The role of cytotoxic therapy with hematopoietic stem cell transplantation in the treatment of follicular lymphoma: an evidence-based review

Personalized Autologous Stem Cell Harvesting Improves Patient Collection Outcomes

OBJECTIVES

This study aims to demonstrate that utilizing a personalized approach to apheresis stem cell collection, can safely optimize the collection outcomes, especially in the context of poor mobilizers and high cell targets.

BACKGROUND

The optimal mobilization and harvesting of peripheral blood stem cells is critical to the success of the stem cell transplant. The ideal strategy that promotes better cell yields, with sustainable use of resources and assuring patient safety, should be pursued.

METHODS

PBSC collections for autologous stem cell transplant data according to a fixed-processed volume strategy (One Size Fits All) or individualized to patients CD34+ peripheral blood content and target approach (Custom-Tailored or CT) were retrospectively compared.

RESULTS

A total of 263 collections from 142 patients were assessed. The majority of patients were male, had multiple myeloma and were mobilized with isolated G-CSF. The CT strategy promoted a significantly higher CD34+ cell yield when the pre-collection CD34 was lower than 20/µl (1.02 ± 0.16 versus 1.36 ± 0.23, p < 0.001) and also a decrease in the proportion of mobilization cycles that needed 3 apheresis (31% versus 14%, p = 0.02). There was no difference in apheresis-related adverse events between the groups.

CONCLUSION

Tailoring the apheresis procedures to the patient-specific characteristics and objectives, can effectively promote better patient outcome.

A critical assessment of dose effects of post-thaw CD34 on autologous stem cell transplantation treatment of haematological malignancies

A consensus threshold of pre-cryopreservation CD34-positive cells (CD34s) has been used as the minimum dose to initiate autologous stem cell transplantation (ASCT). Advances in cryopreservation posed a debate whether post-thaw CD34s might be a superior surrogate instead. We addressed the debate in this retrospective study of 217 adult ASCTs in five different haematological malignancies treated at a single centre. We showed that post-thaw CD34s was highly correlated with pre-cryopreservation CD34s (r = 0.97) and explained ∼2.2% (p = 0.003) of the variation of the post-thaw total nucleated cell viability that however had no power to predict engraftment outcomes. After stratifying the ASCT cases into four dose groups based on post-thaw CD34s reinfused, stepwise multivariate regression analyses detected significant effects in dose group and interactions with diseases for neutrophil and platelet recovery respectively. The significant dose effects and interactions were triggered by two technical outliers in the low dose group, and disappeared in the repeated regressions after exclusion of the outliers where disease and age were the significant predictors remained. Our data clearly support the validity of the consensus threshold in ASCT applications but also highlight neglected conditions where monitoring post-thaw CD34s and clinical attributes are valuable.

Hematopoietic Cell Transplantation, Version 2.2020, NCCN Clinical Practice Guidelines in Oncology

Hematopoietic cell transplantation (HCT) involves the infusion of hematopoietic progenitor cells into patients with hematologic disorders with the goal of re-establishing normal hematopoietic and immune function. HCT is classified as autologous or allogeneic based on the origin of hematopoietic cells. Autologous HCT uses the patient's own cells while allogeneic HCT uses hematopoietic cells from a human leukocyte antigen-compatible donor. Allogeneic HCT is a potentially curative treatment option for patients with certain types of hematologic malignancies, and autologous HCT is primarily used to support patients undergoing high-dose chemotherapy. Advances in HCT methods and supportive care in recent decades have led to improved survival after HCT; however, disease relapse and posttransplant complications still commonly occur in both autologous and allogeneic HCT recipients. Allogeneic HCT recipients may also develop acute and/or chronic graft-versus-host disease (GVHD), which results in immune-mediated cellular injury of several organs. The NCCN Guidelines for Hematopoietic Cell Transplantation focus on recommendations for pretransplant recipient evaluation and the management of GVHD in adult patients with malignant disease.

