Nonablative allogeneic stem-cell transplantation for advanced/recurrent mantle-cell lymphoma

SOHO State of the Art Updates and Next Questions | Immunotherapeutic Options for Patients With Mantle Cell Lymphoma Who Progress on BTK Inhibitors

Mantle cell lymphoma is a challenging subtype of B-cell non-Hodgkin lymphoma treat characterized by its aggressive nature and propensity for relapse or refractory (R/R) disease for many patients. The introduction of Bruton's tyrosine kinase inhibitors has significantly improved the outcomes for patients with R/R MCL, but a considerable proportion of patients eventually experience disease progression or develop resistance to these agents. In recent years, immunotherapeutic approaches have emerged as promising treatment options. The treatment landscape is quickly progressing with the FDA approval of CAR-T cell therapy as well as several promising bispecific antibody therapies and antibody-drug conjugates in clinical development. This review article aims to provide a comprehensive overview of the current state of immunotherapeutic options available for patients with R/R MCL.

Is It Possible to Separate the Graft-Versus-Leukemia (GVL) Effect Against B Cell Acute Lymphoblastic Leukemia From Graft-Versus-Host Disease (GVHD) After Hematopoietic Cell Transplant?

Hematopoietic cell transplant is a curative therapy for many pediatric patients with high risk acute lymphoblastic leukemia. Its therapeutic mechanism is primarily based on the generation of an alloreactive graft-versus-leukemia effect that can eliminate residual leukemia cells thus preventing relapse. However its efficacy is diminished by the concurrent emergence of harmful graft-versus-host disease disease which affects healthly tissue leading to significant morbidity and mortality. The purpose of this review is to describe the interventions that have been trialed in order to augment the beneficial graft-versus leukemia effect post-hematopoietic cell transplant while limiting the harmful consequences of graft-versus-host disease. This includes many emerging and promising strategies such as ex vivo and in vivo graft manipulation, targeted cell therapies, T-cell engagers and multiple pharmacologic interventions that stimulate specific donor effector cells.

Is There Still a Role for Transplant for Patients with Mantle Cell Lymphoma (MCL) in the Era of CAR-T Cell Therapy?

OPINION STATEMENT

For years, upfront autologous hematopoietic cell transplant (auto-HCT) has been the standard of care for younger and physically fit mantle cell lymphoma (MCL) patients after chemoimmunotherapy (CIT) induction. Bruton's tyrosine kinase (BTK) inhibitors have proven to be excellent salvage therapies, but their durability remains a question, especially in high-risk (HR) MCL. Allogeneic HCT (allo-HCT) was the only option for long-term remission and possibly cure for MCL relapse after auto-HCT and sometime as upfront consolidation for a young patient with HR MCL (debatable). We have seen a paradigm shift since the FDA approval in July 2020 of the brexucabtagene autoleucel chimeric antigen receptor T (CAR-T) cell therapy for relapsed and refractory (R/R) MCL with an preliminary evidence suggesting CAR-T may overcome known biological risk factors in MCL. Given its safety profile and excellent efficacy, the role of CAR-T among other approved therapies and HCT may need to be better defined. Based on the current evidence, auto-HCT remains a standard frontline consolidation therapy. CAR-T therapy is a preferred option for patients with relapsed/refractory (R/R) MCL, particularly those who failed BTK inhibitors. In certain high-risk MCL patients (such as high ki 67, TP53 alterations, complex karyotype, blastoid morphology, early relapse after initial diagnosis), CAR-T cell therapy may be considered before BTK inhibitors (preferably on a clinical trial). The role of allo-HCT is unclear in the CAR-T era, but remains a viable option for eligible patients who have no access or who have failed CAR-T therapy. Our review discusses current standards and the shifting paradigms in the indications for HCT and the role of CAR-T cell therapy for MCL. Prospective studies tailored based on risk factors are needed to better define the optimal sequences of HCT and cellular therapy and other approved novel therapies.

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.

Allogeneic stem cell transplantation for mantle cell lymphoma-update of the prospective trials of the East German Study Group Hematology/Oncology (OSHO#60 and #74)

Mantle cell lymphoma (MCL) is a non-Hodgkin’s lymphoma with an often aggressive course, incurable by chemotherapy. Consolidation with high-dose therapy and autologous stem cell transplantation (autoSCT) has a low transplant-related mortality but does not lead to a survival plateau. Allogeneic stem cell transplantation (alloSCT) is associated with a higher early mortality, but can cure MCL. To investigate alloSCT for therapy of MCL, we conducted two prospective trials for de novo MCL (OSHO#74) and for relapsed or refractory MCL (OSHO#60). Fifteen and 24 patients were recruited, respectively. Induction was mainly R-DHAP alternating with R-CHOP. Conditioning was either Busulfan/Cyclophosphamide or Treosulfan/Fludarabin. Either HLA-identical siblings or matched-unrelated donors with not more than one mismatch were allowed. ATG was mandatory in mismatched or unrelated transplantation. Progression-free survival (PFS) was 62% and overall survival (OS) was 68% after 16.5-year follow-up. Significant differences in PFS and OS between both trials were not observed. Patients below 56 years and patients after myeloablative conditioning had a better outcome compared to patients of the corresponding groups. Nine patients have died between day +8 and 5.9 years after SCT. Data from 7 long-term surviving patients showed an excellent Quality-of-life (QoL) after alloSCT. AlloSCT for MCL delivers excellent long-term survival data. The early mortality is higher than after autoSCT; however, the survival curves after alloSCT indicate the curative potential of this therapy. AlloSCT is a standard of care for all feasible patients with refractory or relapsed MCL and should offer to selected patients with de novo MCL and a poor risk profile. For defining the position of alloSCT in the therapeutic algorithm of MCL therapy, a randomized comparison of autoSCT and alloSCT is mandatory.

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.

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.

