Allogeneic hematopoietic cell transplantation after fludarabine and 2 Gy total body irradiation for relapsed and refractory mantle cell lymphoma

Aminoglycoside-free interventional antibiotic management in patients undergoing haemopoietic stem cell transplantation

The position of aminoglycosides within interventional antibiosis in the early phase after stem cell transplantation has not been fully clarified so far although their use can induce serious renal impairment. To investigate this question early-infection data from 152 patients undergoing 195 allogeneic and autologous stem cell transplantations were investigated. Prophylaxis and treatment of infections followed international standards; however, aminoglycosides were omitted to avoid additional risks such as ototoxicity and nephrotoxicity and increased selection of resistant pathogens. Costs were another aspect.

The overall-incidence of infections was 78% (152/195) and 67 patients showed more than one episode of infection. Fever of unknown origin and bacteriaemia/septicaemia dominated the spectrum of infections. The overall-response to interventional regimen consisting of β-lactam or carbapenem plus glycopeptides was 48%. Aminoglycosides were given in three patients in the late course of disease. Overall mortality was 15/195 (7.7%) and clearly related to infection in nine cases mostly due to mould infection. A comparison with previous published literature showed no hint for inferiority of ‘aminoglycoside-free’ antibiotic management in stem cell transplant patients. In conclusion, the present analysis supports the policy to omit aminoglycosides in the therapy of early infections in patients undergoing stem cell transplantation to avoid additional toxicity.

Radioimmunotherapy with yttrium-90-ibritumomab tiuxetan as part of a reduced- intensity conditioning regimen for allogeneic hematopoietic cell transplantation in patients with advanced non-Hodgkin lymphoma: results of a phase 2 study

Forty patients were enrolled in this phase 2 study combining radioimmunotherapy (RIT) using yttrium-90-ibritumomab-tiuxetan (15 MBq [0.4 mCi]/kg) with reduced-intensity conditioning (RIC) using fludarabine (90 mg/m2) and 2 Gy total body irradiation followed by allogeneic hematopoietic cell transplantation (HCT) from related (n = 13) or unrelated (n = 27) donors for the treatment of advanced non-Hodgkin lymphoma. Diagnoses were follicular lymphoma (n = 17), chronic lymphocytic leukemia (n = 13), mantle cell lymphoma (n = 8), marginal zone lymphoma (n = 1), and lymphoplasmacytic lymphoma (n = 1). Median age was 55 years (range, 34-68 years). All patients were high risk with refractory disease or relapse after preceding autologous HCT. No additional toxicities attributable to RIT were observed. Engraftment was rapid and sustained. Incidences of acute graft-versus-host disease 2-4 and chronic graft-versus-host disease were 43% and 53%, respectively. Kaplan-Meier–estimated nonrelapse mortality was 45% at 2 years. Twenty-two of 40 patients (55%) are alive, resulting in a Kaplan-Meier–estimated 2-year survival of 51% for all, 67% for follicular lymphoma, 49% for chronic lymphocytic leukemia, and 37% for mantle cell lymphoma patients. The combined use of RIT with RIC is feasible with acceptable toxicity, even in elderly and heavily pretreated patients. This study is registered at www.clinicaltrials.gov as #NCT00302757.

The B-cell tumor-associated antigen ROR1 can be targeted with T cells modified to express a ROR1-specific chimeric antigen receptor

Monoclonal antibodies and T cells modified to express chimeric antigen receptors specific for B-cell lineage surface molecules such as CD20 exert antitumor activity in B-cell malignancies, but deplete normal B cells. The receptor tyrosine kinase-like orphan receptor 1 (ROR1) was identified as a highly expressed gene in B-cell chronic lymphocytic leukemia (B-CLL), but not normal B cells, suggesting it may serve as a tumor-specific target for therapy. We analyzed ROR1-expression in normal nonhematopoietic and hematopoietic cells including B-cell precursors, and in hematopoietic malignancies. ROR1 has characteristics of an oncofetal gene and is expressed in undifferentiated embryonic stem cells, B-CLL and mantle cell lymphoma, but not in major adult tissues apart from low levels in adipose tissue and at an early stage of B-cell development. We constructed a ROR1-specific chimeric antigen receptor that when expressed in T cells from healthy donors or CLL patients conferred specific recognition of primary B-CLL and mantle cell lymphoma, including rare drug effluxing chemotherapy resistant tumor cells that have been implicated in maintaining the malignancy, but not mature normal B cells. T-cell therapies targeting ROR1 may be effective in B-CLL and other ROR1-positive tumors. However, the expression of ROR1 on some normal tissues suggests the potential for toxi-city to subsets of normal cells.

Tackling mantle cell lymphoma (MCL): Potential benefit of allogeneic stem cell transplantation

Mantle cell lymphoma (MCL) is a type of non-Hodgkins lymphoma (NHL) associated with poor progression-free and overall survival. There is a high relapse rate with conventional cytotoxic chemotherapy. Intensive combination chemotherapy including rituximab, dose intense CHOP- (cyclophosphamide-doxorubicin-vincristine-prednisone) like regimens, high dose cytarabine, and/or consolidation with autologous stem cell transplant (autoSCT) have shown promise in significantly prolonging remissions. Data from phase II studies show that even in patients with chemotherapy refractory MCL, allogeneic stem cell transplant (alloSCT) can lead to long term disease control. Most patients with MCL are not candidates for myeloablative alloSCT due to their age, comorbidities, and performance status. The advent of less toxic reduced intensity conditioning (RIC) regimens, which rely more on the graft-versus-lymphoma (GVL) effect, have expanded the population of patients who would be eligible for alloSCT. RIC regimens alter the balance of toxicity and efficacy favoring its use. Treatment decisions are complicated by introduction of novel agents which are attractive options for older, frail patients. Further studies are needed to determine the role and timing of alloSCT in MCL. Currently, for selected fit patients with chemotherapy resistant MCL or those who progress after autoSCT, alloSCT may provide long term survival.