Comparison of Survival Between Autologous and Allogeneic Stem Cell Transplantation in Patients with Relapsed or Refractory B-Cell Non-Hodgkin Lymphoma: A Meta-Analysis

This study aimed to compare the efficacy of allogeneic stem cell transplantation (allo-SCT) versus autologous SCT (auto-SCT) in patients with relapsed or refractory B-cell non-Hodgkin lymphoma (B-NHL). Medline, CENTRAL, and EMBASE databases through December 31, 2019 were searched. The primary endpoints were overall survival (OS) and progression-free survival (PFS) rates. The secondary outcomes include transplant-related mortality (TRM), event-free survival, relapse/or progression, and nonrelapse mortality (NRM). The 18 retrospective studies enrolled 8,058 B-NHL patients (allo-SCT = 1,204; auto-SCT = 6,854). The OS was significantly higher in patients receiving auto-SCT than allo-SCT (pooled odds ratio [OR]: 1.69, 95% confidence interval [CI]: 1.29 to 2.22, P < 0.001), but no significant difference was found in PFS (pooled OR: 0.98, 95% CI: 0.69 to 1.38, P = 0.891). Auto-SCT patients also had lower TRM and NRM (TRM: OR = 0.23, P < 0.001; NRM: OR = 0.16, P < 0.001), but higher relapse or progression rate (OR = 2.37, P < 0.001) than allo-SCT patients. Subgroup analysis performed for different grades and subtypes of B-NHL showed higher OS in auto-SCT patients with high-grade B-NHL and diffused large B-cell lymphoma (DLBCL). There was, nevertheless, higher PFS in allo-SCT patients with low-grade B-NHL and follicular lymphoma (FL), and lower PFS in allo-SCT patients with DLBCL than their auto-SCT counterparts. In conclusion, the meta-analysis demonstrated that relapsed or refractory B-NHL patients who received auto-SCT have improved OS than those treated with allo-SCT, especially among those with DLBCL, but lower PFS among those with FL. However, the study is limited by a lack of randomized trials, patients’ heterogeneity, and possible selection bias.

Race/ethnicity and underlying disease influences hematopoietic stem/progenitor cell mobilization response: A single center experience

BACKGROUND

Whether race/ethnicity plays a role in hematopoietic stem/progenitor cells (HSPC) mobilization in autologous donors has not been studied. We hypothesize that donor characteristic including race/ethnicity, age, sex, body mass index, and diagnostic groups influences HSPC mobilization. Diagnostic groups include healthy allogeneic donors, autologous multiple myeloma (MM) and non-MM donors.

STUDY DESIGN AND METHODS

Here, we conducted a single-center retrospective study in 64 autologous patients and 48 allogeneic donors. Autologous donors were patients diagnosed with MM or non-MM. All donors were grouped as African American (AA), White (W), or "Other"(O).

RESULTS

Multivariate analysis demonstrated diagnostic group differences for CD34+ cell yields between race/ethnicity. Specifically, non-MM patients had the lowest CD34+ cell yields in AA and O, but not in W. For pre-apheresis peripheral blood (PB) CD34+ cell numbers, race/ethnicity had a significant effect both in bivariate and multivariate analyses. Non-MM patients had the lowest, and AA patients had the highest PB CD34+ cells. The results support the view that past therapies used in MM are likely more conducive of recovery of HSPC.

CONCLUSIONS

Our study shows that race/ethnicity and diagnostic group differences influenced CD34+ cell mobilization response across donor types. Interestingly, autologous MM donors with the aid of plerixafor displayed comparable CD34 yields to allogeneic donors. Even though both MM and non-MM donors received plerixafor, non-MM donors had significantly lower CD34 yields among AA and O donors but not in W donors. Larger studies would be required to validate the role of diagnostic groups and race/ethnicity interactions.

Indications for Hematopoietic Cell Transplantation and Immune Effector Cell Therapy: Guidelines from the American Society for Transplantation and Cellular Therapy

The American Society for Transplantation and Cellular Therapy (ASTCT) published its first white paper on indications for autologous and allogeneic hematopoietic cell transplantation (HCT) in 2015. It was identified at the time that periodic updates of indications would be required to stay abreast with state of the art and emerging indications and therapy. In recent years the field has not only seen an improvement in transplantation technology, thus widening the therapeutic scope of HCT, but additionally a whole new treatment strategy using modified immune effector cells, including chimeric antigen receptor T cells and engineered T-cell receptors, has emerged. The guidelines review committee of the ASTCT deemed it optimal to update the ASTCT recommendations for indications for HCT to include new data and to incorporate indications for immune effector cell therapy (IECT) where appropriate. The guidelines committee established a multiple stakeholder task force consisting of transplant experts, payer representatives, and a patient advocate to provide guidance on indications for HCT and IECT. This article presents the updated recommendations from the ASTCT on indications for HCT and IECT. Indications for HCT/IECT were categorized as (1) Standard of care, where indication is well defined and supported by evidence; (2) Standard of care, clinical evidence available, where large clinical trials and observational studies are not available but have been shown to be effective therapy; (3) Standard of care, rare indication, for rare diseases where demonstrated effectiveness exists but large clinical trials and observational studies are not feasible; (4) Developmental, for diseases where preclinical and/or early-phase clinical studies show HCT/IECT to be a promising treatment option; and (5) Not generally recommended, where available evidence does not support the routine use of HCT/IECT. The ASTCT will continue to periodically review these guidelines and update them as new evidence becomes available.

