Patients (age ≥ 65 yrs) with MCL from 19 comprehensive hospitals in China were included. Clinical characteristics, therapeutic strategies, progression-free survival (PFS) and overall survival (OS) time of these patients were collected.

RESULTS

Totally, 259 eligible patients were enrolled. The median age of patients was 69 years (range, 65-88). The median of PFS and OS were 29 months (95%CI: 26-37) and 76 months (95%CI: 61-96) months, respectively. Multivariate regression analysis determined that ECOG score ≥ 2, high MIPI score and absence of maintenance treatment were independently associated with poorer PFS of MCL patients; while ECOG score ≥ 2 and absence of maintenance treatment were independently correlated with a poorer OS. Patients with MCL who received BTKi-containing regimens or maintenance therapy showed significantly longer PFS and OS than those who did not receive these therapies. Maintenance treatment can improve the survival rate of older patients with MCL regardless of TP53 status.

CONCLUSIONS

ECOG ≥ 2, high MIPI score, and absence of maintenance therapy were associated with poorer survival outcomes for older Chinese MCL patients. Maintenance therapy and BTKi-containing regimens have been shown to increase the survival rate of older Chinese MCL patients.

Esophageal involvement of mantle cell lymphoma presenting with multiple lymphomatous polyposis: A single-center study

BACKGROUND

In addition to nodal lesions, over 30% of mantle cell lymphomas (MCLs) also have gastrointestinal involvement, characteristically presenting as multiple lymphomatous polyposis (MLP), which rarely involve the esophagus. Most related papers have been case reports, and no comprehensive studies have been conducted; thus, the actual clinical situation has remained unknown for a long time.

AIM

To elucidate the actual clinical situation of esophageal involvement of MCL presenting with MLP, including its prognosis.

METHODS

From January 2001 to December 2021, among MCL patients whose gastrointestinal lesions were histopathologically confirmed by endoscopic biopsy at our center, 6 patients with MLP in the esophagus were selected. We retrospectively examined the clinical features of these patients, including their prognosis.

RESULTS

In all patients, multiple lesions were present in the gastrointestinal tract other than the esophagus and in the lymph nodes throughout the body, and most patients also had lesions involving the bone marrow or spleen. Most of the treatments include chemotherapy, with a 50% survival period of less than 2 years and a 5-year survival rate of approximately 30%, indicating a poor prognosis.

CONCLUSION

Patients with esophageal involvement of the MCL who presented with MLP had a large tumor burden and poor survival.

SOHO State of the Art Updates and Next Questions | The Current State of CAR T-Cell Therapy and Bispecific Antibodies in Mantle Cell Lymphoma

MCL remains incurable, and patients who relapse post BTK inhibitors have poor outcomes. BsAbs and CAR T cell therapy are novel strategies to treat patients with R/R MCL. These therapies exhibit favorable outcomes and side effect profiles in a previously dismal space. This review looks to detail the current data available for BsAbs and CAR T cell therapy in R/R MCL, and how are current treatment paradigm is shifting to incorporate these novel agents.

Challenges of treating mantle cell lymphoma in older adults

Mantle cell lymphoma (MCL) is a rare, incurable B-cell non-Hodgkin lymphoma and over half of patients affected are older adults (≥65 years of age). New targeted treatments for MCL have emerged over the past two decades. Nonetheless, MCL-specific death rates for older adults remain elevated compared with younger adults, demonstrating the challenge of treating this population. The older adult population is at risk for overtreatment or undertreatment. Clinicians must be mindful of how to optimize the holistic care of older adults receiving treatment for MCL. Evaluating fitness through a geriatric assessment (GA) is an important step when choosing therapy. The treatment armamentarium includes both chemotherapy and non-chemotherapy options and toxicities must be considered in the context of the patient's GA and proactively managed. Herein, the treatment of MCL in older adults is reviewed and strategies for choosing treatment are offered to assist in treatment decision-making for this challenging population.

Bortezomib for rituximab-refractory immune-mediated thrombotic thrombocytopenic purpura in the caplacizumab era: an Italian multicenter study

BACKGROUND

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) patients are not responsive to standard rituximab in approximately 10% to 15% of cases, and oral immunosuppressants showed controversial results with significant toxicity. Targeting plasma cells with bortezomib appears promising, but the available evidence is scarce and stems only from isolated reports in the precaplacizumab era.

OBJECTIVES

To evaluate the safety and efficacy of bortezomib in rituximab-refractory iTTP patients.

METHODS

We conducted a retrospective observational multicenter study among 13 Italian iTTP treating centers, collecting data from May 2017 to May 2023 (caplacizumab was licensed in Italy in January 2020).

RESULTS

Bortezomib was effective in 10/17 patients (59%). Eleven were treated in the acute phase (9/11 responders, 82%, allowing discontinuation of caplacizumab in 5/6 treated patients), and 7 during clinical remission (2/7 responders, 28%). Responses occurred at a median time of 30 days, but 3 patients responded after 4 months. The median duration of response was 22 months (IQR, 10-38), still ongoing in 6 patients at the time of data cutoff. Responders had fewer previous acute iTTP episodes than nonresponders (median [IQR], 1 [1,2] vs 5.5 [2-7]; P = .03). Eight subjects (47%) reported toxicities, mostly in those treated with ≥2 cycles.

CONCLUSION

Durable responses to bortezomib were registered in about 60% of multirefractory iTTP patients with mild to moderate toxicities. The occurrence of late responses (ie, after 30 days) suggests a "watchful waiting" approach after bortezomib treatment.

Diagnosis and management of mantle cell lymphoma: a consensus practice statement from the Australasian Lymphoma Alliance

Mantle cell lymphoma (MCL) is a clinically heterogeneous B-cell neoplasm with unique clinicopathological features, accounting for 5% of all non-Hodgkin lymphoma. Although for many chemoimmunotherapy can lead to durable remissions, those with poor baseline prognostic factors, namely blastoid morphology, TP53 aberrancy and Ki67 >30%, will have less durable responses to conventional therapies. With this in mind, clinical trials have focused on novel targeted therapies to improve outcomes. This review details the recent advances in the understanding of MCL biology and outlines the recommended diagnostic strategies and evidence-based approaches to treatment.