Degrasyn potentiates the antitumor effects of bortezomib in mantle cell lymphoma cells in vitro and in vivo: therapeutic implications

Mantle cell lymphoma (MCL) is an aggressive histotype of B-cell non-Hodgkin lymphoma that has increased in incidence over the past few decades and is incurable, usually poorly responsive to standard chemotherapy combinations, and associated with poor prognoses. Discovering new therapeutic agents with low toxicity that produce better outcomes in patients with MCL is an ongoing challenge. Recent studies showed that degrasyn, a novel small-molecule inhibitor of the Janus kinase/signal transducer and activation of transcription (JAK/STAT) pathway, exerts antitumor activity in lymphoid tumors by inhibiting key growth and survival signaling (JAK/STAT) pathways. In the present study, we found that treatment of both typical and blastoid-variant MCL cells with degrasyn in combination with bortezomib resulted in synergistic growth inhibition and apoptosis induction in vitro. The apoptosis in these cells was correlated with the downregulation of constitutive NF-kappaB and phosphorylated STAT3 activation, leading to the inhibition of c-Myc, cyclin D1, and bcl-2 protein expression and the upregulation of bax protein expression. In vivo, degrasyn and bortezomib interacted to synergistically prevent tumor development and prolong survival durations in a xenotransplant severe combined immunodeficient mouse model of MCL. These findings suggest that agents such as degrasyn that can pharmacologically target constitutively expressed NF-kappaB and STAT3 in MCL cells may be useful therapeutic agents for MCL when administered together with bortezomib.

Hematopoietic stem cell transplantation for MDS

Hematopoietic stem cell transplantation (HSCT) offers potentially curative therapy for patients with myelodysplastic syndromes (MDS). However, as the majority of patients with MDS are in the seventh or eighth decade of life, conventional transplant regimens have been used only infrequently, and only with the development of reduced-intensity conditioning has transplantation been applied more broadly to older patients. Dependent upon disease status at the time of transplantation, 30% to 70% of patients can be expected to be cured of their disease and survive long term. However, posttransplant relapse and graft-versus-host disease (GVHD) remain problems and further investigations are needed.

Allogeneic hematopoietic cell transplantation: the state of the art

Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative procedure for a variety of hematologic malignancies. The field has evolved substantially over the past decade, with advances in patient and donor selection, stem cell sources, supportive care, prevention of complications and reduced-toxicity preparative regimens. As a result, the indications for HCT and the pool of eligible patients have expanded significantly. In this article, we provide an overview of the major aspects of allogeneic HCT, and focus specifically on areas of active research and on novel approaches to challenges in the field. Specifically, we will discuss approaches to reduce the toxicity of the preparative regimen, with the goal of increasing the safety and applicability of HCT. The availability of suitable donors may be an obstacle to wider application of HCT. We review three major approaches to broadening the donor pool: the use of HLA-mismatched unrelated donors, umbilical cord blood and HLA-haploidentical family donors. Graft-versus-host disease remains a major cause of morbidity and mortality after HCT. We review recent advances in the understanding of this phenomenon, and novel prophylactic and therapeutic approaches that hold the promise of further improving the safety of the procedure. We conclude with a speculative outline of the next 5 years of research in the field of HCT.

[Mantle cell lymphoma: an overview from diagnosis to future therapies]

Mantle cell lymphoma (MCL) is a rare non-Hodgkin lymphoma (NHL) entity. The translocation between chromosomes 11 and 14 is the cytogenetics hallmark of MCL. This translocation leads to the dysregulation of the CCDN1 gene, and overexpression of cyclin D1 which promotes cell cycling. Despite a classical phenotype (CD19+, CD20+, CD5+, CCND1+, CD10-, CD23-, Bcl-2+, Ig at the membrane, mainly IgM), MCL is not a homogeneous disease and several cytological, phenotypic, cytogenetic and clinical variants have been described. MCL represents 5 % of NHLs with its incidence constantly increasing over the last years. Median age at diagnosis is 68 years. Stage III-IV disease is observed in more than 80 % of patients at presentation, with intestinal and bone marrow being the most frequently involved organs, while the spleen is enlarged in half of cases. Intensive strategies including high-dose chemotherapy, followed by autologous stem cell transplantation have significantly improved the outcome of MCL patients. Median overall survival rate increased from 3 to 5 years during the last decade. At present, induction chemotherapy followed by high-dose chemotherapy and autologous stem cell transplantation is the standard regimen in younger patients. However, most of MCL patients will experience relapse. Thus, close monitoring of minimal residual disease (currently under evaluation) may represent a valuable tool for assessment of disease response during follow-up. Future innovative therapies that are being presently investigated in prospective trials include transduction pathways inhibitors, proteasome inhibitors, pro-apoptotic molecules, immunotherapy and/or radiolabeled immunotherapy, and will likely open a new era for targeted therapies in MCL.

NCI First International Workshop on the Biology, Prevention, and Treatment of Relapse after Allogeneic Hematopoietic Stem Cell Transplantation: report from the Committee on the Epidemiology and Natural History of Relapse following Allogeneic Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is increasingly being used for treatment of hematologic malignancies, and the immunologic graft-versus-tumor effect (GVT) provides its therapeutic effectiveness. Disease relapse remains a cause of treatment failure in a significant proportion of patients undergoing alloHSCT without improvements over the last 2-3 decades. We summarize here current data and outline future research regarding the epidemiology, risk factors, and outcomes of relapse after alloHSCT. Although some factors (eg, disease status at alloHSCT or graft-versus-host disease [GVHD] effects) are common, other disease-specific factors may be unique. The impact of reduced-intensity regimens on relapse and survival still need to be assessed using contemporary supportive care and comparable patient populations. The outcome of patients relapsing after an alloHSCT generally remains poor even though interventions including donor leukocyte infusions can benefit some patients. Trials examining targeted therapies along with improved safety of alloHSCT may result in improved outcomes, yet selection bias necessitates prospective assessment to gauge the real contribution of any new therapies. Ongoing chronic GVHD (cGVHD) or other residual post-alloHSCT morbidities may limit the applicability of new therapies. Developing strategies to promptly identify patients as alloHSCT candidates, while malignancy is in a more treatable stage, could decrease relapses rates after alloHSCT. Better understanding and monitoring of minimal residual disease posttransplant could lead to novel preemptive treatments of relapse. Analyses of larger cohorts through multicenter collaborations or registries remain essential to probe questions not amenable to single center or prospective studies. Studies need to provide data with detail on disease status, prior treatments, biologic markers, and posttransplant events. Stringent statistical methods to study relapse remain an important area of research. The opportunities for improvement in prevention and management of post-alloHSCT relapse are apparent, but clinical discipline in their careful study remains important.

