The evolving role of autologous and allogeneic stem cell transplantation in follicular lymphoma

Efficacy of Pharmacokinetics-Directed Busulfan, Cyclophosphamide, and Etoposide Conditioning and Autologous Stem Cell Transplantation for Lymphoma: Comparison of a Multicenter Phase II Study and CIBMTR Outcomes

Busulfan, cyclophosphamide, and etoposide (BuCyE) is a commonly used conditioning regimen for autologous stem cell transplantation (ASCT). This multicenter, phase II study examined the safety and efficacy of BuCyE with individually adjusted busulfan based on preconditioning pharmacokinetics. The study initially enrolled Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) patients ages 18 to 80 years but was amended due to high early treatment-related mortality (TRM) in patients > 65 years. BuCyE outcomes were compared with contemporaneous recipients of carmustine, etoposide, cytarabine, and melphalan (BEAM) from the Center for International Blood and Marrow Transplant Research. Two hundred seven subjects with HL (n = 66) or NHL (n = 141) were enrolled from 32 centers in North America, and 203 underwent ASCT. Day 100 TRM for all subjects (n = 203), patients > 65 years (n = 17), and patients ≤ 65 years (n = 186) were 4.5%, 23.5%, and 2.7%, respectively. The estimated rates of 2-year progression-free survival (PFS) were 33% for HL and 58%, 77%, and 43% for diffuse large B cell lymphoma (DLBCL; n = 63), mantle cell lymphoma (MCL; n = 29), and follicular lymphoma (FL; n = 23), respectively. The estimated rates of 2-year overall survival (OS) were 76% for HL and 65%, 89%, and 89% for DLBCL, MCL, and FL, respectively. In the matched analysis rates of 2-year TRM were 3.3% for BuCyE and 3.9% for BEAM, and there were no differences in outcomes for NHL. Patients with HL had lower rates of 2-year PFS with BuCyE, 33% (95% CI, 21% to 46%), than with BEAM, 59% (95% CI, 52% to 66%), with no differences in TRM or OS. BuCyE provided adequate disease control and safety in B cell NHL patients ≤ 65 years but produced worse PFS in HL patients when compared with BEAM.

Comparison of non-myeloablative conditioning regimens for lymphoproliferative disorders

Hematopoietic cell transplantation (HCT) with non-myeloablative conditioning (NMA) for lymphoproliferative diseases (LD) includes fludarabine with and without low-dose total body irradiation (TBI). Transplant outcomes were compared among patients ≥40 years with LD who received a HCT with TBI (N=382) and no-TBI (N=515) NMA from 2001 to 2011. The groups were comparable except for donor, graft, prophylaxis for graft-versus-host disease (GVHD), disease status and year of HCT. Cumulative incidences of grades II–IV GVHD at 100 days, were 29% and 20% (p=0.001), and chronic GVHD at 1 year were 54% and 44% (p=0.004) for TBI and no-TBI, respectively. Multivariate analysis of progression/relapse, treatment failure and mortality showed no outcome differences by conditioning. Full donor chimerism at day 100 was observed in 82% vs. 64% in the TBI and no-TBI groups, respectively (p=0.006). Subset of four most common conditioning/ GVHD prophylaxis combinations demonstrated higher rates of grades II–IV acute (p<0.001) and chronic GVHD (p<0.001) among recipients of TBI-mycophenolate mofetil (MMF) compared to other combinations. TBI-based NMA conditioning induces faster full donor chimerism but overall survival outcomes are comparable to no-TBI regimens. Combination of TBI and MMF are associated with higher rates of GVHD without impact on survival outcomes in patients with LD.

Prognostic tools in follicular lymphomas

Despite significant improvements in treatment modalities over the 10 years, the clinical course of patients with follicular lymphoma (FL) remains heterogeneous. Thus, prognostic indexes are still required to direct treatment choices and for the design of clinical trials. Investigators have conducted a variety of studies aimed at integrated assessment of biological and clinical features in order to identify novel prognostic factors and scoring systems. Genetic studies focused on tumor cells and the tumor microenvironment represent a step forward in understanding the biology of FL and are likely to provide new prognostic tools for future clinical use. Several prognostic factors have been identified and are currently used in combination to establish prognostic scores and to support therapeutic decisions. The FL International Prognostic Index (FLIPI) is currently used for defining individual risk of death. More recently, FLIPI2 was developed by the same group that built FLIPI as a new model for prognostic definition of patients with FL. The model was defined using prospectively collected data from patients who also received the monoclonal therapeutic antibody rituximab and stratifies patients into three risk categories for disease progression. Since many biological factors are not yet clinically validated or easily assessable, clinical data still represent the major source of prognostic information. The progressive development of new and more effective therapies for the treatment of FL makes the study of prognosis a dynamic and evolving area of clinical research.