Stem cell mobilization kinetics in elderly patients with multiple myeloma

In this study, we aimed to investigate whether the procedure and product kinetics differ according to age groups in advanced-age MM patients who underwent autologous HSCT. 59 patients who underwent autologous HSCT were retrospectively analyzed. Then, the patients were divided into two groups as 60-65 years and ≥65 years. It was significantly lower in ≥65 years group (p = 0.008) and proportionally, the procedure duration was also significantly shortened in this group (p = 0.013). Total number of collected CD34 positive stem cells was 6.20 × 106 (±3.83) in 60-65 years group while it was 5.51 × 106 (±2.48) in ≥65 years group with no statistically significant difference (p = 0.825). In conclusion, there was no significant difference in terms of the number of collected CD34-positive stem cells in this study that investigates the mobilization data, procedure and product kinetics, we think that successful stem cell mobilization can be performed in appropriately selected patients regardless of age.

Stop and go: hematopoietic cell transplantation in the era of chimeric antigen receptor T cells and checkpoint inhibitors

PURPOSE OF REVIEW

For several decades, hematopoietic cell transplantation (HCT) has been considered the standard curative therapy for many patients with hematological malignancies. In addition to the cytotoxic effects of the chemotherapy and radiation used in the conditioning regimen, the benefits of HCT are derived from a reset of the immune system and harnessing the ability of donor T cells to eliminate malignant cells. With the dawn of the era of immunotherapies in the form of checkpoint inhibitors and chimeric antigen receptor (CAR) T cells, the role of HCT has evolved.

RECENT FINDINGS

Immunotherapy with checkpoint inhibitors is increasingly being used for relapsed Hodgkin and non-Hodgkin lymphoma after autologous HCT. Checkpoint inhibitors are also being tested after allogeneic HCT with observable benefits in treating hematological malignancies, but with a potential risk of increased graft versus host disease and transplant-related mortality. Immunotherapy with Cluster of differentiation 19 CAR T cells are powerful options with aggressive B-cell malignancies both for therapy and as induction leading to allogeneic HCT.

SUMMARY

Although immunotherapies with checkpoint inhibition and CAR T cells are increasingly being used to treat hematological malignancies, HCT remains a standard of care for most of the diseases with the best chance of cure. Combination of these therapies with HCT has the potential to more effectively treat hematological malignancies.

Relapse risk after autologous stem cell transplantation in patients with lymphoma based on CD34+ cell dose

It is unclear whether higher CD34 + cell doses infused for ASCT have any influence on survival or relapse in patients with lymphoma. We analyzed the correlation of infused CD34 + cell dose with relapse, survival, and hematopoietic recovery in 146 consecutive patients undergoing ASCT for lymphoma. Higher doses (>5 × 10⁶/kg) were significantly correlated with earlier hematopoietic recovery, fewer infectious episodes, lower transfusion needs. No differences were observed in lymphoma outcomes (4-year relapse incidence of 38% [95%CI: 29%-48%] in the lower dose group versus 51% [95%CI: 30%-69%] in the higher dose group, 10-year OS probabilities of 58% [95%CI: 48%-68%] versus 75% [95%CI: 59%-91%], 10-year DFS probabilities of 47% [95%CI: 37%-57%] versus 42% [95%CI: 23%-61%], p = NS for all outcomes). In this series, a higher infused CD34 + cell dose did not correlate with survival or relapse but correlated with earlier hematopoietic recovery and lower resource consumption.