Evaluation of the (R)VAD+C regimen for the treatment of newly diagnosed mantle cell lymphoma. Combined results of two prospective phase II trials from the French GOELAMS group

Background There is currently no international consensus for first-line treatment (prior to autologous stem cell transplantation) in mantle cell lymphoma patients. Here, we investigated the efficacy and tolerance of VAD associated with chlorambucil (VAD+C) and rituximab or not before autologous stem cell transplantation.

DESIGN AND METHODS

Between 1996 and 2005, 113 previously untreated mantle cell lymphoma patients were enrolled in two consecutive prospective phase II studies. Responses and response factors to the (R)VAD+C regimen were evaluated. The survival prognostic value of the MIPI score and Ki67 were also analyzed.

RESULTS

The induction phase of 4 courses of (R)VAD+C showed very low hematologic and extra-hematologic toxicity (grade 3-4 thrombopenia and neutropenia, 9% and 2.7%, respectively and grade 3-4 extra-hematologic toxicities, 1.6%). Overall and complete response rates were 73% and 46%, respectively, and rose to 83% and 51% for the 70% of patients with less than two independent response factors (LDH, B symptoms and lymphocytosis). At the end of treatment, 65% of patients were in complete remission. Progression free and overall survival were significantly better in the transplanted population. The MIPI score was confirmed as a predictor of survival. Ki67, serum LDH, Performance Status (PS) and B symptoms were identified as independent prognostic factors of survival. A prognostic scoring system could stratify patients into three risk groups with markedly different median overall survival of 112, 44 and 11 months, respectively. Conclusions The (R)VAD+C is an effective regimen with very low toxicity. In addition to the MIPI score, Ki67 expression provides additional independent prognostic information for the prediction of overall survival (ClinicalTrials.gov Identifier: NCT00285389).

Mantle cell lymphoma - does primary intensive immunochemotherapy improve overall survival for younger patients?

MCL is a rare entity of non-Hodgkin lymphoma, hitherto considered incurable. There is no standard therapy, but the current treatment results do seem to have led to a prolongation of the median survival from 3 to 5 years. Following CHOP-like induction, high-dose radiochemotherapy, and autologous stem cell transplantation (ASCT) chemotherapy has been shown in a controlled trial to be superior in younger patients, but does not, however, lead to long-term freedom from disease. Results of recent prospective but uncontrolled trials of more intensive frontline immunochemotherapy containing cytarabine and rituximab followed by ASCT, however, now for the first time indicate plateaus of the curves of event-free, progression-free and overall survival, suggesting cure, but more studies and longer follow-up is needed. Following relapse, autologous stem-cell transplantation does not seem to be of value, but graft-versus-lymphoma effect has been documented, and allogeneic stem cell transplantation with reduced-intensity conditioning is emerging as the treatment of choice in this setting.

Autologous and allogeneic stem cell transplantation: rising therapeutic promise for mantle cell lymphoma

Mantle cell lymphoma (MCL) is currently an incurable neoplasm with a median survival duration of 3-5 years. The clinical results of therapy with cyclophosphamide, doxorubicin, vincristine, and prednisone or similar regimens are inadequate,leading to widespread exploration of the use of autologous stem cell transplantation (ASCT) during the first remission. In the pre-rituximab era, early ASCT extended the median remission duration by 1-2 years, but most patients eventually experienced relapse. With the advent of rituximab and its incorporation into stem cell mobilization and conditioning regimens, several research groups have reported improved outcomes, including the emergence of early survival curve plateaus that suggest a cured fraction. Intensive chemoimmunotherapy with rituximab and hyperfractionated cyclophosphamide,vincristine, doxorubicin, and dexamethasone has been reported to have similarly favorable results. Therefore, the addition of rituximab to intensive chemotherapy or ASCT regimens may be curative in patients undergoing frontline treatment for MCL. In the relapsed or refractory disease setting, the clinical results of ASCT remain inadequate. However, the increasing safety and high efficacy of non-myeloablative stem cell transplantation (SCT) suggests that it is the most appropriate transplantation modality in patients with relapsed or refractory MCL when a suitable donor is available.

Mantle cell lymphoma: are current therapies changing the course of disease?

Mantle cell lymphoma (MCL) is a rare entity of non-Hodgkin's lymphoma, although it seems to be increasing in incidence and severity. There is no accepted standard therapy; however, one controlled clinical trial demonstrated that intensive induction immunochemotherapy followed by high-dose radiochemotherapy and autologous stem cell transplantation was superior to conventional treatment. Moreover, uncontrolled studies of intensive immunochemotherapy followed by autologous stem cell transplantation now suggest that MCL may be cured. Insight into the biology of MCL is expanding, opening new avenues of treatment with well-defined molecular targets, including CD20, mammalian target of rapamycin, and proteasomes.

Second-line age-adjusted International Prognostic Index in patients with advanced non-Hodgkin lymphoma after T-cell depleted allogeneic hematopoietic SCT

T-cell depleted allogeneic hematopoietic SCT (TCD-HSCT) have shown durable disease-free survival with a low risk of GVHD in patients with AML. We investigated this approach in 61 patients with primary refractory or relapsed non-Hodgkin lymphoma (NHL), who underwent TCD-HSCT from January 1992 through September 2004. Patients received myeloablative cytoreduction consisting of hyperfractionated total body irradiation, followed by either thiotepa and cyclophosphamide (45 patients) or thiotepa and fludarabine (16 patients). We determined the second-line age-adjusted International Prognostic Index score (sAAIPI) before transplant transplant. Median follow-up of surviving patients is 6 years. The 10-year OS and EFS were 50% and 43%, respectively. The relapse rate at 10 years was 21% in patients with chemosensitive disease and 52% in those with resistant disease at time of HSCT. Nine of the 18 patients who relapsed entered a subsequent CR. OS (P=0.01) correlated with the sAAIPI. The incidence of grades II-IV acute GVHD was 18%. We conclude that allogeneic TCD-HSCT can induce high rates of OS and EFS in advanced NHL with a low incidence of GVHD. Furthermore, the sAAIPI can predict outcomes and may be used to select the most appropriate patients for this type of transplant.