SOHO State of the Art Updates and Next Questions: Treatment Evolution of Mantle Cell Lymphoma: Navigating the Different Entities and Biological Heterogeneity of Mantle Cell Lymphoma in 2024

Progress in mantle cell lymphoma (MCL) has led to significant improvement in outcomes of patients even in the real world (RW) setting albeit to a lesser degree. In parallel to the demonstration of benefit using combination therapy with rituximab plus high-dose cytarabine (R-AraC) as well as dose intensive therapy-autologous stem cell transplantation (DIT-ASCT) consolidation and maintenance, it became clear over the last 2 decades that MCL is a highly heterogenous disease at the molecular level, explaining differences observed in clinical behavior and response to therapy. While clinical prognostic factors and models have helped stratify patients with distinct outcomes, they failed to help guide therapy. The identification of molecular high-risk (HR) features, in particular, but not only, p53 aberrations (including mutations and deletions [del]), as well as complex karyotype (CK), has allowed to identify subsets of patients with poorer outcomes (median overall survival [OS] <2 years) regardless of conventional therapies used. The constant pattern of relapse seen in MCL has fueled sustained and productive efforts, with 7 novel agents approved in the United States (US), showing high and durable efficacy even in HR and chemo-refractory patients and likely curing a subset of patients in the relapsed or refractory (R/R) setting. Progress in diagnostics, in particular next-generation sequencing (NGS), which is accessible in routine practice nowadays, can help recognize patients with HR features, well beyond MIPI or Ki-67 prognostication, although the impact on decision making is still unclear. The era of integrating novel agents into our prior standard of care (SOC) has begun with a confirmed benefit, for example, ibrutinib (Ib) in the TRIANGLE study, defining the first new potential SOC in younger patients in over 30 years. Expanding on novel agents, either in combination, sequentially or to replace chemotherapy altogether, using biological doublets or triplets has led to a median progression-free survival (PFS) in excess of 72 months, certainly competitive with prior SOC and will continue to reshape the management of MCL patients. Achieving minimal residual disease negative (MRD-ve) status is becoming a new endpoint in MCL, and customizing maintenance and/or de-escalation/consolidation strategies is within reach, although it will require prospective, built-in MRD-based approaches, with the goal of eliminating subclinical disease and not simply delaying time to relapse. Taking into account the biological diversity of MCL is now feasible in routine clinical practice and has already helped recognize what not to do for HR patients (i.e., avoid intensive induction chemotherapy and/or ASCT for p53 mutated patients) as well as identify promising novel options. Ongoing and future work will help expand on these dedicated approaches, to further improve the management and outcomes of all MCL patients.

[A multicenter retrospective study discussion on maintenance treatment strategies for mantle cell lymphoma]

Objective: This study aims to explore the survival advantages of different maintenance strategies for MCL. Methods: Clinical data of 693 newly diagnosed MCL patients in multi-centers admitted from April 1999 to December 2019 were collected. 309 cases received maintenance treatment. The characteristics of patients in different maintenance treatment groups were summarized and Kaplan-Meier survival and prognosis analysis were conducted. Results: The overall 3-year and 5-year progression-free survival (PFS) rates were (73.5±2.9) % and (53.6±4.3) %, respectively. The 3-year and 5-year overall survival (OS) rates were (94.2±1.5) % and (82.7±3.2) %, respectively. The clinical features of different maintenance treatment groups were generally consistent. The 3-year PFS rates of rituximab maintenance, lenalidomide maintenance, BTK inhibitor maintenance and dual-drug maintenance were (70.4±4.1) %, (69.1±7.6) %, (86.9±5.0) %, and (80.4±5.1) %, respectively. Corresponding 3-year OS rates were (92.9±2.4) %, (97.3±2.7) %, (97.9±2.1) %, and (95.3±2.7) %, respectively. There were no significant difference in different groups (P=0.632, 0.313). Survival analysis identified the MCL International Prognostic Index (MIPI) high-risk group and achieving complete remission before maintenance treatment as independent risk factors for PFS. The MIPI high-risk group, high-dose cytarabine application, treatment lines, and early disease progression (POD24) emerged as independent risk factors for OS. Conclusion: Comparing the different maintenance strategies of MCL, the result showed that BTK inhibitors (BTKi) maintenance demonstrated preliminary advantages in survival. Meanwhile, high-risk group according to MIPI and incomplete remission before maintenance treatment were significant factors related to disease progression.

The addition of bortezomib to rituximab, high-dose cytarabine and dexamethasone in relapsed or refractory mantle cell lymphoma-a randomized, open-label phase III trial of the European mantle cell lymphoma network

The therapy of relapsed or refractory (r/r) mantle cell lymphoma (MCL) patients remains a major clinical challenge to date. We conducted a randomized, open-label, parallel-group phase-III trial hypothesizing superior efficacy of rituximab, high-dose cytarabine and dexamethasone with bortezomib (R-HAD + B) versus without (R-HAD) in r/r MCL ineligible for or relapsed after autologous stem cell transplant (ASCT). Primary endpoint was time to treatment failure (TTF), secondary endpoints included response rates, progression free survival, overall survival, and safety. In total, 128 of 175 planned patients were randomized to R-HAD + B (n = 64) or R-HAD (n = 64). Median TTF was 12 vs. 2.6 months (p = 0.045, MIPI-adjusted HR 0.69; 95%CI 0.47-1.02). Overall and complete response rates were 63 vs. 45% (p = 0.049) and 42 vs. 19% (p = 0.0062). A significant treatment effect was seen in the subgroup of patients >65 years (aHR 0.48, 0.29-0.79) and without previous ASCT (aHR 0.52, 0.28-0.96). Toxicity was mostly hematological and attributable to the chemotherapeutic backbone. Grade ≥3 leukocytopenia and lymphocytopenia were more common in R-HAD + B without differences in severe infections between both arms. Bortezomib in combination with chemotherapy can be effective in r/r MCL and should be evaluated further as a therapeutic option, especially if therapy with BTK inhibitors is not an option. Trial registration: NCT01449344.

Ageing microenvironment mediates lymphocyte carcinogenesis and lymphoma drug resistance: From mechanisms to clinical therapy (Review)

Cellular senescence has a complex role in lymphocyte carcinogenesis and drug resistance of lymphomas. Senescent lymphoma cells combine with immunocytes to create an ageing environment that can be reprogrammed with a senescence‑associated secretory phenotype, which gradually promotes therapeutic resistance. Certain signalling pathways, such as the NF‑κB, Wnt and PI3K/AKT/mTOR pathways, regulate the tumour ageing microenvironment and induce the proliferation and progression of lymphoma cells. Therefore, targeting senescence‑related enzymes or their signal transduction pathways may overcome radiotherapy or chemotherapy resistance and enhance the efficacy of relapsed/refractory lymphoma treatments. Mechanisms underlying drug resistance in lymphomas are complex. The ageing microenvironment is a novel factor that contributes to drug resistance in lymphomas. In terms of clinical translation, some senolytics have been used in clinical trials on patients with relapsed or refractory lymphoma. Combining immunotherapy with epigenetic drugs may achieve better therapeutic effects; however, senescent cells exhibit considerable heterogeneity and lymphoma has several subtypes. Extensive research is necessary to achieve the practical application of senolytics in relapsed or refractory lymphomas. This review summarises the mechanisms of senescence‑associated drug resistance in lymphoma, as well as emerging strategies using senolytics, to overcome therapeutic resistance in lymphoma.

B-cell non-Hodgkin lymphomas

B-cell lymphomas occur with an incidence of 20 new cases per 100 000 people per year in high-income countries. They can affect any organ and are characterised by heterogeneous clinical presentations and courses, varying from asymptomatic, to indolent, to very aggressive cases. Since the topic of B-cell non-Hodgkin lymphomas was last reviewed in The Lancet in 2017, a deeper understanding of the biological background of this heterogeneous group of malignancies, the availability of new diagnostic methods, and the development and implementation of new targeted and immunotherapeutic approaches have improved our ability to treat patients. This Seminar provides an overview of the pathobiology, classification, and prognostication of B-cell non-Hodgkin lymphomas and summarises the current knowledge and standard of care regarding biology and clinical management of the most common subtypes of mature B-cell non-Hodgkin lymphomas. It also highlights new findings in deciphering the molecular background of disease development and the implementation of new therapeutic approaches, particularly those targeting the immune system.