The in vitro generation of multi-tumor antigen-specific cytotoxic T cell clones: Candidates for leukemia adoptive immunotherapy following allogeneic stem cell transplantation

Adoptive T-cell immunotherapy is a promising approach to manage and maintain relapse-free survival of leukemia patients, especially following allogeneic stem cell transplantation. Post-transplant adoptive immunotherapy using cytotoxic T lymphocytes (CTLs) of the donor origin provide graft-versus-tumor effects, with or without graft-versus-host disease. Myeloid leukemias express immunogenic leukemia associated antigens (LAAs); such as WT-1, PRAME, MAGE, h-TERT and others, most of them are able to induce specific T cell responses whenever associated with the proper co-stimulation. We investigated the ability of a LAA-expressing hybridoma cell line to induce CTL clones in PBMCs of HLA-matched healthy donors in vitro. The CTL clones were induced by repetitive co-culture with LAAs-expressing, HLA-A*0201(+) hybrid cell line, generated by fusion of leukemia blasts to human immortalized APC (EBV-sensitized B-lymphoblastoid cell line; HMy2). The induced cytotoxic T cell clones were phenotypically and functionally characterized by pentamer analysis, IFN-γ release ELISPOT and cellular cytotoxicity assays. All T cell lines showed robust peptide recognition and functional activity when sensitized with HLA-A*0201-restricted WT-1235-243, hTERT615-624 or PRAME100-108 peptides-pulsed T2 cells, in addition to partially HLA-matched leukemia blasts. This study demonstrates the feasibility of developing multi-tumor antigen-specific T cell lines in allogeneic PBMCs in vitro, using LAA-expressing tumor/HMy2 hybrid cell line model, for potential use in leukemia adoptive immunotherapy in partially matched donor-recipient setting.

Allogeneic hematopoietic stem cell transplantation in patients with advanced indolent lymphoproliferative disorders

BACKGROUND

The role of allogeneic hematopoietic stem cell transplantation for advanced indolent lymphoproliferative disorders remains to be established.

OBJECTIVE

This paper aims to describe the results of allogeneic hematopoietic stem cell transplantation in patients with advanced indolent lymphoproliferative disorders.

METHODS

This article reports on 29 adult patients submitted to allogeneic transplantations from 1997 to 2010.

RESULTS

Most had follicular non-Hodgkin lymphoma (n=14) or chronic lymphocytic leukemia (n=12). The median age was 44 years (range: 24-53 years) and 65% of patients were male. Only 21% had had access to rituximab and 45% to fludarabine. All had advanced disease (stage IV) with partial response or stable disease. Most underwent myeloablative conditioning n=17-59%). In this scenario, refractory disease was observed in seven (24%) patients, the 100-day mortality rate was 17% (n=5) and relapse occurred in four patients (18%). The main cause of death throughout the follow up was refractory disease in six of the 12 patients who died. Moderate and severe chronic graft-versus-host disease was frequent; about 41% of 24 patients analyzed. The overall survival rates and disease free survival at 42 months were 56.7% and 45.4%, respectively. According to Kaplan-Meyer analysis, the median time from diagnosis to transplant predicted the overall survival; however age, gender and conditioning regimen did not predict the prognosis. It was impossible to reach other conclusions because of the small sample size in this study.

CONCLUSIONS

The role of allogeneic transplantations should be re-evaluated in the era of targeted therapy.

Success of an International Learning Health Care System in Hematopoietic Cell Transplantation: The American Society of Blood and Marrow Transplantation Clinical Case Forum

The American Society for Blood and Marrow Transplantation (ASBMT) Clinical Case Forum (CCF) was launched in 2014 as an online secure tool to enhance interaction and communication among hematopoietic cell transplantation (HCT) professionals worldwide through the discussion of challenging clinical care issues. After 14 months, we reviewed clinical and demographical data of cases posted in the CCF from January 29, 2014 to March 18, 2015. A total of 137 cases were posted during the study period. Ninety-two cases (67%) were allogeneic HCT, 29 (21%) were autologous HCT, and in 16 (12%), the type of transplantation (autologous versus allogeneic) was still under consideration. The diseases most frequently discussed included non-Hodgkin lymphoma (NHL; n = 30, 22%), acute myeloid leukemia (n = 23, 17%), and multiple myeloma (MM; n = 20, 15%). When compared with the US transplantation activity reported by the US Department of Health and Human Services, NHL and acute lymphoblastic leukemia cases were over-represented in the CCF, whereas MM was under-represented (P < .001). A total of 259 topics were addressed in the CCF with a median of 2 topics/case (range, 1 to 6). Particularly common topics included whether transplantation was indicated (n = 57, 41%), conditioning regimen choice (n = 44, 32%), and post-HCT complications after day 100 (n = 43, 31%). The ASBMT CCF is a successful tool for collaborative discussion of complex cases in the HCT community worldwide and may allow identification of areas of controversy or unmet need from clinical, educational and research perspectives.