Proapoptotic protein BIM as a novel prognostic marker in mantle cell lymphoma

Mantle cell lymphoma (MCL) is an aggressive B-cell lymphoma. Numerous studies have demonstrated many genetic aberrations in MCL in addition to the characteristic t(11:14), including frequent biallelic deletions of Bim, a proapoptotic member of the BCL-2 family. In mice, Bim deletion coupled with cyclin D1 overexpression generates pathologic and molecular features of human MCL. Since the regulation of apoptosis is crucial in MCL pathogenesis, we hypothesize that BIM expression may be associated with tumor cell survival. Clinical data and tissue from 100 nodal MCL cases between 1988 and 2009 were collected from three large academic medical centers. The average patient age of our MCL cohort was 65.5 years old (range, 42-97) with a 2:1 male to female ratio. Immunohistochemistry was performed with a validated anti-BIM antibody. Patients were separated into low and high BIM-expressing categories with a cutoff of 80%. As expected for a proapoptotic tumor suppressor, patients with high BIM expression were less likely to have progressive disease and more likely to have a complete response (P = .022). In addition, high BIM-expressing MCL tumors revealed a trend toward increased overall survival with this trend persisting in sub-analysis of Ann Arbor stages III and IV. No correlation between BIM expression, Ki-67 index, and MIPI score was observed, suggesting a role for BIM as a novel independent prognostic factor. While BIM is only one member of a complex family of apoptosis-regulating proteins, these findings may yield clinically relevant information for the prognosis and therapeutic susceptibility of MCL.

Long-Term Follow-Up of 90Y-Ibritumomab Tiuxetan, Fludarabine, and Total Body Irradiation-Based Nonmyeloablative Allogeneic Transplant Conditioning for Persistent High-Risk B Cell Lymphoma

Nonmyeloablative allogeneic hematopoietic cell transplantation (HCT) can provide prolonged remissions in patients with advanced B cell lymphoma (B-NHL) via the graft-versus-lymphoma effect, although inferior results are seen in patients with chemoresistant, bulky, or aggressive disease. Radioimmunotherapy can safely induce responses in B-NHL with minimal nonhematologic toxicity. Initial results of 90Y-ibritumomab tiuxetan-based allografting demonstrated early safety and disease control in nonremission patients but with short follow-up. Here we report the long-term outcomes of patients treated on this study with specific emphasis on patients achieving early remissions. Eleven of 40 patients were alive at a median follow-up of 9 years (range, 5.3 to 10.2). Fourteen (35%) deaths were due to disease progression and 14 (35%) deaths to complications from HCT. One patient died of a Merkel cell carcinoma. The 5-year overall and progression-free survival for patients with indolent B-NHL was 40% and 27.5%, respectively. None of the patients with diffuse large B cell lymphoma was a long-term disease-free survivor regardless of early remission status. 90Y-ibritumomab tiuxetan-based allografting represents a viable option in patients with indolent histologies. Improved strategies are needed for aggressive B-NHL. The original trial was registered at www.clinicaltrials.gov as NCT00119392.

Mantle cell lymphoma with late onset gyrus-like colorectal infiltration: A rare case and literature review

Mantle cell lymphoma (MCL), characterized by t (11; 14) (q13; q32) translocation and cyclin D1 overexpression, is still a challenging subtype of non-Hodgkin's lymphoma. The majority of MCL cases are discovered in male elderly people and in advanced stages with extranodal infiltration especially the gastrointestinal tract. Multiple lymphomatous polyposis is a typical manifestation of MCL infiltrating the gastrointestinal tract, and the colon is the most commonly involved site. In this paper, we report a case of MCL with late onset colorectal infiltration in a 53-year-old female patient presenting with gyrus-like thickened mucosal folds instead of multiple polyps as revealed by colonoscopic examination. Remarkably, the patient developed colorectal infiltration presenting with intermittent bloody stool after being diagnosed with classical MCL for two years and treated with several cycles of combined chemotherapy. Immunohistochemical staining showed that the lymphoid infiltrate in the colorectal mucosa was positive for cyclin D1, CD5, CD19, CD20, CD21, CD43, CD79a, Bcl-2, PAX-5, and SOX11 (scattered), but negative for CD2, CD3, CD7, CD10, CD23, Bcl-6, c-myc, and Mum-1. The Ki-67 proliferation index was around 15%.

Current Approaches to Mantle Cell Lymphoma: Diagnosis, Prognosis, and Therapies

Mantle cell lymphoma (MCL) is a unique lymphoma subtype, both biologically and clinically. Virtually all cases are characterized by a common genetic lesion, t(11;14), resulting in overexpression of cyclin D1. The clinical course is moderately aggressive, and the disease is considered incurable. Considerable biologic and clinical heterogeneity exists, with some patients experiencing a rapidly progressive course, while others have disease that is readily managed. New tools exist for risk stratification and may allow for a more personalized approach in the future. Landmark studies have been completed in recent years and outcomes appear to be improving. Randomized clinical trials have clarified the role of high-dose cytarabine (Ara-C) for younger patients and have demonstrated a role for maintenance rituximab therapy. Multiple areas of uncertainty remain, however, and are the focus of ongoing research. This review focuses on (1) strategies to differentiate between aggressive and less aggressive cases, (2) understanding who should receive hematopoietic stem cell transplantation, and (3) the role for maintenance therapy in MCL.

A Review of Myeloablative vs Reduced Intensity/Non-Myeloablative Regimens in Allogeneic Hematopoietic Stem Cell Transplantations

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is a curative treatment option for both malignant and some benign hematological diseases. During the last decade, many of the newer high-dose regimens in different intensity have been developed specifically for patients with hematologic malignancies and solid tumors. Today there are three main approaches used prior to allogeneic transplantation: Myeloablative (MA), Reduced Intensity Conditioning (RIC) and Non-MA (NMA) regimens. MA regimens cause irreversible cytopenia and there is a requirement for stem cell support. Patients who receive NMA regimen have minimal cytopenia and this type of regimen can be given without stem cell support. RIC regimens do not fit the criteria of MA and NMA: the cytopenia is reversible and the stem cell support is necessary. NMA/RIC for Allo-HSCT has opened a new era for treating elderly patients and those with comorbidities. The RIC conditioning was used for 40% of all Allo-HSCT and this trend continue to increase. In this paper, we will review these regimens in the setting of especially allogeneic HSCT and our aim is to describe the history, features and impact of these conditioning regimens on specific diseases.