[Targeted therapies in the management of malignant lymphoma - is the end of conventional chemotherapy near?]

Advances in the understanding of the biology of malignant lymphoma has facilitated the development of numerous molecularly targeted therapies. The incorporation of these precision therapeutics has produced more effective and often less-toxic treatment regimens leading to a significant improvement of treatment outcomes for individuals with lymphoid malignancies.In relapsed diseases, molecularly targeted therapeutic approaches have demonstrated superior outcomes compared to conventional chemotherapy, leading to a growing number of patients being treated entirely chemotherapy-free. This review outlines the current landscape of targeted therapies for both B-cell (B-NHL) and T-cell non-Hodgkin lymphomas (T-NHL) and provides an overview of targeted agents currently approved for the treatment of malignant lymphoma.

Phase I study of bendamustine, rituximab, ibrutinib, and venetoclax in relapsed, refractory mantle cell lymphoma

This dose-finding study evaluated safety of venetoclax plus Bendamustine-Rituximab-Ibrutinib in relapsed/refractory MCL. Six 28-day cycles were administered in a 3 + 3 dose-escalation design. Dose level 1 (DL1) included Bendamustine 90 mg/m2 on day 1-2, Rituximab 375 mg/m2 on day 1, and Ibrutinib 560 mg daily. Venetoclax was dosed with ramp-up and at 400 mg starting in Cycle 2 for 5 days. The most common adverse events were thrombocytopenia (80%), constipation (60%), and fatigue (60%). Rare hematologic grade 3-4 AEs, 1 dose-limiting toxicity at DL1 (prolonged grade 3 thrombocytopenia), and delayed hematologic toxicity were observed. DL-1 with Bendamustine dose-reduced to 70 mg/m2 (n = 3) revealed no significant toxicity. The overall and complete response rates were both 80% (8/10). This study underscored that venetoclax combined with chemoimmunotherapy is complicated by hematologic toxicity, limiting future development. Although a maximum tolerated dose was not formally established given early study closure, this study demonstrated preliminary tolerability and efficacy of Bendamustine-Rituximab-Ibrutinib-Venetoclax at DL-1.

Survival Outcomes of Patients with Mantle Cell Lymphoma: A Retrospective, 15-Year, Real-Life Study

Mantle cell lymphoma (MCL) prognosis has significantly improved in recent years; however, the possible survival benefit of new treatment options should be evaluated outside of clinical trials. We investigated 73 consecutive MCL patients managed from 2006 to 2020. For younger patients <65 years old, the median PFS was 72 months and we reported a 2-year, 5-year, and 10-year PFS of 73%, 62%, and 41%; median OS was not reached and we reported a 2-year, 5-year, and 10-year OS of 88%, 82%, and 66%. For patients aged 75 years or older, the median PFS was 36 months and we reported a 2-year, 5-year, and 10-year PFS of 52%, 37%, and 37%; median OS was not reached and we reported a 2-year, 5-year, and 10-year OS of 72%, 55%, and 55%. The median PFS was significantly reduced for patients treated between 2006 and 2010 compared to patients treated between 2011 and 2015 (p = 0.04). Interestingly, there was a trend towards improved OS for patients treated between 2016 and 2020 compared to between 2006 and 2010 and between 2011 and 2015 (5-year OS was 91%, 44%, and 33%). These findings could be due to the introduction of BR as a first-line regimen for elderly patients and to the introduction of ibrutinib as a second-line regimen.

Novel treatment for mantle cell lymphoma - impact of BTK inhibitors and beyond

Mantle cell lymphoma (MCL) primarily affects older adults, accounting for 3-10% of all non-Hodgkin lymphoma (NHL) in western countries. The disease course of MCL is heterogenous; driven by clinical, cytogenetics, and molecular features that shape differences in outcomes, including proliferation index, MIPI scores, and mutational profile such as TP53 aberration. The advent of novel agents has fundamentally evolved the treatment landscape for MCL with treatment strategies that can now be more effectively tailored based on both patient- and disease-specific factors. In this review, we discuss the major classes of novel agents used for the treatment of MCL, focusing on efficacy and notable toxicities of BTK inhibitors. We further examine effective novel combination regimens and, lastly, discuss future directions for the evolution of targeted approaches for the treatment of MCL.

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.

Nine-year follow-up of lenalidomide plus rituximab as initial treatment for mantle cell lymphoma

Although chemoimmunotherapy is the current standard of care for initial treatment of mantle cell lymphoma (MCL), newer data suggest that there may be a role for a chemotherapy-free approach. We report the 9-year follow-up results of a multicenter, phase 2 study of lenalidomide plus rituximab (LR) as the initial treatment of MCL. The LR doublet is used as induction and maintenance until progression, with optional discontinuation after 3 years. We previously reported an overall response rate of 92% in evaluable patients, with 64% achieving a complete response. At a median follow-up of 103 months, 17 of 36 evaluable patients (47%) remain in remission. The 9-year progression-free survival and overall survival were 51% and 66%, respectively. During maintenance, hematologic adverse events included asymptomatic grade 3 or 4 cytopenia (42% neutropenia, 5% thrombocytopenia, and 3% anemia) and mostly grade 1 to 2 infections managed in the outpatient setting (50% upper respiratory infections, 21% urinary tract infections, 16% sinusitis, 16% cellulitis, and 13% pneumonia, with 5% requiring hospitalization). More patients developed grade 1 and 2 neuropathy during maintenance therapy (29%) than during induction therapy (8%). Twenty-one percent of patients developed secondary malignancies, including 5% with invasive malignancies, whereas the remainder were noninvasive skin cancers treated with local skin-directed therapy. Two patients permanently discontinued therapy because of concerns of immunosuppression during the COVID-19 pandemic. With long-term follow-up, LR continues to demonstrate prolonged, durable responses with manageable safety as initial induction therapy. This trial was registered at www.clinicaltrials.gov as #NCT01472562.

Combined therapy with ibrutinib and bortezomib followed by ibrutinib maintenance in relapsed or refractory mantle cell lymphoma and high-risk features: a phase 1/2 trial of the European MCL network (SAKK 36/13)

Background

The Bruton's tyrosine kinase inhibitor ibrutinib and the proteasome inhibitor bortezomib have single-agent activity, non-overlapping toxicities, and regulatory approval in mantle cell lymphoma (MCL). In vitro, their combination provides synergistic cytotoxicity. In this investigator-initiated phase 1/2 trial, we established the recommended phase 2 dose of ibrutinib in combination with bortezomib, and assessed its efficacy in patients with relapsed or refractory MCL.

Methods

In this phase 1/2 study open in 15 sites in Switzerland, Germany and Italy, patients with relapsed or refractory MCL after ≤2 lines of chemotherapy and both ibrutinib-naïve and bortezomib-naïve received six cycles of ibrutinibb and bortezomib, followed by ibrutinib maintenance. For the phase 1 study, a standard 3 + 3 dose escalation design was used to determine the recommended phase 2 dose of ibrutinib in combination with bortezomib. The primary endpoint in phase 1 was the dose limiting toxicities in cycle 1. The phase 2 study was an open-label, single-arm trial with a Simon's two-stage min-max design, with a primary endpoint of overall response rate (ORR) assessed by CT/MRI. This study was registered with ClinicalTrials.gov, NCT02356458.