Hematopoietic progenitor cell mobilization for autologous transplantation - a literature review

The use of high-dose chemotherapy with autologous support of hematopoietic progenitor cells is an effective strategy to treat various hematologic neoplasms, such as non-Hodgkin lymphomas and multiple myeloma. Mobilized peripheral blood progenitor cells are the main source of support for autologous transplants, and collection of an adequate number of hematopoietic progenitor cells is a critical step in the autologous transplant procedure. Traditional strategies, based on the use of growth factors with or without chemotherapy, have limitations even when remobilizations are performed. Granulocyte colony-stimulating factor is the most widely used agent for progenitor cell mobilization. The association of plerixafor, a C-X-C Chemokine receptor type 4 (CXCR4) inhibitor, to granulocyte colony stimulating factor generates rapid mobilization of hematopoietic progenitor cells. A literature review was performed of randomized studies comparing different mobilization schemes in the treatment of multiple myeloma and lymphomas to analyze their limitations and effectiveness in hematopoietic progenitor cell mobilization for autologous transplant. This analysis showed that the addition of plerixafor to granulocyte colony stimulating factor is well tolerated and results in a greater proportion of patients with non-Hodgkin lymphomas or multiple myeloma reaching optimal CD34⁺ cell collections with a smaller number of apheresis compared the use of granulocyte colony stimulating factor alone.

Indications for Autologous and Allogeneic Hematopoietic Cell Transplantation: Guidelines from the American Society for Blood and Marrow Transplantation

Approximately 20,000 hematopoietic cell transplantation (HCT) procedures are performed in the United States annually. With advances in transplantation technology and supportive care practices, HCT has become safer, and patient survival continues to improve over time. Indications for HCT continue to evolve as research refines the role for HCT in established indications and identifies emerging indications where HCT may be beneficial. The American Society for Blood and Marrow Transplantation (ASBMT) established a multiple-stakeholder task force consisting of transplant experts, payer representatives, and a patient advocate to provide guidance on "routine" indications for HCT. This white paper presents the recommendations from the task force. Indications for HCT were categorized as follows: (1) Standard of care, where indication for HCT is well defined and supported by evidence; (2) Standard of care, clinical evidence available, where large clinical trials and observational studies are not available but HCT has been shown to be effective therapy; (3) Standard of care, rare indication, for rare diseases where HCT has demonstrated effectiveness but large clinical trials and observational studies are not feasible; (4) Developmental, for diseases where preclinical and/or early phase clinical studies show HCT to be a promising treatment option; and (5) Not generally recommended, where available evidence does not support the routine use of HCT. The ASBMT will periodically review these guidelines and will update them as new evidence becomes available.

Role of cytotoxic therapy with hematopoietic cell transplantation in the treatment of Hodgkin lymphoma: guidelines from the American Society for Blood and Marrow Transplantation

The role of hematopoietic cell transplantation (HCT) in the therapy of Hodgkin lymphoma (HL) in pediatric and adult patients is reviewed and critically evaluated in this systematic evidence-based review. Specific criteria were used for searching the published literature and for grading the quality and strength of the evidence and the strength of the treatment recommendations. Treatment recommendations based on the evidence are included and were reached unanimously by a panel of HL experts. Both autologous and allogeneic HCT offer a survival benefit in selected patients with advanced or relapsed HL and are currently part of standard clinical care. Relapse remains a significant cause of failure after both transplant approaches, and strategies to decrease the risk of relapse remain an important area of investigation.

Current therapeutic strategies and new treatment paradigms for follicular lymphoma

Follicular lymphoma (FL) is an indolent non-Hodgkin's lymphoma that remains an incurable disease for most patients. It is responsive to a variety of different treatments, however it follows a pattern of relapsing and remitting disease. Traditional therapeutic options for patients with untreated FL include expectant observation for asymptomatic and low tumor burden and multiagent cytotoxic chemotherapy for symptomatic and/or high tumor burden. Biologics have become an integral part of therapy with agents that target B lymphocytes, including monoclonal anti-CD20 antibodies and radiolabeled anti-CD20 antibodies. Treatment response to cytotoxic and biologic therapy is high initially; however, with subsequent treatments, response rate and remission duration typically decline and cumulative toxicities increase. The identification of novel targeted agents, use of stem cell transplantation, and new treatment combinations provide the opportunity to enhance patient outcomes. In this review, we critically examine standard treatment strategies for patients with newly diagnosed and relapsed or refractory FL and discuss established and emerging novel therapeutic approaches.