Indian Council of Medical Research Consensus Document for the Management of Non-Hodgkin's Lymphoma (High Grade)

This consensus document is based on the guidelines related to the management of Non Hodgkin's Lymphoma (High grade) in the Indian population as proposed by the core expert committee. Accurate diagnosis in hematolymphoid neoplasm requires a combination of detailed history,clinical examination, and various investigations including routine laboratory tests, good quality histology section (of tumor and also bone marrow aspirate/biopsy), immunostaining, cytogenetic and molecular studies and radiology investigations. The staging system used for adult high grade lymphomas is based on the Ann Arbor system and includes various parameters like clinical, haematology, biochemistry, serology and radiology. Response should be evaluated with radiological evaluation after 3-4 cycles and at the end of treatment based on criteria including and excluding PET. Treatment of high grade lymphomas is based on histologic subtype, extent of disease, and age of the patient. Autologous stem cell transplantation after high dose chemotherapy is effective in the treatment of relapsed NHL. Newer RT techniques like 3 dimensional conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) can significantly reduce radiation doses to surrounding normal tissues in lymphoma patients. Patients should be followed up every 3 to 4 months for the first 2 years, followed by 6 monthly for the next 3 years and then annually.

Reduced-intensity or myeloablative allogeneic hematopoietic cell transplantation for mantle cell lymphoma: a systematic review

Allogeneic hematopoietic cell transplantation (allo-HCT) is the only known treatment that can offer a cure in mantle cell lymphoma, but it is unclear if regimen dose-intensity offers any advantage. We performed a systematic review/meta-analysis to assess efficacy of allo-HCT using myeloablative or reduced-intensity conditioning. We report results according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. On the basis of a relatively lower nonrelapse mortality and a slightly better progression-free survival/event-free survival and overall survival rates, reduced-intensity allo-HCT regimens appear to be the preferred choice when an allo-HCT is being considered for mantle cell lymphoma. The higher rate of relapse when offering reduced-intensity regimens cannot be ignored but certainly highlights opportunities to incorporate post-transplant strategies to mitigate this risk. A prospective comparative study is ultimately needed to generate more conclusive evidence.

Clinical outcomes of a novel combination of lenalidomide and rituximab followed by stem cell transplantation for relapsed/refractory aggressive B-cell non-hodgkin lymphoma

We retrospectively compared outcomes of patients with relapsed/refractory non-Hodgkin lymphoma (NHL) who underwent stem cell transplantation (SCT) with stable disease or better following a novel combination of lenalidomide and rituximab (LR) treatment and did not undergo SCT in a phase I/II clinical trial. We retrospectively compared outcomes of patients who underwent SCT with that of patients who had stable disease or better following LR treatment and did not undergo SCT. Twenty-two patients enrolled in LR clinical trial and undergone SCT were identified, 13 with mantle cell lymphoma (MCL) and nine with large B-cell lymphoma (LBCL). All patients who underwent SCT achieved complete response. In the MCL subset, there were no significant differences between SCT and non-SCT groups except that non-SCT patients were older and had a higher mantle-cell international prognostic index score. There was no difference between SCT-group and non-SCT-group in response duration (P=0.3), progression-free survival (PFS) (P=0.304) and overall survival (OS) (P=0.87). In LBCL subgroup, there were no significant differences between two groups except that non-SCT group had a higher international prognostic index score. Patients with LBCL who underwent SCT had significantly longer response duration (P=0.001), PFS (P=0.000), and OS (P=0.003) than the non-SCT group. The novel therapeutic combination offers a bridge to SCT in patients with relapsed/refractory aggressive B-cell NHL.

Long-term sustained disease control in patients with mantle cell lymphoma with or without active disease after treatment with allogeneic hematopoietic cell transplantation after nonmyeloablative conditioning

BACKGROUND

Previously, early results were reported for allogeneic hematopoietic cell transplantation (HCT) after nonmyeloablative conditioning with 2 Gy of total body irradiation with or without fludarabine and/or rituximab in 33 patients with mantle cell lymphoma (MCL).

METHODS

This study examined the outcomes of 70 patients with MCL and included extended follow-up (median, 10 years) for the 33 initial patients. Grafts were obtained from human leukocyte antigen (HLA)-matched, related donors (47%), unrelated donors (41%), and HLA antigen-mismatched donors (11%).

RESULTS

The 5-year incidence of nonrelapse mortality was 28%. The relapse rate was 26%. The 5-year rates of overall survival (OS) and progression-free survival (PFS) were 55% and 46%, respectively. The 10-year rates of OS and PFS were 44% and 41%, respectively. Eighty percent of surviving patients were off immunosuppression at the last follow-up. The presence of relapsed or refractory disease at the time of HCT predicted a higher rate of relapse (hazard ratio [HR], 2.94; P = .05). Despite this, OS rates at 5 (51% vs 58%) and 10 years (43% vs 45%) were comparable between those with relapsed/refractory disease and those undergoing transplantation with partial or complete remission. A high-risk cytomegalovirus (CMV) status was the only independent predictor of worse OS (HR, 2.32; P = .02). A high-risk CMV status and a low CD3 dose predicted PFS (HR, 2.22; P = .03).

CONCLUSIONS

Nonmyeloablative allogeneic HCT provides a long-term survival benefit for patients with relapsed MCL, including those with refractory disease or multiple relapses.