Findings

Between August 2015 and September 2016, nine patients were treated in the phase 1 study, and 49 patients were treated between November 2016 and March 2020 in the phase 2 of the trial. The ORR was 81.8% (90% CI 71.1, 89.8%, CR(u) 21.8%) which increased with continued ibrutinib (median 10.6 months) to 87.3%, (CR(u) 41.8%). 75.6% of patients had at least one high-risk feature (Ki-67 > 30%, blastoid or pleomorphic variant, p53 overexpression, TP53 mutations and/or deletions). In these patients, ibrutinib and bortezomib were also effective with an ORR of 74%, increasing to 82% during maintenance. With a median follow-up of 25.4 months, the median duration of response was 22.7, and the median PFS was 18.6 months. PFS reached 30.8 and 32.9 months for patients with a CR or Cru, respectively.

Interpretation

The combination of ibrutinib and bortezomib shows durable efficacy in patients with relapsed or refractory MCL, also in the presence of high-risk features.

Funding

SAKK (Hubacher Fund), Swiss State Secretariat for Education, Research and Innovation, Swiss Cancer Research Foundation, and Janssen.

Long-term follow-up of rituximab plus bendamustine and cytarabine in older patients with newly diagnosed MCL

The combination of rituximab, bendamustine, and low-dose cytarabine (R-BAC) has been studied in a phase 2 prospective multicenter study from Fondazione Italiana Linfomi (RBAC500). In 57 previously untreated elderly patients with mantle cell lymphoma (MCL), R-BAC was associated with a complete remission rate of 91% and 2-year progression-free survival (PFS) of 81% (95% confidence interval [CI], 68-89). Here, we report the long-term survival outcomes, late toxicities, and results of minimal residual disease (MRD) evaluation. After a median follow-up of 86 months (range, 57-107 months), the median overall survival (OS) and PFS were not reached. The 7-year PFS and OS rates were 55% (95% CI, 41-67), and 63% (95% CI, 49-74), respectively. Patients who responded (n = 53) had a 7-year PFS of 59% (95% CI, 44-71), with no relapse or progression registered after the sixth year. In the multivariate analysis, blastoid/pleomorphic morphology was the strongest adverse predictive factor for PFS (P = .04). Patients with an end of treatment negative MRD had better, but not significant, outcomes for both PFS and OS than patients with MRD-positive (P = 0.148 and P = 0.162, respectively). There was no signal of late toxicity or an increase in secondary malignancies during the prolonged follow-up. In conclusion, R-BAC, which was not followed by maintenance therapy, showed sustained efficacy over time in older patients with MCL. Survival outcomes compare favorably with those of other immunochemotherapy regimens (with or without maintenance), including combinations of BTK inhibitors upfront. This study was registered with EudraCT as 2011-005739-23 and at www.clinicaltrials.gov as #NCT01662050.

Nationwide Assessment of Patient Trajectories in Mantle Cell Lymphoma: The Swedish MCLcomplete Project

Mantle cell lymphoma (MCL) is a B-cell malignancy currently considered incurable. Although some patients obtain prolonged remission after first-line chemoimmunotherapy, many will need several treatment lines. Here, we present a nationwide assessment of treatment strategies, time to progression and survival in MCL. All patients diagnosed with MCL 2006-2018 were identified in the Swedish Lymphoma Register. Information on all lines of therapy was extracted from the medical records. Overall and progression-free survival (OS and PFS) were assessed through August 2021. In total, 1367 patients were included (median age, 71 years) and median follow-up was 6.8 years. Two hundred and one (15%) were managed initially with watch-and-wait, but 1235 (90%) eventually received treatment. The most frequently used first-line regimens were rituximab-bendamustine (BR) (n = 368; 30%) and Nordic MCL2 (n = 342; 28%). During follow-up, 630 patients (46%) experienced relapse/progression and 546 (40%) received second-line treatment. The most frequently used second-line regimen was BR (n = 185; 34%) but otherwise a wide variety of second-line treatments were used. Further, 382 and 228 patients experienced a second or third relapse/progression, respectively. Median PFS after first (PFS-1), second (PFS-2), third (PFS-3), and fourth (PFS-4) treatment lines was 29.4, 8.9, 4.3, and 2.7 months. Patients with early progression, defined as a PFS-1 <24 months, had an inferior median OS of 13 versus 37 months in patients with later relapse. For patients treated with frontline BR, however, time to relapse had no impact on later outcome. By use of nationwide population-based data, we provide important benchmarks for future studies of all treatment lines in MCL.

Efficacy of front-line immunochemotherapy for transplant-ineligible mantle cell lymphoma: A network meta-analysis of randomized controlled trials

BACKGROUND

There is no standard first-line immunochemotherapy regimen for transplant-ineligible patients with mantle cell lymphoma (MCL) currently, and the efficacy of various treatment remains unclear.

METHODS

We conducted a Bayesian network meta-analysis (NMA) of all eligible randomized controlled trials. Pairwise comparisons and ranking of different first-line treatment options were performed.

RESULTS

Nine studies were included in the NMA, involving a total of 2897 MCL patients. The BR-Ibrutinib+R regimen showed the best progression-free survival (PFS), with a surface under the cumulative ranking curve (SUCRA) of 0.89 and probability of being the best treatment (PbBT) of 69%. The VR-CAP regimen was the most potential intervention to improve overall survival (OS), with a SUCRA of 0.89 and PbBT of 63%. Compared with the R-CHOP regimen, the BR regimen achieved a better PFS (hazard ratio [HR] 0.45 [95% credible interval 0.2-0.96]). The BR-Ibrutinib+R regimen (HR 0.14 [0.02-0.99]), BR+R regimen (HR 0.19 [0.034-0.99]), and BR regimen (HR 0.3 [0.08-1.03]) were superior to CHOP regimen with better PFS. The R-FC regimen (HR 2.27 [1.01-5.21]) or FC regimen (HR 3.17 [1.15-8.71]) was inferior to the VR-CAP regimen with a worse OS.

CONCLUSIONS

Our study presents the most promising first-line treatment strategy for transplant-ineligible MCL patients in terms of PFS and OS, which provides innovative treatment strategy for MCL treatment.

Mantle cell lymphoma-Update on molecular biology, prognostication and treatment approaches

Mantle cell lymphoma (MCL) is clinically characterized by its heterogenous behavior with courses ranging from indolent cases that do not require therapy for years to highly aggressive MCL with very limited prognosis. The development and implementation of new targeted and immunotherapeutic approaches have already improved therapeutic options especially for refractory or relapsed disease. Nevertheless, to further optimize MCL treatment, early identification of individual risk profile and risk-adapted, patient-tailored choice of therapeutic strategy needs to be prospectively incorporated in clinical patient management. This review summarizes the current knowledge and standard of care regarding biology and clinical management of MCL, highlighting the implementation of new therapeutic approaches especially targeting the immune system.