Low-dose total body irradiation and fludarabine conditioning for HLA class I-mismatched donor stem cell transplantation and immunologic recovery in patients with hematologic malignancies: a multicenter trial

HLA-mismatched grafts are a viable alternative source for patients without HLA-matched donors receiving ablative hematopoietic cell transplantation (HCT), although their use in reduced intensity conditioning (RIC) or nonmyeloablative (NMA) conditioning HCT has been not well established. Here, we extended HCT to recipients of HLA class I-mismatched grafts to investigate whether NMA conditioning can establish stable donor engraftment. Fifty-nine patients were conditioned with fludarabine (Flu) 90 mg/m(2) and 2 Gy total body irradiation (TBI), followed by immunosuppression with cyclosporine (CsA) 5.0 mg/kg twice a day and mycophenolate mofetil (MMF) 15 mg/kg 3 times a day for transplantation of granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cells (PBSCs) from related (n = 5) or unrelated donors (n = 54) with 1 antigen +/- 1 allele HLA class I mismatch or 2 HLA class I allele mismatches. Sustained donor engraftment was observed in 95% of the evaluable patients. The incidence of grade II-IV acute and extensive chronic graft-versus-host disease (aGVHD, cGVHD) was 69% and 41%, respectively. The cumulative probability of nonrelapse mortality (NRM) was 47% at 2 years. Two-year overall and progression-free survival (OS, PFS) was 29% and 28%, respectively. NMA conditioning with Flu and low-dose TBI, followed by HCT using HLA class I-mismatched donors leads to successful engraftment and long-term survival; however, the high incidence of aGVHD and NRM needs to be addressed by alternate GVHD prophylaxis regimens.

Construction and preclinical evaluation of an anti-CD19 chimeric antigen receptor

T cells can be engineered to express the genes of chimeric antigen receptors (CARs) that recognize tumor-associated antigens. We constructed and compared 2 CARs that contained a single chain variable region moiety that recognized CD19. One CAR contained the signaling moiety of the 4-1BB molecule and the other did not. We selected the CAR that did not contain the 4-1BB moiety for further preclinical development. We demonstrated that gammaretroviruses encoding this receptor could transduce human T cells. Anti-CD19-CAR-transduced CD8+ and CD4+ T cells produced interferon-gamma and interleukin-2 specifically in response to CD19+ target cells. The transduced T cells specifically killed primary chronic lymphocytic leukemia (CLL) cells. We transduced T cells from CLL patients that had been previously treated with chemotherapy. We induced these T cells to proliferate sufficiently to provide enough cells for clinical adoptive T cell transfer with a protocol consisting of an initial stimulation with an anti-CD3 monoclonal antibody (OKT3) before transduction followed by a second OKT3 stimulation 7 days after transduction. This protocol was successfully adapted for use in CLL patients with high peripheral blood leukemia cell counts by depleting CD19+ cells before the initial OKT3 stimulation. In preparation for a clinical trial that will enroll patients with advanced B cell malignancies, we generated a producer cell clone that produces retroviruses encoding the anti-CD19 CAR, and we produced sufficient retroviral supernatant for the proposed clinical trial under good manufacturing practice conditions.

Total lymphoid irradiation for graft-versus-host disease protection

PURPOSE

The immunosuppressive effects of total lymphoid irradiation (TLI) for protection against graft-versus-host disease (GvHD) after allogeneic bone marrow transplantation have been studied for years in animal models. In preclinical models of bone marrow transplantation non-myeloablative TLI conditioning protects against GvHD by skewing host T-cell subsets to favor regulatory natural killer T cells that suppress GvHD by polarizing donor T cells towards secretion of non-inflammatory cytokines such as IL-4. These preclinical models have recently been adapted to human transplantation.

RECENT FINDINGS

Patients receiving allogeneic hematopoietic cell transplantation for hematological malignancies conditioned with TLI and depletive T-cell antibodies showed sustained donor chimerism, a reduced incidence of acute GvHD yet retained anti-tumor activity. As in the preclinical models, the low incidence of GvHD is associated with increased IL-4 secretion by chimeric donor T cells.

SUMMARY

This review summarizes the evolution of the preclinical TLI protocols and their recent translation to clinical trials, and discusses the mechanisms involved in protection from GvHD and the induction of tolerance following mixed chimerism.

The allogeneic graft-versus-cancer effect

Allogeneic haematological stem cell transplantation (HSCT) has developed into immunotherapy. Donor CD4+, CD8+ and natural killer (NK) cells have been reported to mediate graft-versus-leukaemia (GVL) effects, using Fas-dependent killing and perforin degranulation to eradicate malignant cells. Cytokines, such as interleukin-2, interferon-gamma and tumour necrosis factor-alpha potentiate the GVL effect. Post-transplant adoptive therapy of cytotoxic T-cells (CTL) against leukaemia-specific antigens, minor histocompatibility antigens, or T-cell receptor genes may constitute successful approaches to induce anti-tumour effects. Clinically, a significant GVL effect is induced by chronic rather than acute graft-versus-host disease (GVHD). An anti-tumour effect has also been reported for myeloma, lymphoma and solid tumours. Reduced intensity conditioning enables HSCT in older and disabled patients and relies on the graft-versus-tumour effect. Donor lymphocyte infusions promote the GVL effect and can be given as escalating doses with response monitored by minimal residual disease. A high CD34+ cell dose of peripheral blood stem cells increases GVL. There is a balance between effective immunosuppression, low incidence of GVHD and relapse. For instance, T-cell depletion of the graft increases the risk of relapse. This paper reviews the current knowledge in graft-versus-cancer effects. Future directions, such as immunotherapy using leukaemia-specific CTLs, allo-depleted T-cells and suicide gene manipulated T-cells, are presented.