Treatment strategies in mantle cell lymphoma

Mantle cell lymphoma (MCL) is a distinct B-cell non-Hodgkin's lymphoma (NHL) defined by the translocation t(11;14). MCL combines characteristics of both indolent and aggressive lymphomas, and it is incurable with conventional chemoimmunotherapy but has a more aggressive disease course. Minimal data exist on treatment of patients diagnosed with early-stage disease (stage I-II non-bulky), as this represents only a small portion of the patients diagnosed with MCL, but therapeutic options evaluated in retrospective studies include radiation or combination radiation and chemotherapy. There is a subset of patients with newly diagnosed MCL that can be observed without treatment, but the majority of patients will require treatment at diagnosis. Treatment is often based on age (≤65-70 years of age), comorbidities, and risk factors for disease. The majority of patients who are younger and without significant comorbidities are treated with intensive induction using combination chemoimmunotherapy regimens, many which include consolidation with autologous stem cell transplant (ASCT). Several regimens have been studied that show improved median progression-free survival (PFS) to 3-6 years in this population of patients. The majority of older patients (≥65-70 years of age) are treated with combination chemoimmunotherapy regimens with consideration of rituximab maintenance, with enrollment on a clinical trial encouraged. Therapy for relapsed disease is dependent on prior treatment, age, comorbidities, and toxicities but includes targeted therapies such as the Bruton's tyrosine kinase (BTK) inhibitor ibrutinib, the immunomodulatory agent lenalidomide, the proteasome inhibitor bortezomib, combination chemoimmunotherapy, ASCT, and allogeneic stem cell transplant in selected cases. Several novel agents and targeted therapies alone or in combination are currently being studied and developed in both the upfront and relapsed setting.

Allogeneic Hematopoietic Stem Cell Transplantation in Mantle Cell Lymphoma: A Retrospective Analysis of 7 Patients

Mantle cell lymphoma (MCL) is a B cell non-Hodgkin's lymphoma characterized by a poor prognosis. Many different therapeutic approaches including intensive chemotherapy as well as new targeted therapies are established. However, overall survival remains unsatisfying. As the sole curative option, allogeneic hematopoietic stem cell transplantation (HSCT) has been described, but only a limited number of patients qualify for this procedure. We have retrospectively analyzed 7 patients with stage IV MCL undergoing allogeneic HSCT at our institution. A myeloablative regimen was used in 1 patient, while the other 6 patients received reduced-intensity conditioning. Four patients had an HLA-identical sibling, and the remaining 3 patients had an HLA-identical unrelated donor. One patient developed acute graft-versus-host disease (skin, grade III; intestine, grade II). Two patients died from transplant-related causes, 3 patients died due to progressive disease and the remaining 2 patients are still in complete remission 147 and 8 months after transplantation. Allogeneic HSCT offers a therapeutic treatment option for selected patients in a relapsed/refractory setting. The incorporation of novel agents has improved the outcome of patients with MCL. Thus, the role and optimal time point of allogeneic HSCT should be reevaluated in randomized trials.

Role of allogeneic stem cell transplantation in mantle cell lymphoma

Despite a wide spectrum of treatment options, mantle cell lymphoma (MCL) remains a challenging hematologic malignancy to manage. Advances in front-line therapy, including the monoclonal antibody rituximab and increasing use of cytarabine, have improved remission rates. Autologous hematopoietic cell transplantation (HCT) can effectively consolidate remission of MCL, leading to encouraging survival beyond 5 yr. However, nearly all patients with MCL will relapse and require salvage therapy. Novel agents such as ibrutinib, bortezomib, and lenalidomide have dramatically expanded the options for treating relapsed MCL. In this review, we summarize the clinical evidence supporting the use of allogeneic donor HCT in MCL and make recommendations on indications for its use. Data suggest that allogeneic donor HCT is the only curative therapy for patients with poor prognosis or aggressive MCL. Patient selection, timing, and optimal use remain a matter of scientific debate and given the rapidly changing therapeutic landscape of MCL, the outcomes of allogeneic HCT should be interpreted in the context of novel therapeutics.

Mantle cell lymphoma: observation to transplantation

Mantle cell lymphoma as a rare non-Hodgkin B-cell lymphoma can present in different clinical presentations such as an aggressive form or a more indolent picture. Treatment modality is based on multiple factors including age, presence or absence of symptoms, and comorbidities. Watchful waiting is a reasonable approach for asymptomatic patients especially in elderly. In symptomatic patients, treatment is chemo-immunotherapy followed by maintenance immunotherapy or autologous bone marrow transplant. Allogeneic bone marrow transplant has a potential benefit of cure for relapsed/refractory cases, but it has a high mortality rate. Novel treatment with agents such as ibrutinib, a Bruton tyrosine kinase inhibitor, has shown promising results in relapse/refractory cases. We extensively review the most recent data on diagnostic and therapeutic management of mantle cell lymphoma through presenting two extreme clinical scenarios.

Mantle cell lymphoma: evolving management strategies

Mantle cell lymphoma (MCL) is a rare and aggressive form of non-Hodgkin's lymphoma that generally affects older individuals and continues to have one of the worst outcomes of all the lymphomas. Over the last decade, there has been a widespread adoption of cytarabine-based therapy in younger patients, and the incorporation of rituximab into chemotherapeutic regimens has become an evidence-based standard of care. However MCL remains a largely incurable disease, and following relapse, it can be a challenge to manage. Although it is possible to define prognosis reliably, there are, as yet, no clear diagnostic or response-adjusted parameters that can help to guide therapeutic decisions. However, there are a number of highly active targeted therapies that are moving into the clinic that are set to transform the therapeutic paradigm for this disease in the very near future. This review will explore the molecular pathogenesis of MCL and the current and evolving therapeutic strategies for this disease.