Evaluation of Bortezomib-BeEAM (2BeEAM) as Chemotherapy Regimen Prior to ASCT in Patients with Mantle Cell Lymphoma

(1) Background: First-line therapy in fit MCL patients may comprise high-dose chemotherapy (HDCT) with autologous transplantation to consolidate remission before maintenance treatment. However, optimization of HDCT is an unmet clinical need given the substantial relapse rate of first-line treatment, while the use of bortezomib is a promising candidate to be added to standard HDCT. (2) Methods: We analyzed 11 consecutive patients with MCL who received bortezomib added to standard BeEAM (2BeEAM) HDCT at a single academic institution. We assessed safety, feasibility, toxicities, and survival rates. (3) Results: All patients had stage III or IV disease. We found that six patients (55%) developed new or worsening of preexisting peripheral neuropathy following administration of 2BeEAM HDCT. One patient relapsed within the first six months after HDCT, whereas three patients never reached complete remission. After a median follow-up of 22 months, the PFS was 64% and the OS 64% at the last follow-up assessment. At this time, 55% of patients were in CR. (4) Conclusions: The use of bortezomib added to standard BeEAM HDCT is associated with relevant toxicities, particularly with regards to additional neuropathy. Moreover, the anti-lymphoma efficacy of 2BeEAM HDCT appears to be modest; therefore, other therapeutic options should be evaluated for consolidation in this patient group.

How I manage mantle cell lymphoma: indolent versus aggressive disease

Mantle cell lymphoma (MCL) is a mature B-cell lymphoma with a variable clinical course and historically poor prognosis. Management is challenging in part due to the heterogeneity of the disease course, with indolent and aggressive subtypes now well recognised. Indolent MCL is often characterised by a leukaemic presentation, SOX11 negativity and low proliferation index (Ki-67). Aggressive MCL is characterised by rapid onset widespread lymphadenopathy, extra-nodal involvement, blastoid or pleomorphic histology and high Ki-67. Tumour protein p53 (TP53) aberrations in aggressive MCL are recognised with clear negative impact on survival. Until recently, trials have not addressed these specific subtypes separately. With the increasing availability of targeted novel agents and cellular therapies, the treatment landscape is constantly evolving. In this review, we describe the clinical presentation, biological factors, and specific management considerations of both indolent and aggressive MCL and discuss current and potential future evidence which may help move to a more personalised approach.

Molecular Aspects and Therapeutic Implications of Herbal Compounds Targeting Different Types of Cancer

Due to genetic changes in DNA (deoxyribonucleic acid) sequences, cancer continues to be the second most prevalent cause of death. The traditional target-directed approach, which is confronted with the importance of target function in healthy cells, is one of the most significant challenges in anticancer research. Another problem with cancer cells is that they experience various mutations, changes in gene duplication, and chromosomal abnormalities, all of which have a direct influence on the potency of anticancer drugs at different developmental stages. All of these factors combine to make cancer medication development difficult, with low clinical licensure success rates when compared to other therapy categories. The current review focuses on the pathophysiology and molecular aspects of common cancer types. Currently, the available chemotherapeutic drugs, also known as combination chemotherapy, are associated with numerous adverse effects, resulting in the search for herbal-based alternatives that attenuate resistance due to cancer therapy and exert chemo-protective actions. To provide new insights, this review updated the list of key compounds that may enhance the efficacy of cancer treatment.

Efficacy and safety of ibrutinib in mantle cell lymphoma: A systematic review and meta-analysis

OBJECTIVES

Since the US Food and Drug Administration (FDA) approved ibrutinib to treat patients with refractory/relapsed mantle cell lymphoma (R/R MCL), it is used in clinical trials, whether as a single agent or in combination with other chemotherapy agents. The efficacy and safety of ibrutinib administration alone or in combinations have not been studied systematically. This study systematically reviewed the efficacy and safety of ibrutinib-containing regimens for the treatment of patients with MCL.

EVIDENCE ACQUISITION

We performed a systematic search in PubMed, Cochrane CENTRAL, Embase, Web of Science, and Scopus. Then, a team of independent reviewers selected relevant studies and extracted the data.

RESULTS

From a total of 1,436 studies, 12 trials were eligible. The overall response rates (ORRs) of patients with R/R MCL receiving single-agent ibrutinib ranged between 62.7% to 93.8%, and the ORRs of ibrutinib combinations ranged from 74 to 88%. In patients with newly diagnosed MCL receiving ibrutinib and rituximab, ORR ranged from 84 to 100%. The highest progression-free survival (PFS) was reported in patients receiving ibrutinib and rituximab (43 months). The meta-analysis performed on adverse events (AEs) demonstrated that single-agent ibrutinib had a high risk of bleeding, nausea, and diarrhea.

CONCLUSION

Single-agent ibrutinib showed acceptable efficacy and safety in the treatment of patients with MCL. Moreover, combining ibrutinib with other agents such as rituximab, venetoclax, and ublituximab can increase its efficacy and reduce chemotherapy-induced resistance in most cases; however, in the case of combination therapy, patients need to be monitored more strictly in terms of AEs. In our review, the ibrutinib and rituximab combination showed promising results in patients with R/R MCL. Also, this combination showed favorable efficacy and safety in patients with newly diagnosed untreated MCL, making it a great candidate to be studied more in large and well-designed trials.

Diagnostic and therapeutic potential of protease inhibition

Proteases are enzymes that hydrolyze peptide bonds in proteins and peptides; thus, they control virtually all biological processes. Our understanding of protease function has advanced considerably from nonselective digestive enzymes to highly specialized molecular scissors that orchestrate complex signaling networks through a limited proteolysis. The catalytic activity of proteases is tightly regulated at several levels, ranging from gene expression through trafficking and maturation to posttranslational modifications. However, when this delicate balance is disturbed, many diseases develop, including cancer, inflammatory disorders, diabetes, and neurodegenerative diseases. This new understanding of the role of proteases in pathologic physiology indicates that these enzymes represent excellent molecular targets for the development of therapeutic inhibitors, as well as for the design of chemical probes to visualize their redundant activity. Recently, numerous platform technologies have been developed to identify and optimize protease substrates and inhibitors, which were further used as lead structures for the development of chemical probes and therapeutic drugs. Due to this considerable success, the clinical potential of proteases in therapeutics and diagnostics is rapidly growing and is still not completely explored. Therefore, small molecules that can selectively target aberrant protease activity are emerging in diseases cells. In this review, we describe modern trends in the design of protease drugs as well as small molecule activity-based probes to visualize selected proteases in clinical settings.

Treatment Landscape of Relapsed/Refractory Mantle Cell Lymphoma: An Updated Review

Mantle cell lymphoma (MCL) accounts for nearly 2-6% of all non-Hodgkin lymphoma (NHL) cases, with a steady incidence increase over the past few decades. Although many patients achieve an adequate response to the upfront treatment, the short duration of remission with rapid relapse is challenging during MCL management. In this regard, there is no consensus on the best treatment options for relapsed/refractory (R/R) disease, and the international guidelines demonstrate wide variations in the recommended approaches. The last decade has witnessed the introduction of new agents in the treatment landscape of R/R MCL. Since the introduction of Bruton's tyrosine kinase (BTK) inhibitors, the treatment algorithm and response of R/R MCL patients have dramatically changed. Nevertheless, BTK resistance is common, necessitating further investigations to develop novel agents with a more durable response. Novel agents targeting the B-cell receptor (BCR) signaling have exhibited clinical activity and a well-tolerable safety profile. However, as the responses to these novel agents are still modest in most clinical trials, combination strategies were investigated in pre-clinical and early clinical settings to determine whether the combination of novel agents would exhibit a better durable response than single agents. In this report, we provide an updated literature review that covers recent clinical data about the safety and efficacy of novel therapies for the management of R/R MCL.