How I treat mantle cell lymphoma

Mantle cell lymphoma is included in the World Health Organization classification as distinct lymphoma subtype characterized by the t(11;14)(q13;q32) translocation, which results in overexpression of Cyclin D1. The clinical presentation often includes extranodal involvement, particularly of the bone marrow and gut. The prognosis of patients with mantle cell lymphoma (median overall survival, 3-5 years) is poorest among B-cell lymphoma patients, even though a prospectively difficult to identify subgroup can survive for years with little or no treatment. Conventional chemotherapy is not curative but obtains frequent remissions (60%-90%) which are usually shorter (1-2 years) compared with other lymphoma entities. Very intensive regimens, including autologous and allogeneic stem cell transplantation, seem required to improve the outcome, but with the median age of diagnosis being 60 years or more, such approaches are feasible only in a limited proportion of patients. The possibility of treating patients based on prognostic factors needs to be investigated prospectively.

Allogeneic stem-cell transplantation with fludarabine and 2-Gy TBI-based conditioning regimen for chronic hematological malignancy: A study of 25 consecutive patients and a literature review

We analyzed the outcome of 25 consecutive patients with chronic hematological malignancy who underwent allogeneic stem-cell transplantation conditioned with fludarabine (30 mg/m2/day, thrice) and total body irradiation (2 Gy). All patients received peripheral blood stem cells from an HLA-identical sibling donor. With a median follow-up of 769 days (range, 244 - 1231), the estimated 2-year overall survival (OS), event-free survival (EFS), transplantation-related mortality and relapse rates were 53%, 45%, 27%, and 39%, respectively. All patients had initial engraftment. Acute Grade II - IV graft-versus-host disease (GVHD) was recorded in 14 patients (56%), including 7 (28%) with Grade III - IV GVHD. Sixteen of the 23 patients (70%) who survived more than 100 days developed chronic GVHD. OS and EFS were adversely influenced by acute Grade III - IV GVHD (p < 0.001 and p = 0.033, respectively), but chronic GVHD seemed to favorably influence these two parameters (p = 0.03 and p < 0.001, respectively). Patients with full-donor chimerism at day 30 had lower relapse rates, as did those who received high-dose allogeneic CD8+ lymphocytes with their graft (p = 0.026). Collectively, these results provide a framework for refining nonmyeloablative conditioning, to improve outcome with an acceptable risk of GVHD.

Controversies in lymphoma: the role of hematopoietic cell transplantation for mantle cell lymphoma and peripheral T cell lymphoma

Mantle cell lymphoma (MCL) and peripheral T cell lymphoma (PTCL) are distinct lymphoma subtypes that each comprise about approximately 10% of the non-Hodgkin lymphomas. Although both subtypes are characterized by high remission rates to frontline chemotherapy, the prognosis is generally poor because of inevitable relapse within 1-2 years or less, depending on the specific histology. Patients with MCL who achieve a complete remission with upfront conventional chemotherapy currently have several options for consolidative therapy including maintenance therapy with rituximab, autologous hematopoietic cell transplantation (HCT), and more recently, allogeneic HCT utilizing a reduced intensity conditioning (RIC) regimen. In the autologous HCT setting, the added efficacy of rituximab is under active investigation as a method of in vivo purging during hematopoietic cell mobilization, as part of the conditioning regimen and as post-HCT maintenance therapy. For patients with PTCL, autologous HCT is commonly offered at relapse but there are a few prospective series utilizing autologous HCT as consolidation of CR1 with encouraging results. There is no conclusive evidence regarding the efficacy of allogeneic HCT, but outcomes with RIC regimens appear promising. This review summarizes the current role of HCT for patients with MCL in first remission and for patients with PTCL as consolidation and for relapsed/refractory disease.

TLI and ATG conditioning with low risk of graft-versus-host disease retains antitumor reactions after allogeneic hematopoietic cell transplantation from related and unrelated donors

A hematopoietic cell transplantation regimen was adapted from a preclinical model that used reduced-intensity conditioning (RIC) and protected against graft-versus-host disease (GVHD) by skewing residual host T-cell subsets to favor regulatory natural killer T cells. One hundred eleven patients with lymphoid (64) and myeloid (47) malignancies received RIC using total lymphoid irradiation (TLI) and antithymocyte globulin (ATG) followed by the infusion of granulocyte colony-stimulating factor-mobilized grafts. Included were 34 patients at least 60 years of age, 32 patients at high risk of lymphoma relapse after disease recurrence following prior autologous transplantation, and 51 patients at high risk of developing GVHD due to lack of a fully human leukocyte antigen (HLA)-matched related donor. Durable chimerism was achieved in 97% of patients. Cumulative probabilities of acute GVHD (grades II-IV) were 2 and 10% of patients receiving related and unrelated donor grafts. Nonrelapse mortality (NRM) at 1 year was less than 4%. Cumulative incidence of chronic GVHD was 27%. The 36-month probability of overall and event-free survival was 60% and 40%, respectively. Disease status at start of conditioning and the level of chimerism achieved after transplantation significantly impacted clinical outcome. The high incidence of sustained remission among patients with active disease at time of transplantation suggests retained graft-versus-tumor reactions. Active trial registration currently at clinicaltrials.gov under IDs of NCT00185640 and NCT00186615.

Effect of conditioning regimen intensity on CMV infection in allogeneic hematopoietic cell transplantation

Nonmyeloablative conditioning is less toxic and results in initial establishment of mixed hematopoietic T cell chimerism for up to half a year with prolonged presence of host T cell immunity. In this study, we examined whether this translates into differences in the risks and/or severity of cytomegalovirus (CMV) infection and disease. We analyzed data from 537 nonmyeloablative (NM-HCT) and contemporaneous 2489 myeloablative hematopoietic cell transplant (M-HCT) recipients. In CMV seropositive recipients, no difference in the overall hazards of CMV infection at any level (adjusted hazard ratio [adj. HR] 0.9, 95% confidence interval [95% CI]: 0.7-1.0, P = .14) was noted; however, NM-HCT was associated with a lower risk of high-grade CMV infection (adj. HR 0.7, 95% CI: 0.5-0.9, P = .02). CMV disease rates were similar between the groups during the first 100 days after HCT, but NM-HCT recipients had an increased risk of late CMV disease (adj. HR 2.0, 95% CI 1.2-3.4). The increased risk of late CMV disease after NM-HCT was pronounced during the earlier years of the study period, but not detectable in more recent years. Contrary to earlier reports, survival following CMV disease was not reduced after NM-HCT when compared to M-HCT recipients. These results suggest that residual host cells after NM-HCT reduce progression to higher CMV viral load in NM-HCT recipients; however, this effect does not appear to protect against serious complications of CMV. Therefore, CMV prevention strategies in NM-HCT recipients should be similar to those used in M-HCT recipients.