The EBMT/EMCL consensus project on the role of autologous and allogeneic stem cell transplantation in mantle cell lymphoma

The role of both autologous (autoSCT) and allogeneic stem cell transplantation (alloSCT) in the management of mantle cell lymphoma (MCL) remains to be clarified. We conducted a consensus project using the RAND-modified Delphi consensus procedure to provide guidance on how SCT should be used in MCL. With regard to autoSCT, there was consensus in support of: autoSCT is the standard first-line consolidation therapy; induction therapy should include high-dose cytarabine and Rituximab; complete or partial remission should be achieved before autoSCT; Rituximab maintenance following autoSCT is not indicated; and omission of autoSCT in 'low-risk' patients is not indicated. No consensus could be reached regarding: autoSCT in the treatment of relapsed disease following non-transplant therapy; the value of positron emission tomography scanning and minimal residual disease (MRD) monitoring; in vivo purging with Rituximab; total body irradiation conditioning for autoSCT; and preemptive Rituximab after autoSCT. For alloSCT, consensus was reached in support of: alloSCT should be considered for patients relapsing after autoSCT; reduced intensity conditioning regimens should be used; allogeneic immunotherapy should be used for MRD eradication after alloSCT; and there is a lack of prognostic criteria to guide the use of alloSCT as first-line consolidation. No consensus was reached regarding the role of alloSCT for relapsed disease following non-transplant therapy.

Bendamustine as salvage treatment for patients with relapsed or refractory mantle cell lymphoma patients: a retrospective study of the Spanish experience

Patients with mantle cell lymphoma (MCL) have an adverse outcome after relapse. Bendamustine has demonstrated a good efficacy and toxicity profile in previously reported trials. In this study, we present a retrospective analysis of the Spanish experience in relapsed/refractory MCL treated with bendamustine in combination or alone with the objective of knowing the efficacy and toxicity profile of this treatment in our current clinical practice. Fifty eight patients were registered: 67 % male with median age of 71 years, and 2 is the median number of previous lines. The most frequent bendamustine regimen was bendamustine plus rituximab (83 %). The median number of cycles was 5 (range 1-8). The overall response rate was 84 % with 53 % of complete response/unconfirmed complete response (CR/uCR). Median progression-free survival (PFS) was 16 months (95 % confidence interval (CI) 13.3-18.8), and for patients who achieved CR/uCR, it was 33 months (95 % CI 11.1-54.2). Median overall survival (OS) was 30 months (95 % CI 25.6-34.9). For PFS, only blastoid histology and not achieving CR after bendamustine had a significant negative impact on the univariate and multivariate analyses (p < 0.05). Nevertheless, for OS, only an elevated lactate dehydrogenase (LDH) had negative impact on both, univariate and multivariate analyses (p < 0.05). Only one case of treatment-related mortality in a 79-year-old patient with very bad performance status was reported. In 280 cycles, 12 (4 %) hospitalizations for febrile neutropenia were reported. In our population, bendamustine has been a good salvage treatment with a favorable toxicity profile in a non selected and heavily pretreated population of patients with MCL.

Risk factors for etiology and prognosis of mantle cell lymphoma

Non-Hodgkin lymphomas (NHLs) include any kind of lymphoma except Hodgkin's lymphoma. Mantle cell lymphoma (MCL) is a B-cell NHL and it accounts for about 6% of all NHL cases. Its epidemiologic and clinical features, as well as biomarkers, can differ from those of other NHL subtypes. This article first provides a very brief description of MCL's epidemiology and clinical features. For etiology and prognosis separately, we review clinical, environmental, and molecular risk factors that have been suggested in the literature. Among a large number of potential risk factors, only a few have been independently validated, and their clinical utilization has been limited. More data need to be accumulated and effectively analyzed before clinically useful risk factors can be identified and used for prevention, diagnosis, prediction of prognosis path, and treatment selection.

Management of relapsed/refractory mantle cell lymphoma: a review of current therapeutic strategies

Abstract Despite recent advances in therapeutic strategies, a large proportion of patients with mantle cell lymphoma (MCL) experience progression after first-line treatment. Several attempts have been made to assess the role of different therapies for the treatment of patients with relapsed/refractory mantle cell lymphoma; however, a consensus on the optimal therapeutic strategy for each individual patient has not been reached. Overall, clinical evidence from phase II studies shows that high-dose cytarabine containing regimens, stem cell transplant and different biological agents all have promising activity with acceptable safety profiles. Therefore, these therapies can represent suitable treatment options for patients with relapsed/refractory MCL. Among different biological agents, at present only temsirolimus has been tested in a phase III study. This review considers available evidence on the management of relapsed/refractory MCL as discussed during a consensus meeting on the current treatment strategies for MCL.

Alternative donor hematopoietic stem cell transplantation for mature lymphoid malignancies after reduced-intensity conditioning regimen: similar outcomes with umbilical cord blood and unrelated donor peripheral blood

We have reported encouraging results of unrelated cord blood transplantation for patients with lymphoid malignancies. Whether those outcomes are comparable to matched unrelated donor transplants remains to be defined. We studied 645 adult patients with mature lymphoid malignancies who received an allogeneic unrelated donor transplant using umbilical cord blood (n=104) or mobilized peripheral blood stem cells (n=541) after a reduced-intensity conditioning regimen. Unrelated cord blood recipients had more refractory disease. Median follow-up time was 30 months. Neutrophil engraftment (81% vs. 97%, respectively; P<0.0001) and chronic graft-versus-host disease (26% vs. 52%; P=0.0005) were less frequent after unrelated cord blood than after matched unrelated donor, whereas no differences were observed in grade II-IV acute graft-versus-host disease (29% vs. 32%), non-relapse mortality (29% vs. 28%), and relapse or progression (28% vs. 35%) at 36 months. There were also no significant differences in 2-year progression-free survival (43% vs. 58%, respectively) and overall survival (36% vs. 51%) at 36 months. In a multivariate analysis, no differences were observed in the outcomes between the two stem cell sources except for a higher risk of neutrophil engraftment (hazard ratio=2.12; P<0.0001) and chronic graft-versus-host disease (hazard ratio 2.10; P=0.0002) after matched unrelated donor transplant. In conclusion, there was no difference in final outcomes after transplantation between umbilical cord blood and matched unrelated donor transplant. Umbilical cord blood is a valuable alternative for patients with lymphoid malignancies lacking an HLA-matched donor, being associated with lower risk of chronic graft-versus-host disease.