The role of rituximab in autologous and allogeneic hematopoietic stem cell transplantation for non-Hodgkin's lymphoma

The addition of rituximab to chemotherapy has substantially changed the treatment strategies for patients with B-cell lymphomas. Rituximab, combined with standard chemotherapy regimens, shows consistently improved results compared with chemotherapy alone and has been extensively employed in both newly diagnosed and relapsed patients with B-cell lymphoma. Because of its low toxicity profile and its potent antilymphoma activity mediated through direct apoptotic and indirect effector mechanisms, rituximab also has been actively incorporated into stem cell transplantation (SCT) protocols to attain a state of minimal disease, provide a safe and effective method for in vivo purging prior to autologous SCT, and promote graft-versus-lymphoma effects in allogeneic SCT. This review compiles the still immature but rapidly growing data on this combined modality.

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.

Second hematopoietic SCT for lymphoma patients who relapse after autotransplantation: another autograft or switch to allograft?

Although autologous hematopoietic SCT (auto-HSCT) is the only potentially curative treatment for lymphoma that has relapsed after conventional chemotherapy, the prognosis of patients with disease recurrence after auto-HSCT is poor. Some highly selected patients can benefit from second transplants. One-third with late recurrence after initial auto-HSCT may attain a prolonged remission after second auto-HSCT. Non-myeloablative or reduced-intensity conditioning (RIC) allogeneic hematopoietic SCT (allo-HSCT) has been used successfully after auto-HSCT failures, especially in subjects who have an HLA-compatible donor, chemosensitive disease and good performance status. Patients with chemosenstive disease recurrence who have completed at least 1 year after their first auto-HSCT should be considered for a second auto-HSCT. Patients who have chemoresistant disease are best served by participation in a well-designed clinical trial examining novel antitumor agents.

Unrelated donor hematopoietic cell transplantation for non-hodgkin lymphoma: long-term outcomes

We analyzed the outcomes of 283 patients receiving unrelated donor allogeneic hematopoietic cell transplantation for non-Hodgkin lymphoma (NHL) facilitated by the Center for International Blood and Marrow Transplant Research/National Marrow Donor Program (CIBMTR/NMDP) between 1991 and 2004. All patients received myeloablative conditioning regimens. The median follow-up of survivors is 5 years. Seventy-three (26%) patients are alive. The day 100 probability of death from all causes is estimated at 39%. The cumulative incidence of developing grade III-IV acute graft-versus-host disease (aGVHD) at day 100 is 25%. The estimated 5-year survival and failure free survival are 24% (95% confidence interval [CI]: 19-30) and 22% (95% CI: 17-28), respectively. Factors adversely associated with overall survival (OS) included increasing age, decreased performance status, and refractory disease. Follicular lymphoma (FL) and peripheral T cell lymphoma had improved survival compared to aggressive B cell lymphomas. Factors adversely associated with progression-free survival (PFS) included performance status, histology, and disease status at transplant. Long-term failure-free survival is possible following unrelated donor transplantation for NHL, although early mortality was high in this large cohort.

Rituximab improves the efficacy of high-dose chemotherapy with autograft for high-risk follicular and diffuse large B-cell lymphoma: a multicenter Gruppo Italiano Terapie Innnovative nei linfomi survey

PURPOSE

To investigate the impact of adding rituximab to intensive chemotherapy with peripheral-blood progenitor cell (PBPC) autograft for high-risk diffuse large B-cell lymphoma (DLB-CL) and follicular lymphoma (FL).

PATIENTS AND METHODS

Data were collected from 10 centers associated with Gruppo Italiano Terapie Innnovative nei Linfomi for 522 patients with DLB-CL and 223 patients with FL (median age, 47 years) who received the original or a modified high-dose sequential (HDS) chemotherapy regimen. HDS was delivered to 396 patients without (R-) and to 349 patients with (R+) rituximab; 154 (39%) and 178 patients (51%) in the R- and R+ subsets, respectively, underwent HDS for relapsed/refractory disease.