Comorbidities and survival in a large cohort of patients with newly diagnosed myelodysplastic syndromes

Comorbid conditions have rarely been systematically studied among patients with myelodysplastic syndromes (MDS). We conducted a large population-based study to assess the role of comorbidity in the survival of newly diagnosed MDS patients. This study included 1708 MDS patients (age > or =66 years) diagnosed in the US during 2001-2002, with follow-up through the end of 2004. Hazard ratios (HRs) were estimated using multivariate Cox proportional hazard models. The median survival time was approximately 18 months. Fifty one percent of MDS patients had comorbid conditions. Patients with comorbid conditions had significantly greater risk of death than those without comorbidities. The HR was 1.19 (95% confidence interval (CI): 1.05-1.36) and 1.77 (95% CI: 1.50-2.08) for those with a Charlson index of 1-2 and > or = 3, respectively. The risk of death increases with Charlson index. MDS patients who have congestive heart failure or chronic obstructive pulmonary disease had significantly shorter survival than patients without those conditions, whereas diabetes did not appear to have an impact on survival. This study confirms comorbidity as a significant and independent determinant of MDS survival, and the findings underscore the importance to take comorbid conditions into account when assessing the prognosis of MDS.

Graft-versus-leukemia effects of transplantation and donor lymphocytes

Allogeneic transplantation of hematopoietic cells is an effective treatment of leukemia, even in advanced stages. Allogeneic lymphocytes produce a strong graft-versus-leukemia (GVL) effect, but the beneficial effect is limited by graft-versus-host disease (GVHD). Depletion of T cells abrogates GVHD and GVL effects. Delayed transfusion of donor lymphocytes into chimeras after T cell-depleted stem cell transplantation produces a GVL effect without necessarily producing GVHD. Chimerism and tolerance provide a platform for immunotherapy using donor lymphocytes. The allogeneic GVL effects vary from one disease to another, the stage of the disease, donor histocompatibility, the degree of chimerism, and additional treatment. Immunosuppressive therapy before donor lymphocyte transfusions may augment the effect as well as concomitant cytokine treatment. Possible target antigens are histocompatibility antigens and tumor-associated antigens. Immune escape of tumor cells and changes in the reactivity of T cells are to be considered. Durable responses may be the result of the elimination of leukemia stem cells or the establishment of a durable immune control on their progeny. Recently, we have learned from adoptive immunotherapy of viral diseases and HLA-haploidentical stem cell transplantation that T-cell memory may be essential for the effective treatment of leukemia and other malignancies.

Therapy of mantle cell lymphoma: current standards and future strategies

Mantle cell lymphoma is characterized clinically by an aggressive clinical course and is relatively resistant to conventional chemotherapies. When in its advanced stages, currently available immunochemotherapy regimens remain noncurative despite high initial response rates. In contrast, consolidating high-dose therapy with autologous stem cell retransfusion significantly extends progression-free survival of young patients. Currently, allogenic bone marrow transplantation represents the only therapy with the potential for a curative approach, although associated with a high rate of complications. New concepts of therapy are urgently warranted, including new molecular approaches, such as bortezomib, thalidomide, lenalidomide, and temsirolimus.

Stem cell transplantation for non-Hodgkin's lymphoma

Non-Hodgkin's lymphoma (NHL) includes a diverse set of conditions ranging from high-grade aggressive to more indolent low-grade disease. Hematopoietic stem cell transplantation (HSCT) has a valuable role in the management of these conditions and can provide long-term remission in selected cases. This article presents the current use of allogeneic and autologous HSCT in a number of subtypes of NHL.

Analysis of risk factors for outcomes after unrelated cord blood transplantation in adults with lymphoid malignancies: a study by the Eurocord-Netcord and lymphoma working party of the European group for blood and marrow transplantation

PURPOSE

To determine risk factors of umbilical cord blood transplantation (UCBT) for patients with lymphoid malignancies.

PATIENTS AND METHODS

We evaluated 104 adult patients (median age, 41 years) who underwent unrelated donor UCBT for lymphoid malignancies. UCB grafts were two-antigen human leukocyte antigen-mismatched in 68%, and were composed of one (n = 78) or two (n = 26) units. Diagnoses were non-Hodgkin's lymphoma (NHL, n = 61), Hodgkin's lymphoma (HL, n = 29), and chronic lymphocytic leukemia (CLL, n = 14), with 87% having advanced disease and 60% having experienced failure with a prior autologous transplant. Sixty-four percent of patients received a reduced-intensity conditioning regimen and 46% low-dose total-body irradiation (TBI). Median follow-up was 18 months.

RESULTS

Cumulative incidence of neutrophil engraftment was 84% by day 60, with greater engraftment in recipients of higher CD34(+) kg/cell dose (P = .0004). CI of non-relapse-related mortality (NRM) was 28% at 1 year, with a lower risk in patients treated with low-dose total-body irradiation (TBI; P = .03). Cumulative incidence of relapse or progression was 31% at 1 year, with a lower risk in recipients of double-unit UCBT (P = .03). The probability of progression-free survival (PFS) was 40% at 1 year, with improved survival in those with chemosensitive disease (49% v 34%; P = .03), who received conditioning regimens containing low-dose TBI (60% v 23%; P = .001), and higher nucleated cell dose (49% v 21%; P = .009).

CONCLUSION

UCBT is a viable treatment for adults with advanced lymphoid malignancies. Chemosensitive disease, use of low-dose TBI, and higher cell dose were factors associated with significantly better outcome.

Long-term results of the treatment of patients with mantle cell lymphoma with cladribine (2-CDA) alone (95-80-53) or 2-CDA and rituximab (N0189) in the North Central Cancer Treatment Group

BACKGROUND

The objective of this study was to test cladribine (2-CDA) alone and in combination with rituximab in patients with mantle cell lymphoma (MCL).

METHODS

Patients with MCL were treated on 2 sequential trials. In Trial 95-80-53, patients received 2-CDA as initial therapy or at relapse. In Trial N0189, patients received combination 2-CDA and rituximab as initial therapy. In both trials, 2-CDA was administered at a dose of 5 mg/m2 intravenously on Days 1 through 5 every 4 weeks for 2 to 6 cycles, depending on response. In Trial N0189, rituximab 375 mg/m2 was administered on Day 1 of each cycle.