Immunotherapy with FBTA05 (Bi20), a trifunctional bispecific anti-CD3 x anti-CD20 antibody and donor lymphocyte infusion (DLI) in relapsed or refractory B-cell lymphoma after allogeneic stem cell transplantation: study protocol of an investigator-driven, open-label, non-randomized, uncontrolled, dose-escalating Phase I/II-trial

Background

Patients with B cell malignancies refractory to allogeneic stem cell transplantation (SCT) can be treated by subsequent immunotherapy with donor lymphocyte infusions (DLI). But unlike myeloid leukemia, B cell leukemia and lymphoma are less sensitive to allogeneic adoptive immunotherapy. Moreover, the beneficial graft-versus-lymphoma (GVL) effect may be associated with moderate to severe graft-versus-host disease (GVHD). Thus, novel therapeutic approaches augmenting the anti-tumor efficacy of DLI and dissociating the GVL effect from GVHD are needed. The anti-CD20 x anti-CD3 trifunctional bispecific antibody (trAb) FBTA05 may improve the targeting of tumor cells by redirecting immune allogeneic effector cells while reducing the risk of undesirable reactivity against normal host cells. Hence, FBTA05 may maximize GVL effects by simultaneously decreasing the incidence and severity of GVHD.

Methods/Design

Based on this underlying treatment concept and on promising data taken from preclinical results and a small pilot study, an open-label, non-randomized, uncontrolled, dose-escalating phase I/II-study is conducted to evaluate safety and preliminary efficacy of the investigational antibody FBTA05 in combination with DLI for patients suffering from rituximab- and/or alemtuzumab-refractory, CD20-positive low- or high-grade lymphoma after allogeneic SCT. During the first trial phase with emphasis on dose escalation a maximum of 24 patients distributed into 4 cohorts will be enrolled. For the evaluation of preliminary efficacy data a maximum of 12 patients (6 patients with low-grade lymphoma and/or Chronic Lymphocytic Leukemia (CLL) / 6 patients with high-grade or aggressive lymphoma) will attend the second phase of this clinical trial.

Discussion

Promising data (e.g. induction of cellular immunity; GVL predominance over GVHD; achievement of partial or complete responses; prolongation of time-to-progression) obtained from this phase I/II trial would represent the first milestone in the clinical evaluation of a novel immunotherapeutic concept for treatment-resistant low- and high-grade lymphoma and NHL patients in relapse.

Trial registration

NCT01138579

Clinical practice guidelines for diagnosis, treatment, and follow-up of patients with mantle cell lymphoma. Recommendations from the GEL/TAMO Spanish Cooperative Group

Mantle cell lymphoma (MCL) is considered a distinct type of B-cell lymphoma genetically characterized by the t(11;14) translocation and cyclin D1 overexpression. There is also a small subset of tumors negative for cyclin D1 expression that are morphologically and immunophenotypically indistinguishable from conventional MCL. Although in the last decades, the median overall survival of patients with MCL has improved significantly, it is still considered as one of the poorest prognoses diseases among B-cell lymphomas. Election of treatment for patients with MCL is complex due to the scarcity of solid evidence. Current available data shows that conventional chemotherapy does not yield satisfactory results as in other types of B-cell lymphomas. However, the role of other approaches such as autologous or allogenic stem cell transplantation, immunotherapy, the administration of consolidation or maintenance schedules, or the use of targeted therapies still lack clear indications. In view of this situation, the Spanish Group of Lymphomas/Autologous Bone Marrow Transplantation has conducted a series of reviews on different aspects of MCL, namely its diagnosis, prognosis, first-line and salvage treatment (both in young and elderly patients), new targeted therapies, and detection of minimal residual disease. On the basis of the available evidence, a series of recommendations have been issued with the intention of providing guidance to clinicians on the diagnosis, treatment, and monitoring of patients with MCL.

Allogeneic hematopoietic cell transplantation for diffuse large B cell lymphoma: who, when and how?

Despite overall improvements in outcomes of patients with diffuse large B cell lymphoma (DLBCL), ∼30-40% of patients develop relapsed or refractory disease. For patients with chemo refractory disease, or recurrent disease following autologous hematopoietic SCT (auto-HCT), the prognosis is poor, with no consensus on the optimal therapy. Currently, owing to the graft vs lymphoma effect, hematopoietic allogeneic hematopoietic cell transplantation (allo-HCT) is the only potentially curative option for such patients. In addition, many patients who are considered today for auto-HCT actually have a low likelihood of benefit. For example, a patient with prior rituximab exposure who relapses within 1 year of diagnosis and has a second-line age-adjusted International Prognosis Index of 2 or 3 at relapse has a <25% chance of being cured by auto-HCT. It is possible that such patients may be better served with an allo-HCT. Unfortunately, in many cases, allo-HCT applicability is limited by patient age, comorbidities, performance status and treatment-related toxicities. Recent attempts to improve the efficacy of auto-HCT, such as incorporating radio-immunotherapy into the conditioning regimen, have not resulted in improved outcomes. However, incorporation of novel agents such as anti-programmed death-1 antibodies as maintenance therapy after auto-HCT show promise. Allo-HCT in relapsed/refractory DLBCL patients can result in a 30-40% PFS rate at 3 years, in part due to a graft vs DLBCL effect. While reduced-intensity/non-myeloablative conditioning is increasingly being used, certain patients may benefit from myeloablative conditioning. We present an algorithm intended to discriminate which relapsed and refractory DLBCL patients are most likely to benefit from auto-HCT vs allo-HCT. New approaches, using novel agents that target the molecular heterogeneity in DLBCL, will be an essential component of moving the field forward. Lastly, we propose a prospective registry-based study as the only feasible mechanism to define the optimal position of allo-HCT in the overall treatment strategy for DLBCL. It is hoped that this review will promote the development of prospective multicenter efforts to determine whether such patients do, in fact, benefit from earlier and/or more effective implementation of allo-HCT.