Aggressive Lymphome (DLBCL, MCL) – was ist neu?

DLBCL. Biologie Der kürzlich publizierte „LymphGen-Algorithmus“ differenziert 7 genetische Subtypen, die sich in der Aktivierung onkogener Signalwege, im Genexpressionsmuster, im Tumormikromilieu, der Überlebenswahrscheinlichkeit und potenzieller zielgerichteter Therapien unterscheiden.

Erstlinientherapie Der Einsatz des neuen Antikörper-Wirkstoff-Konjugats Polatuzumab-Vedotin (6 Zyklen der Kombination aus Polatuzumab + R-CHP) waren der bisherigen Erstlinien-Standardtherapie mit R-CHOP hinsichtlich 2-Jahres-PFS überlegen. Subgruppenanalysen wiesen vor allem auf eine Wirksamkeit bei Patienten mit Hochrisikofaktoren hin.

Rezidivtherapie Seit Kurzem steht mit dem gegen den CD19 gerichteten Antikörper Tafasitamab in Kombination mit dem Immunmodulator Lenalidomid eine wirksame Rezidivtherapie für jene Patientengruppe zur Verfügung, die für eine Hochdosistherapie nicht geeignet ist. In 2 Phase-III-Studien wurde kürzlich bereits im 1. Rezidiv eine Überlegenheit von CAR-T-Zellen gegenüber dem bisherigen Standard der Hochdosistherapie, gefolgt von aPBSCT, gezeigt. Mit den bispezifischen, T-Zell-rekrutierenden CD3 / CD20-Antikörpern Mosunetuzumab, Epcoritamab und Glofitamab sind derzeit weitere vielversprechende immuntherapeutische Ansätze Gegenstand aktueller Phase I/II-Studien.

MCL. Biologie Trotz der weiteren Entschlüsselung des genetischen Hintergrunds des MCL ist weiterhin nur für TP53 eine klinische Relevanz nachgewiesen.

Erstlinientherapie In der Ära der zielgerichteten Therapiestrategien wird derzeit die Bedeutung des BTK-Inhibitors Ibrutinib für die Erstlinien- und Erhaltungstherapie des MCL evaluiert. Für ältere Patienten erwies sich kürzlich die Kombination des Proteasom-Inhibitors Bortezomib, Rituximab, Cyclophosphamid, Doxorubicin und Prednisolon (VR-CAP) der bisherigen Standardtherapie mit R-CHOP überlegen. Für ältere Patienten, die für intensivere Therapieregime nicht geeignet sind, führte die Erweiterung des klassischen Regimes Rituximab + Bendamustin um Ibrutinib zu einer deutlichen Verbesserung des PFS.

Rezidivtherapie Für das rezidivierte/refraktäre MCL wurden neben dem seit Jahren zugelassenen Ibrutinib kürzlich auch die beiden Next-Generation-BTK-Inhibitoren Acalabrutinib and Zanubrutinib zugelassen. Der bcl1-Inhibitor Venetoclax bietet für Hochrisikopatienten, die nach vorangegangener Therapie mit Ibrutinib ein Rezidiv erlitten, eine vielversprechende Behandlungsmöglichkeit. Bezüglich immuntherapeutischer Therapieansätze erfolgte kürzlich die Zulassung des CD19-CAR-T-Zell-Konstrukts Brexucabtagene autoleucel ab dem 2. Rezidiv.

SOHO State of the Art Updates and Next Questions: Managing Relapsed Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is a rare subtype of B-cell non-Hodgkin lymphoma i.e., incurable with current therapies. While some patients experience prolonged remissions following initial therapy, most will have a relapsing-remitting course requiring several lines of treatment over the course of their disease. Several targeted therapies are now available to treat patients with relapsed MCL. The Bruton's tyrosine kinase (BTK) inhibitors, including ibrutinib, acalabrutinib, and zanubrutinib, are highly active in MCL and currently approved for treating patients with relapsed disease. Bortezomib and lenalidomide are available as monotherapy or in combination with other agents. Venetoclax is active and can be considered for use in relapsed MCL, although it is not currently approved by regulatory agencies. Chimeric antigen receptor T-cell (CAR-T) therapy with brexucabtagene autoleucel yields high response rates and is now approved for patients with relapsed MCL. Allogeneic stem cell transplant remains an option for a small subset of medically fit and motivated patients who have progressed through multiple lines of therapy, although its use is limited by substantial toxicity. There is currently no standard approach to sequencing therapies for patients with relapsed MCL, and the ability to utilize disease biologic and clinical characteristics to guide treatment decisions in this setting remains limited. In this review, we summarize the current evidence to guide the management of patients with relapsed MCL, review emerging agents and combination therapies that are under investigation, and outline our current treatment approach for these patients.

Ibrutinib plus Bendamustine and Rituximab in Untreated Mantle-Cell Lymphoma

BACKGROUND

Ibrutinib, a Bruton's tyrosine kinase inhibitor, may have clinical benefit when administered in combination with bendamustine and rituximab and followed by rituximab maintenance therapy in older patients with untreated mantle-cell lymphoma.

METHODS

We randomly assigned patients 65 years of age or older to receive ibrutinib (560 mg, administered orally once daily until disease progression or unacceptable toxic effects) or placebo, plus six cycles of bendamustine (90 mg per square meter of body-surface area) and rituximab (375 mg per square meter). Patients with an objective response (complete or partial response) received rituximab maintenance therapy, administered every 8 weeks for up to 12 additional doses. The primary end point was progression-free survival as assessed by the investigators. Overall survival and safety were also assessed.

RESULTS

Among 523 patients, 261 were randomly assigned to receive ibrutinib and 262 to receive placebo. At a median follow-up of 84.7 months, the median progression-free survival was 80.6 months in the ibrutinib group and 52.9 months in the placebo group (hazard ratio for disease progression or death, 0.75; 95% confidence interval, 0.59 to 0.96; P = 0.01). The percentage of patients with a complete response was 65.5% in the ibrutinib group and 57.6% in the placebo group (P = 0.06). Overall survival was similar in the two groups. The incidence of grade 3 or 4 adverse events during treatment was 81.5% in the ibrutinib group and 77.3% in the placebo group.

CONCLUSIONS

Ibrutinib treatment in combination with standard chemoimmunotherapy significantly prolonged progression-free survival. The safety profile of the combined therapy was consistent with the known profiles of the individual drugs. (Funded by Janssen Research and Development and Pharmacyclics; SHINE ClinicalTrials.gov number, NCT01776840.).

First-Line Autologous Stem Cell Transplantation for Mantle Cell Lymphoma: A Systematic Analysis and Treatment Recommendation

Background

In the era of immunotherapy, autologous stem cell transplantation (ASCT) in first-line therapy in patients with mantle cell lymphoma (MCL) has been a controversial topic. This report aimed to explore the association between ASCT and MCL survival through a systematic review with meta-analysis.