RESULTS

Results were reported for 80 patients. Twenty-six previously untreated patients and 25 patients who had recurrent disease with a median age of 68 years received single-agent 2-CDA. The overall response rate (ORR) was 81% with 42% complete responses (CRs) in the previously untreated group. The median progression-free survival (PFS) was 13.6 months (95% confidence interval [95% CI], 7.2-22.1 months), and 81% of patients remained alive at 2 years. The ORR was 46% with a 21% CR rate in the recurrent disease group. The median PFS was 5.4 months (95% CI, 4.6-13.1 months), and 36% of patients remained alive at 2 years. Twenty-nine eligible patients with a median age of 70 years received 2-CDA plus rituximab. The ORR was 66% (19 of 29 patient), and the CR rate was 52% (15 of 29 patients). The median duration of response for patients who achieved a CR had not been reached at the time of the current report, and only 3 of the patients who achieved a CR developed recurrent disease at a median follow-up of 21.5 months.

CONCLUSIONS

2-CDA had substantial single-agent activity in both recurrent and untreated MCL, and the results indicated that it may be administered safely to elderly patients. The addition of rituximab to 2-CDA may increase the duration of response.

Mantle cell lymphoma: advances in biology and therapy

PURPOSE OF REVIEW

Mantle cell lymphoma is characterized by dysregulation of cyclin D1, but this is not sufficient for lymphoma development. It is a difficult disease to treat, being incurable with standard chemotherapy and having a median survival of approximately 5 years. The purpose of this review is to update recent advances in mantle cell lymphoma biology with prognostic and potentially therapeutic implications, and mantle cell lymphoma treatment approaches and new agents.

RECENT FINDINGS

Genetic alterations that cooperate with cyclin D1 have been described that alter proliferation, in particular p27Kip and p16INK4, or apoptosis. Biological factors such as high-proliferation signature defined by gene expression profiles, loss of p27 and presence of mutant p53 confer poor prognosis. Proliferative rate also predicts patient outcome. Clinical criteria such as the international prognostic index, follicular lymphoma international prognostic index or a formula using age, performance status, white blood cell count and lactate dehydrogenase, separate prognostic groups. Not all patients require therapy at diagnosis. Although the best reported results have been with rituximab-hyperfractionated cyclophosphamide-vincristine-doxorubicin-dexamethasone-methotrexate/cytarabine, a cooperative group study of this regimen appears not quite as successful. Consolidation of remission after rituximab-cyclophosphamide-doxorubicin-vincristine-prednisone with high-dose therapy/stem-cell support prolongs remission and consolidation with radioimmunotherapy shows promise. Intensifying induction by alternating intensified rituximab-cyclophosphamide-doxorubicin-vincristine-prednisone with rituximab and high-dose cytarabine, followed by high-dose therapy appears quite promising. Novel agents active in relapsed disease include bortezomib, mammalian target of rapamycin inhibitors, immunomodulatory agents, antibodies and cyclin pathway-directed agents such as flavopiridol and cyclin-dependent kinase inhibitors.

SUMMARY

New insights into mantle cell lymphoma biology may lead to targeted therapy. Meanwhile, combinations of existing therapeutic approaches seem to have improved outcomes.

Hematopoietic cell transplantation for patients with myelodysplastic syndromes (MDS): when, how and for whom?

Hematopoietic cell transplantation (HCT) offers potentially curative therapy for patients with myelodysplastic syndromes (MDS). However, who should and can be transplanted, with which approach, and when is a matter of debate. Various classification schemes and prognostic scoring systems have helped in the decision-making process. Offering HCT to patients who were not considered transplant candidates in the past is now possible with the development of new transplant strategies. In addition to disease stage, patient age, comorbid conditions, preHCT chemotherapy, type of donor, source of stem cells, and possibly other factors, need to be considered prior to transplant. Patients without substantial comorbid conditions up to 60 years with the availability of unrelated donor grafts or 65 years with related donor grafts can be transplanted with more conventional (higher dose) regimens (e.g. targeted BU/CY; Flu/BU). Older patients and patients with comorbid conditions should be enrolled in trials aimed at optimizing RIC/nonmyeloablative HCT (e.g. Flu/melphalan; Flu/low dose TBI). Patients who present with 'advanced' MDS or are transfusion dependent, and do not have a del(5q), should probably be transplanted early in their course. GVHD (in all patients) and post-HCT relapse (in patients with high risk disease) remain major problems. Modifications of transplant conditioning regimens have reduced transplant-related mortality and allow successful HCT even in older patients. However, prospective randomized trials are needed to determine the role of pre-HCT chemotherapy and the type of transplant conditioning regimen best suited for a given patient.

Adoptive immunotherapy for indolent non-Hodgkin lymphoma and mantle cell lymphoma using genetically modified autologous CD20-specific T cells

Adoptive immunotherapy with T cells expressing a tumor-specific chimeric T-cell receptor is a promising approach to cancer therapy that has not previously been explored for the treatment of lymphoma in human subjects. We report the results of a proof-of-concept clinical trial in which patients with relapsed or refractory indolent B-cell lymphoma or mantle cell lymphoma were treated with autologous T cells genetically modified by electroporation with a vector plasmid encoding a CD20-specific chimeric T-cell receptor and neomycin resistance gene. Transfected cells were immunophenotypically similar to CD8(+) effector cells and showed CD20-specific cytotoxicity in vitro. Seven patients received a total of 20 T-cell infusions, with minimal toxicities. Modified T cells persisted in vivo 1 to 3 weeks in the first 3 patients, who received T cells produced by limiting dilution methods, but persisted 5 to 9 weeks in the next 4 patients who received T cells produced in bulk cultures followed by 14 days of low-dose subcutaneous interleukin-2 (IL-2) injections. Of the 7 treated patients, 2 maintained a previous complete response, 1 achieved a partial response, and 4 had stable disease. These results show the safety, feasibility, and potential antitumor activity of adoptive T-cell therapy using this approach. This trial was registered at www.clinicaltrials.gov as #NCT00012207.