Reduced-intensity conditioning allogeneic stem cell transplantation in malignant lymphoma: current status

Allogeneic stem cell transplantation (allo-SCT) is a potential cure for patients with malignant lymphoma that is based on the graft-versus-lymphoma (GVL) effect. Myeloablative conditioning allo-SCT is associated with high mortality and morbidity, particularly in patients older than 45 years, heavily pretreated patients (prior hematopoietic stem cell transplantation or more than two lines of conventional chemotherapy) or patients affected by other comorbidities. Therefore, conventional allo-SCT is restricted to younger patients (<50 to 55 years) in good physical condition. Over the last decade, allo-SCT with reduced-intensity conditioning (RIC-allo-SCT) has been increasingly used to treat patients with lymphoma. This treatment is associated with lower toxicity and substantial decrease in the incidence of transplant-related mortality, and has the potential to lead to long-term remissions. Therefore, patients who are not suitable to undergo conventional allo-SCT can benefit from the potentially curative GVL effects of allo-SCT. Although RIC-allo-SCT has improved the survival of lymphoma patients, high post-transplant relapse rates or disease progression mainly results in treatment failure. Thus, further improvement is clearly needed. The role and timing of RIC-allo-SCT in the treatment of lymphoma remains unclear. Therefore, more prospective studies should clarify the effectiveness of this method. In this article, we review the recent literature on RIC-allo-SCT as a treatment for major lymphoma subtypes. Areas that require further investigation in the context of clinical trials are also highlighted.

Promising role of reduced-toxicity hematopoietic stem cell transplantation (PART-I)

Allogeneic hematopoietic stem cell transplantation (HSCT) remains a potential curative option for many patients with hematological malignancies (HM). However, the high rate of transplantation-related mortality (TRM) restricted the use of standard myeloablative HSCT to a minority of young and fit patients. Over the past few years, it has become evident that the alloreactivity of the immunocompetent donor cells mediated anti-malignancy effects independent of the action of high dose chemoradiotherapy. The use of reduced intensity conditioning (RIC) regimens has allowed a graft-versus-malignancy (GvM) effect to be exploited in patients who were previously ineligible for HSCT on the grounds of age and comorbidity. Retrospective analysis showed that RIC has been associated with lower TRM but a higher relapse rate leading to similar intermediate term overall and progression-free survivals when compared to standard myeloablative HSCT. However, the long term antitumor effect of this approach is less well established. Prospective studies are ongoing to define which patients might most benefit from reduced toxicity stem cell transplant (RT-SCT) and which transplant protocols are suitable for the different types of HM. The advent of RT-SCT permits the delivery of a potentially curative GvM effect to the majority of patients with HM whose outcome with conventional chemotherapy would be dismal. Remaining challenges include development of effective strategies to reduce relapse rates by augmenting GvM effects without increasing toxicity.

Long-Term Results of Fludarabine/Melphalan as a Reduced-Intensity Conditioning Regimen in Mantle Cell Lymphoma: The GELTAMO Experience

BACKGROUND

We herein report the long-term results of an allogeneic reduced-intensity conditioning (allo-RIC) protocol used in 21 consecutive patients (16 males, median age 56 years, 71% in complete remission) diagnosed with mantle cell lymphoma (MCL).

METHODS

The allo-RIC consisted of fludarabine plus melphalan and peripheral blood hematopoietic stem cells (PBSCs) from human leukocyte antigen (HLA)-identical siblings were used in all cases. Median CD34+ infused cells was 5.8 times 10(6)/kg. All patients engrafted promptly.

RESULTS

Early toxicity included mild/moderate mucositis (43%), febrile neutropenia (33%) and bacterial infections (19%). With a median follow up of 48 months, four deaths were reported, all due to infections and/or graft-versus-host disease (GVHD), yielding a 3-year cumulative incidence of nonrelapse mortality of 19.5%. Grade III-IV acute GVHD occurred in 15% and chronic GVHD in 78%, being extensive in 39%. The 5-year progression-free survival (PFS) and overall survival (OS) were both 80% (95% CI: 63-97%). Age was the only possible prognostic factor for OS, which was 43% for those aged more than 60 years and 100% for those younger (p < 0.001).

CONCLUSIONS

Our data confirm that allo-RIC offers a low toxicity profile and a chance for prolonged long-term disease-free survival in MCL, particularly in younger patients.

Nonmyeloablative allogeneic stem cell transplantation for non-hodgkin lymphoma

Non-Hodgkin lymphomas constitute a heterogeneous group of hematologic malignancies with varying aggressiveness and many therapeutic options. Nonmyeloablative (NMA) conditioning has been the cornerstone of allogeneic adoptive immunotherapy for these diseases. This approach utilizes a reduced intensity preparative regimen to achieve engraftment with little toxicity. This allows for development of the immune graft-versus-lymphoma effect. Results depend on the histologic type of lymphoma, prognostic factors, patient characteristics, and chemosensitivity. For follicular lymphomas, NMA transplants are highly effective in patients with refractory or recurrent disease after the best chemoimmunotherapy available and who have a matched sibling or unrelated donor. In mantle cell lymphoma, autologous stem cell transplants are generally ineffective for patients with recurrent disease; we reported 6-year actuarial progression-free survival rate of 46%, using NMA allogeneic transplants. The indications of NMA transplants for diffuse large B-cell lymphoma and T-cell lymphomas are controversial; success has been reported in selected high-risk patients and those relapsing after an autologous transplantation who have chemosensitive disease. Considerations for the conditioning regimen, donor source, graft-versus-host disease prophylaxis, donor lymphocyte infusion, and relapse prevention methods are reviewed.

ESMO Consensus conferences: guidelines on malignant lymphoma. part 2: marginal zone lymphoma, mantle cell lymphoma, peripheral T-cell lymphoma

To complement the existing treatment guidelines for all tumour types, ESMO organizes consensus conferences to focus on specific issues in each type of tumour. In this setting, a consensus conference on the management of lymphoma was held on 18 June 2011 in Lugano, next to the 11th International Conference on Malignant Lymphoma. The conference convened ∼30 experts from all around Europe, and selected six lymphoma entities to be addressed; for each of them, three to five open questions were to be addressed by the experts. For each question, a recommendation should be given by the panel, referring to the strength of the recommendation based on the level of evidence. This consensus report focuses on the three less common lymphoproliferative malignancies: marginal zone lymphoma, mantle cell lymphoma, and peripheral T-cell lymphomas. A first report had focused on diffuse large B-cell lymphoma, follicular lymphoma, and chronic lymphocytic leukaemia.