Methods

We performed a systematic search of original articles published from inception to September 2021 using PubMed, MEDLINE, Embase, and Cochrane Library databases.

Results

We included studies that compared ASCT with non-ASCT consolidation in newly diagnosed transplant-eligible MCL. The endpoints were progression-free survival (PFS) and overall survival (OS). There were seven eligible studies (one randomized clinical trial, one prospective cohort study, and five observational studies) published between 2012 and 2021, in which the total number of participants was 3,271. In the non-intensive induction subgroup, patients with ASCT experienced a significant PFS but no OS benefit compared with those without ASCT. In the intensive induction subgroup, the PFS benefit from ASCT still existed but largely attenuated; no OS benefit was observed though only one study was suitable for evaluation. When compared to the rituximab maintenance arm, ASCT had a worse PFS and OS.

Conclusions

In the rituximab plus HiDAC era, the benefit of ASCT as a component of first-line treatment has been weakened. First-line maintenance strategy instead of ASCT seems worth exploring .

New Directions for Mantle Cell Lymphoma in 2022

Mantle cell lymphoma is a rare B-cell non-Hodgkin lymphoma that is clinically and biologically heterogeneous. Risk stratification at the time of diagnosis is critical. One of the most powerful prognostic indices is the Mantle Cell Lymphoma International Prognostic Index-Combined, which integrates an estimate of proliferation (Ki67 index) with the standard Mantle Cell Lymphoma International Prognostic Index clinical factors. In addition, the presence of TP53 mutation is associated with suboptimal response to intensive chemoimmunotherapy and particularly dismal survival outcomes. Given their excellent activity in the relapsed/refractory setting, increasingly, biologically targeted therapeutics-such as covalent Bruton tyrosine kinase inhibitors, lenalidomide, and venetoclax-are being incorporated into "chemotherapy-free" regimens and in combination with established chemoimmunotherapy backbones for treatment-naïve mantle cell lymphoma. In addition, risk-adapted treatment programs are increasingly being studied. These programs tailor treatment according to baseline prognostic factors (e.g., presence of TP53 mutation) and may incorporate biomarkers of response such as minimal residual disease assessment. Although still investigational, these studies present an opportunity to move beyond the biology-agnostic, historical fitness-based treatment selection paradigm and toward a more personalized, tailored treatment approach in mantle cell lymphoma. After Bruton tyrosine kinase inhibitor failure, many promising standard or investigational therapies exist, including CAR T-cell therapy (including brexucabtagene autoleucel and lisocabtagene maraleucel), bispecific antibody therapy targeting CD20-CD3, zilovertamab vedotin (an antibody-drug conjugate that targets ROR1), and the noncovalent Bruton tyrosine kinase inhibitor pirtobrutinib. These new therapies show promising efficacy, even among high-risk patients, and will likely translate to improvements in survival outcomes for patients with progressive mantle cell lymphoma following treatment with a Bruton tyrosine kinase inhibitor.

Mantle cell lymphoma in 2022-A comprehensive update on molecular pathogenesis, risk stratification, clinical approach, and current and novel treatments

The field of mantle cell lymphoma (MCL) has witnessed remarkable progress due to relentless advances in molecular pathogenesis, prognostication, and newer treatments. MCL consists of a spectrum of clinical subtypes. Rarely, atypical cyclin D1-negative MCL and in situ MCL neoplasia are identified. Prognostication of MCL is further refined by identifying somatic mutations (such as TP53, NSD2, KMT2D), methylation status, chromatin organization pattern, SOX-11 expression, minimal residual disease (MRD), and genomic clusters. Lymphoid tissue microenvironment studies demonstrated the role of B-cell receptor signaling, nuclear factor kappa B (NF-kB), colony-stimulating factor (CSF)-1, the CD70-SOX-11 axis. Molecular mechanism of resistance, mutation dynamics, and pathogenic pathways (B-cell receptor (BCR), oxidative phosphorylation, and MYC) were identified in mediating resistance to various treatments (bruton tyrosine kinase (BTK) inhibitors [ibrutinib, acalabrutinib]. Treatment options range from conventional chemoimmunotherapy and stem cell transplantation (SCT) to targeted therapies against BTK (covalent and noncovalent), Bcl2, ROR1, cellular therapy such as anti-CD19 chimeric antigen receptor therapy (CAR-T), and most recently bispecific antibodies against CD19 and CD20. MCL patients frequently relapse. Complex pathogenesis and the management of patients with progression after treatment with BTK/Bcl2 inhibitors and CAR-T (triple-resistant MCL) remain a challenge. Next-generation clinical trials incorporating newer agents and concurrent translational and molecular investigations are ongoing.

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.

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.

Circulating Tumor DNA Predicts Therapeutic Outcome in Mantle Cell Lymphoma

Early changes in ctDNA dynamics are prognostic in untreated MCL.

Bortezomib maintenance after bortezomib-based induction therapy does not improve outcome in untreated MCL.

Mantle cell lymphoma (MCL) is biologically and clinically heterogeneous and would benefit from prognostic biomarkers to guide management. Circulating tumor DNA (ctDNA) is a novel prognostic biomarker in diffuse large B-cell lymphoma that may have applicability in MCL. We analyzed ctDNA dynamics in previously untreated patients with MCL who received induction therapy with bortezomib and DA-EPOCH-R for 6 cycles followed by random assignment to observation or bortezomib maintenance in responding patients in a prospective phase 2 study. Most patients also underwent initial treatment window of bortezomib alone prior to induction. Serum was collected pretreatment, after the window, after cycles 1 and 2, at the end of induction, and at each follow-up visit along with restaging computed tomography scans. Next-generation sequencing was used to identify and quantify ctDNA encoding the immunoglobulin receptor sequences in serum as markers of minimal residual disease. Fifty-three patients were enrolled, with a median follow-up of 12.7 years. Patients without detectable ctDNA after 2 cycles of induction had longer progression-free survival (PFS) and overall survival (OS) compared with those with detectable ctDNA (median PFS, 2.7 vs 1.8 years; overall P = .005; median OS, 13.8 vs 7.4 years; overall P = .03). Notably, in vivo assessment of ctDNA dynamics during the bortezomib window was not prognostic, and there was no difference in PFS or OS with bortezomib maintenance. ctDNA monitoring after induction showed that molecular relapse preceded clinical relapse in some cases. In conclusion, interim ctDNA negativity strongly correlates with improved survival and supports the investigation of response-adapted strategies. This trial was registered at www.clinicaltrials.gov as #NCT00114738.

Therapeutic options for relapsed/refractory mantle cell lymphoma

Mantle cell lymphoma (MCL) is an uncommon subtype of non-Hodgkin lymphoma in which immunochemotherapy, with or without high-dose therapy, and autologous stem cell transplantation remain standard frontline therapies. Despite their clear efficacy, patients inevitably relapse and require subsequent therapy. In this review, we discuss the key therapeutic approaches in the management of relapsed MCL, covering in depth the data supporting the use of covalent Bruton tyrosine kinase (BTK) inhibitors at first or subsequent relapse. We describe the outcomes of patients progressing through BTK inhibitors and discuss the mechanisms of covalent BTKi resistance and treatment options after covalent treatment with BTKi. Options in this setting may depend on treatment availability, patient's and physician's preference, and the patient's age and comorbidity status. We discuss the rapid recent development of anti-CD19 chimeric antigen receptor T-cell therapy, as well as the utility of allogenic stem cell transplantation and novel therapies, such as noncovalent, reversible BTK inhibitors; ROR1 antibody drug conjugates; and bispecific antibodies.