Advances in the understanding of mantle cell lymphoma

Mantle cell lymphoma (MCL) is a well-defined lymphoid neoplasm characterized by a proliferation of mature B lymphocytes expressing CD5 that may show a spectrum of morphological and phenotypic features broader than initially described. Although some patients may follow an indolent clinical evolution, in most of them the tumour has an aggressive behaviour with poor response to conventional chemotherapy. The genetic hallmark is the t(11;14)(q13;q32) translocation leading to the overexpression of cyclin D1, which is considered the initial oncogenic event. In addition to this translocation, MCL may carry a high number of secondary chromosomal and molecular alterations that target regulatory elements of the cell cycle machinery and senescence (BMI1/INK4/ARF/CDK4/RB1), DNA damage response pathways (ATM/CHK2/p53), and cell survival signals. The knowledge of these mechanisms and their influence on the behaviour of the tumour are facilitating the development of prognostic models with a more precise prediction of the clinical evolution of the patients. This information coupled with the availability of a new generation of innovative drugs targeting basic molecular process of the tumour cells, should facilitate the design of new therapeutic protocols able to overcome the resistance of this aggressive lymphoma to conventional treatments and improve the life expectancy of the patients.

Therapeutic options in mantle cell lymphoma

Mantle cell lymphoma (MCL) is an aggressive lymphoma requiring intensive chemotherapy +/- autologous stem cell transplantation (SCT) to achieve optimal rates of progression-free survival. Here we review the treatment options for patients with newly-diagnosed or relapsed MCL and discuss recent advances in management, including the role of autologous and allogeneic SCT.

Allogeneic transplantation with reduced-intensity conditioning for Hodgkin and non-Hodgkin lymphoma: importance of histology for outcome

Allogeneic stem cell transplantation (SCT) with reduced-intensity conditioning (RIC) has the potential to lead to long-term remissions for patients with lymphoma. However, the role of RIC SCT in the treatment of lymphoma is still unclear. Specifically, the relative benefit of RIC SCT across lymphoma histologies and the prognostic factors in this population are incompletely defined. We retrospectively analyzed the outcomes of 87 patients with advanced lymphoma who underwent RIC SCT at the Dana-Farber Cancer Institute over a 6-year period with a homogeneous conditioning regimen consisting of fludarabine and low-dose busulfan. Thirty-six patients had Hodgkin disease (HD) and 51 had non-Hodgkin lymphoma (NHL). Sixty-eight percent had undergone prior autologous transplantation. The 1-year cumulative incidence of nonrelapse mortality was 13%, and the 3-year cumulative incidence of progression was 49%. The incidence of grade 3-4 acute GVHD was 11%. The 2-year cumulative incidence of chronic GVHD was 68%, and its development was associated with a decreased risk of progression and an improved progression-free survival (PFS). Three-year overall survival (OS) was 56% for patients with HD, 81% for indolent NHL, 42% for aggressive NHL, and 40% for mantle cell lymphoma. The corresponding figures for 3-year PFS were 22%, 59%, 22%, and 30%, respectively. Multivariate analysis identified elevated pretransplantation lactate dehydrogenase (LDH) as an adverse factor for PFS, while indolent NHL histology was favorable. For OS, advanced age and elevated pretransplantation LDH were adverse factors, whereas indolent NHL histology was favorable. Low early donor chimerism was not predictive of poor outcome in univariate or multivariate analyses. Moreover, progression was not associated with loss of chimerism. These results emphasize the importance of lymphoma histology for patients undergoing RIC SCT, as well as the lack of relevance of donor chimerism for outcome in this patient population.

Bortezomib in mantle cell lymphoma

Mantle cell lymphoma (MCL) represents 6% of non-Hodgkin lymphomas, but is one of the most active fields of clinical investigation. Unfortunately, there is still no standard or curative therapy in MCL. Front-line therapy appears to benefit from intensification either through high-dose therapy with stem cell transplant consolidation or dose-intense chemotherapy with hyperfractionated cyclophosphamide, vincristine, adriamycin/doxorubicin and dexamethasone/rituximab. Most patients still relapse and a multitude of novel agents are currently being tested in this setting, including proteasome inhibitors with bortezomib (the first of its class and the first US FDA-approved drug for MCL), mTOR inhibitors, Bcl-2 inhibitors, antiangiogenesis agents and histone deacetylase inhibitors among others. An obvious effort is needed to enroll patients on clinical trials, the design of which might benefit from pharmacogenomics and a better understanding of MCL biology and its diversity.

Immunotherapy in mantle cell lymphoma: anti-CD20-based therapy and beyond

Mantle cell lymphoma (MCL), an aggressive non-Hodgkin's lymphoma characterized by t(11; 14)(q13; q32) chromosomal translocation and overexpression of cyclin D1, has the worst prognosis among all lymphomas. Recent advances in biology, genetics, and immunology have supported the development of immunotherapy in MCL. Rituximab monotherapy in MCL has limited activity. It is more effective when used in combination with chemotherapy such as R-CHOP, R-hyperCVAD/MTX-Ara-C, or R-FCM as front-line or salvage therapy for mantle cell lymphoma. Maintenance with Rituximab was shown to prolong response duration. Although most results have suggested that combining autologous stem cell transplantation with Rituximab may lead to durable remission, the sample size was not sufficient to declare survival benefit. Anti-CD20 radioimmunoconjugates (RICs) (90)Yttrium-ibritumomab tiuxetan and (131)Iodine-tositumomab have been used in mantle cell lymphoma even when patients are relatively resistant to Rituximab-based therapy. Allogeneic stem cell transplantation is a treatment modality in advanced or relapsed MCL, particularly using reduced-intensity conditioning. MCL may have high response rates and sustained remissions after donor lymphocyte infusion. Dendritic cells (DCs) fused with MCL cells for immunostimulation have preliminarily shown anti-lymphoma effects as well. Idiotype vaccination in MCL patients following Rituximab-containing chemotherapy induced tumor-specific T-cell immunity in the absence of B cells. Other immunotherapy, such as the combination of thalidomide with Rituximab, has shown substantial antitumor activity. A Phase I/II study is ongoing to determine the maximum tolerated dose (MTD) and the efficacy of lenalidomide in combination with Rituximab for relapsed/refractory MCL. This review summarizes the latest and exciting advances in MCL.