RESULTS

A total of 355 R- (90%) and 309 R+ patients (88%) completed the final PBPC autograft. Early treatment-related mortality was 3.3% for R- and 2.8% for R+ (P = not significant). Two parameters significantly influenced the outcome: disease status at HDS, with 5-year overall survival (OS) projections of 69% versus 57% for diagnosis versus refractory/relapsed status, respectively, and rituximab addition, with 5-year OS of 69% versus 60% in the R+ versus R- groups, respectively. In the multivariate analysis, these two variables maintained an independent prognostic value. The marked benefit of rituximab was evident in patients receiving HDS as salvage treatment: the 5-year OS projections for R+ versus R- were, respectively, 64% versus 38%, for patients with refractory disease or early relapse and 71% versus 57%, for patients with late relapse, partial response, or second/third relapse.

CONCLUSION

The results of this large series indicate that rituximab should be included in the current practice of PBPC autograft for DLB-CL and FL.

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.

Cladribine combined with cyclophosphamide and mitoxantrone is an active salvage therapy in advanced non-Hodgkin's lymphoma

The aim of this study was to determine the feasibility, efficacy and toxicity of the combined therapy consisting of cladribine (2-CdA), mitoxantrone and cyclophosphamide (CMC regimen) in patients with refractory or relapsed non-Hodgkin's lymphoma (NHL). Thirty six patients, 14 with mantle cell lymphoma (MCL), 10 with diffuse large B-cell lymphoma (DLBCL), 5 with follicular lymphoma (FL), 3 with small lymphocytic lymphoma (SLL), and 4 with T-cell lymphoma were enrolled to the study. The CMC protocol consisted of 2-CdA at a dose of 0.12 mg/kg in a 2-hour infusion on days 1 through 3, mitoxantrone 10 mg/m(2) i.v. on day 1 and cyclophosphamide 650 mg/m(2) i.v. on day 1. The CMC courses were repeated at intervals of 4 weeks. Thirty three patients were available for evaluation of response. Overall response rate (OR) was 58% (95% CI, 41--75%). Seven patients (21%; 95% CI, 7--35%) achieved a complete response (CR) and 12 patients (36%; 95% CI, 20--52%) achieved a partial response (PR). Seven of 19 patients with CR/PR are still in remission with a median follow-up of 3 months (range, 2-17 months). The median failure-free survival (FFS) was 5 months (range, 2-17 months). The median overall survival (OS) for the entire group was 9 months (range, 0.1-7 months). There was a significant difference in OS between responders and nonresponders after CMC therapy (log rank test, P = 0.015). When different disease status before CMC treatment was considered, a trend toward longer survival of recurrent patients was observed (log rank test, P = 0.08). Grade 3-4 neutropenia developed in 14 (39%) patients, and 16 episodes (15%) of grade 3-4 infections were observed. Grade 3-4 thrombocytopenia or anemia was seen in 9 patients (25%) and 10 patients (28%), respectively. The results of our study show that the CMC regimen is effective salvage therapy with acceptable toxicity in heavily pretreated patients with NHL including MCL and DLBCL.

Stem cell transplantation with reduced-intensity conditioning regimens: a review of ten years experience with new transplant concepts and new therapeutic agents

The realization in the 1990s that allogeneic stem cell transplants (SCT) have a potentially curative graft-versus-leukemia (GVL) effect in addition to the antileukemic action of myeloablative conditioning regimens was a major stimulus for the development of reduced-intensity conditioning (RIC) regimens, aimed primarily at securing engraftment to provide the GVL effect, while minimizing regimen-related toxicity. It is now over 10 years since RIC regimens were heralded as a new direction in the field of SCT. Over the last decade much has been learned about the ways in which the conditioning regimen can be tailored to provide adequate immunosuppression, and modulated to deliver a chosen degree of antimalignant treatment. The huge literature of clinical data with RIC transplantation now permits us to more clearly define the success and limitations of the approach. This review examines the origins of RIC SCT, explores the degree to which the initial expectations and purpose of the approach have been realized, and outlines some ways forward for the field.