Mantle cell lymphoma treatment options for elderly/unfit patients: A systematic review

Mantle cell lymphoma (MCL) is a rare B-cell non-Hodgkin lymphoma (NHL) that is aggressive and incurable with existing therapies, presenting a significant unmet clinical need. MCL occurs mainly in elderly patients with comorbidities; thus, intense treatment options including allogeneic stem cell transplantation (Allo-SCT) are not feasible. New treatment options are emerging for this elderly/unfit treatment group, we therefore conducted a systematic review to determine whether they offered an advance on the existing recommended treatment, R-CHOP. The search strategies to identify MCL therapies were designed to capture the most relevant studies from 2013 to 2020. Following preferred reporting items for systematic reviews and meta-analyses and population,interventions, observations and study design analysis, R-CHOP, ibrutinib and bendamustine plus rituximab (BR) were taken forward for critical and statistical analysis. All three therapies were effective in increasing the overall survival (OS) and progression-free survival of elderly/unfit patients with MCL. However, none resulted in a significant increase in OS compared to R-CHOP. In addition, R-CHOP had a better toxicity profile when compared to both ibrutinib and BR. We therefore conclude that treatment of elderly/unfit patients with MCL is still a significant unmet clinical need; and suggest that outside of the clinical trial setting, R-CHOP should remain the recommended front-line treatment for this patient group.

Ibrutinib With Rituximab in First-Line Treatment of Older Patients With Mantle Cell Lymphoma

PURPOSE

Most patients with mantle cell lymphoma (MCL) are older. In this study, we investigated the efficacy and safety of a chemotherapy-free combination with ibrutinib and rituximab (IR) in previously untreated older patients with MCL (age ≥ 65 years).

METHODS

We enrolled 50 patients with MCL in this single-institution, single-arm, phase II clinical trial (NCT01880567). Patients with Ki-67% ≥ 50% and blastoid morphology were excluded. Ibrutinib was administered with rituximab up to 2 years with continuation of ibrutinib alone. The primary objective was to assess the overall response rate and safety of IR. In evaluable samples, whole-exome sequencing and bulk RNA sequencing from baseline tissue samples were performed.

RESULTS

The median age was 71 years (interquartile range 69-76 years). Sixteen percent of patients had high-risk simplified MCL international prognostic index. The Ki-67% was low (< 30%) in 38 (76%) and moderately high (≥ 30%-50%) in 12 (24%) patients. The best overall response rate was 96% (71% complete response). After a median follow-up of 45 months (interquartile range 24-56 months), 28 (56%) patients came off study for various reasons (including four progression, 21 toxicities, and three miscellaneous reasons). The median progression-free survival and overall survival were not reached, and 3-year survival was 87% and 94%, respectively. None of the patients died on study therapy. Notably, 11 (22%) patients had grade 3 atrial fibrillation. Grade 3-4 myelosuppression was seen in < 5% of patients. Differential overexpression of CCND1, BIRC3, BANK1, SETBP1, AXIN2, and IL2RA was noted in partial responders compared with patients with complete response.

CONCLUSION

IR combination is effective in older patients with MCL. Baseline evaluation for cardiovascular risks is highly recommended. Randomized trial is needed for definitive conclusions.

Design and synthesis of HDAC inhibitors to enhance the therapeutic effect of diffuse large B-cell lymphoma by improving metabolic stability and pharmacokinetic characteristics

Histone deacetylases (HDAC) are clinically validated and attractive epigenetic drug targets for human cancers. Several HDAC inhibitors have been approved for cancer treatment to date, however, clinical applications have been limited due to the poor pharmacokinetics, bioavailability, selectivity of the HDAC inhibitors and most of them need to be combined with other drugs to achieve better results. Here, we describe our efforts toward the discovery of a novel series of lactam-based derivatives as selective HDAC inhibitors. Intensive structural modifications lead to the identification of compound 24g as the most active Class I HDAC Inhibitor, along with satisfactory metabolic stability in vitro (t_1/2, human = 797 min) and the desirable oral bioavailability (F = 92%). More importantly, compound 24g showed good antitumor efficacy in a TMD-8 xenograft model (TGI = 77%) without obvious toxicity. These results indicated that Class I HDAC Inhibitor could be potentially used to treat certain diffuse large B-cell lymphoma therapeutics.

Sequencing of Novel Therapies for Mantle Cell Lymphoma

OPINION STATEMENT

There is no standard approach to sequencing novel therapies in mantle cell lymphoma (MCL). For initial treatment, intensive induction chemotherapy followed by autologous stem cell transplant and rituximab maintenance remains our preferred approach in young, fit patients. We consider bendamustine plus rituximab or lenalidomide plus rituximab in patients who are ineligible for intensive chemotherapy-based approaches. Bruton's tyrosine kinase inhibitors are our preferred class of agents to use in the second-line setting. When patients inevitably relapse on one of these agents, we proceed with chimeric antigen receptor T-cell (CAR T) therapy in eligible patients, often with the use of bridging therapy with corticosteroids, lenalidomide, or venetoclax. We treat patients who are ineligible for CAR T or clinic trial with venetoclax, lenalidomide, or proteosome inhibitor-based regimens, although efficacy is expected to be limited in this setting with a shortened duration of response to each subsequent line of therapy. Allogeneic stem cell transplant remains an option for carefully selected patients who progress after autologous stem cell transplant and CAR T. Clinical trials involving combinations of novel agents in early lines of therapy are ongoing, and new compounds with unique mechanisms of action are in development. The results of ongoing clinical trials with novel agents will further change the treatment landscape for patients with MCL in the coming years.

How to Diagnose and Treat CD5-Positive Lymphomas Involving the Spleen

Patients with CD5-expressing lymphomas presenting with splenomegaly are frequently diagnosed with chronic lymphocytic leukemia. The most important differential diagnosis is mantle cell lymphoma, both in its classical and leukemic, non-nodal forms, given its prognostic and therapeutic implications. Other small B-cell neoplasms that frequently involve the spleen and occasionally express CD5 include the splenic marginal zone lymphoma, hairy cell leukemia and, rarely, lymphoplasmacytic lymphoma. The frequency of CD5 positivity depends in part on the sensitivity of the detection methods employed. Usually, a combination of morphological, immunophenotypic and molecular findings allows for a precise sub-classification of CD5-positive, low-grade B-cell lymphomas of the spleen. Some of these tumors may display a mixture of small and larger B cells, raising the possibility of more aggressive lymphomas, such as diffuse large B-cell lymphomas (DLBCL). Approximately 5-10% of DLBCL are CD5-positive and some may manifest as primary splenic lesions. When available, the morphology of DLBCL in the splenic tissue is distinctive and a leukemic picture is very rare. In conclusion, the appropriate morphological and clinical context assisted by flow cytometry panels and/or immunohistochemistry allows the differential diagnosis of CD5-positive, non-Hodgkin, B-cell lymphomas involving the spleen.