Mechanism of the antitumoral activity of deferasirox, an iron chelation agent, on mantle cell lymphoma

Mantle cell lymphoma (MCL) characterized by the t(11;14)(q13;q32) translocation, resulting in cyclin D1 overexpression, is one of the most challenging lymphomas to treat. Iron chelators, such as deferasirox, have previously been shown to exhibit anti-proliferative properties; however, their effect on MCL cells has never been investigated. We showed that deferasirox exhibited antitumoral activity against the MCL cell lines HBL-2, Granta-519 and Jeko-1, with 50% inhibitory concentration (IC(50)) values of 7.99 ± 2.46 μM, 8.93 ± 2.25 μM and 31.86 ± 7.26 μM, respectively. Deferasirox induced apoptosis mediated through caspase-3 activation and decreased cyclin D1 protein levels resulting from increased proteasomal degradation. We also demonstrated down-regulation of phosphor-RB (Ser780) expression, which resulted in increasing levels of the E2F/RB complex and G(1)/S arrest. Finally, we showed that deferasirox activity was dependent on its iron chelating ability. The present data indicate that deferasirox, by down-regulating cyclin D1 and inhibiting its related signals, may constitute a promising adjuvant therapeutic molecule in the strategy for MCL treatment.

Reduced-intensity hematopoietic stem cell transplants for malignancies: harnessing the graft-versus-tumor effect

Allogeneic hematopoietic cell transplantation combines the power of cytotoxic chemo/radiotherapy with the ability of the new immune system to seek out and destroy tumor cells. However, administration of such myeloablative transplants is fraught with risks, some of which are related to the intensive conditioning regimens. Reductions in the intensity of the administered cytotoxic therapy have demonstrated that under some circumstances, the burden of fighting tumor and enhancing stem cell engraftment can be shouldered mostly by the transplanted immune system. Reduced intensity has allowed a potentially curative therapy for hematologic malignancies to be offered to an expanded patient population. Ongoing research seeks to enhance the safety and power of this form of allogeneic immunotherapy.

Allogeneic hematopoietic cell transplantation in mantle cell lymphoma

Mantle cell lymphoma (MCL) is a high-risk non-Hodgkin lymphoma that is considered incurable with standard chemotherapy. While autologous hematopoietic cell transplantation (autoHCT) can provide lengthy disease-free survival in select patients, cure generally is not an expected outcome with this approach. Allogeneic hematopoietic cell transplantation (alloHCT), which can exploit the potential benefits of graft-versus-lymphoma (GVL) effect, has been shown in multiple studies to yield a small but reproducible portion of patients with long-term remission more suggestive of cure. Historically, alloHCT for MCL was administered after myeloablative conditioning, but this approach was limited by early non-relapse mortality. Development of reduced-intensity (RI)-alloHCT has abrogated some of the early post-transplant risks, allowing this potentially effective therapy to be offered to a larger number of affected individuals. The trends in published data reflect a preference toward using RI-alloHCT for MCL, often because patients in whom alloHCT is being considered have relapsed disease following myeloablative autoHCT. Further efforts to spare the effects of graft-versus-host disease (GVHD) while still evoking GVL remain a focus of investigation in this area. In this review, we will discuss the application of alloHCT in the management of MCL, the factors associated with outcome, the different methods in which it can be performed, and the strategies that can be employed in post-alloHCT relapse.

Reduced-intensity conditioning allogeneic stem cell transplantation for relapsed/refractory mantle cell lymphoma: a multicenter experience

BACKGROUND

Despite therapeutic approach that combines rituximab-containing chemotherapy, followed or not by autologous stem cell transplantation (auto-SCT), mantle cell lymphoma (MCL) patients experience relapses. Reduced-intensity conditioning allogeneic stem cell transplantation (RIC-allo-SCT) at time of relapse may represent an attractive strategy.

PATIENTS AND METHODS

We report a multicenter retrospective analysis. Seventy MCL patients underwent RIC-allo-SCT in 12 centers.

RESULTS

Median age at transplantation was 56 years and median time from diagnosis to transplantation was 44 months. The median number of previous therapies was 2 (range, 1-5) including autologous transplantation in 47 cases. At time of transplantation, 35 patients were in complete remission, 20 were in partial response and 15 in stable disease or progressive disease. The median follow-up for living patients was 24 months. The 2-year event-free survival (EFS) and overall survival (OS) rates were 50% and 53%, respectively. The 1- and 2-year transplant-related mortality rates were 22% and 32%, respectively. The statistical analysis demonstrated that disease status at transplantation was the only parameter influencing EFS and OS.

CONCLUSIONS

These results suggest that RIC-allo-SCT may be an effective therapy in MCL patients with a chemo-sensitive disease at time of transplantation, irrespective of the number of lines of prior therapy. Studies are warranted to investigate the best type of RIC regimen.

Relapsed and/or Refractory Mantle Cell Lymphoma: What Role for Temsirolimus?

Mantle Cell Lymphoma (MCL) is associated with a dismal prognosis. Recently, along with the improved understanding of the pathophysiology of this disease, new first line regimens have been established and in addition novel treatment options have entered the clinical arena. In consequence, prognosis of the disease has fortunately improved. We here focus on the rationale, current clinical knowledge and future concepts of Temsirolimus, an inhibitor of mTOR, in the treatment of MCL. At this time this drug has been shown to be effective as single agent for relapsed disease and early combination data show promising results. In addition, with a brief outline of other treatment options, we aim to guide at which place in the current treatment algorithms Temsirolimus can be integrated into the treatment of MCL patients.