Mobilization and transplantation patterns of autologous hematopoietic stem cells in multiple myeloma and non-Hodgkin lymphoma

BACKGROUND

The mobilization of hematopoietic stem cells can be a limiting factor for transplantation, yet little is known about how the availability of novel mobilizing agents has affected the practices of oncologists and transplant specialists.

METHODS

US-based oncologists (n = 48) and transplant specialists (n = 46) were separately surveyed with a partial overlap of assessed information.

RESULTS

More transplant specialists than oncologists believed that the time between referral and first consultation is adequate (89.1% vs 54.2%; P < .001). The presence of comorbidities was the most common reason for patients not being referred for transplantation. Among oncologists, 31.3% avoided cyclophosphamide and 16.7% avoided lenalidomide to prevent mobilization impairment in patients with multiple myeloma (MM). Chemotherapy mobilization for MM was used by 23.9% of transplant specialists due to higher CD34+ yields and by 21.7% due to its anti-MM effect. In non-Hodgkin lymphoma (NHL), 26.1% of transplant specialists used chemotherapy mobilization due to higher CD34+ yields, and 26.1% collected hematopoietic stem cells on the rebound prior to chemotherapy. With regard to plerixafor use in MM, 36.9% of transplant specialists reported that they did not use it, and 28.3% said they reserved it for second mobilization. In NHL, 4.3% of transplant specialists reported not using plerixafor, and 39.1% reserved it for second mobilization.

CONCLUSIONS

Educational needs were identified to promote adequate referral for transplantation as well as successful and cost-effective methods for the mobilization of hematopoietic stem cells.

The prognostic impact of peripheral blood progenitor cell dose following high-dose therapy and autologous stem cell transplant for hematologic malignancies

High-dose chemotherapy (HDT) followed by autologous peripheral blood progenitor cell transplant (PBPCT) has become a standard intervention in certain clinical settings of hematologic malignancies, particularly multiple myeloma and relapsed/refractory lymphoma. While the minimal required PBPCs infused, as defined by number of CD34 + cells, has been relatively well delineated for adequate hematopoietic recovery post-HDT, optimal PBPC dose has not been clearly defined. This is particularly relevant in the context of retrospective data suggesting improved survival outcomes with increased PBPC doses. The potential confounding of these data as they relate to disease risk is discussed within this review. Additionally, other retrospective data have suggested that enhanced quantitative lymphocyte subset reconstitution post-HDT-PBPCT may confer progression-free and overall survival advantage. These reported series herein reviewed may inform discussion of future, prospective clinical trials with the intent of defining optimal autologous PBPC dose following HDT, especially as it may relate to metrics beyond hematopoietic recovery.

Indications for hematopoietic stem cell transplantation in patients with follicular lymphoma: a consensus project of the EBMT-Lymphoma Working Party

The aim of this project was to define indications for hematopoietic stem cell transplantation in follicular lymphoma in Europe. In the absence of evidence-based data, a RAND-modified Delphi procedure was used by an expert panel. After pre-defining statements, these were individually/anonymously scored by each participant using a 9-point scale. Consensus was reached that: 1) high-dose therapy with autologous stem cell rescue is not an appropriate option to consolidate first remission in patients responding to immuno-chemotherapy outside clinical trials; 2) in patients with first chemo-sensitive relapse, high-dose therapy with autologous stem cell rescue is an appropriate option to consolidate remission, especially in patients with a short response after immuno-chemotherapy or with high-risk FLIPI; 3) high-dose therapy with autologous stem cell rescue is also appropriate in second/subsequent chemo-sensitive relapses; 4) allotransplant (preferably a reduced intensity conditioning-allotransplant) should be considered at relapse after high-dose therapy with autologous stem cell rescue. No consensus was reached on the role of high-dose therapy with autologous stem cell rescue in low-risk first relapse, or on when an allotransplant should be preferred over high-dose therapy with autologous stem cell rescue. In the absence of evidence-based data, the consensus method used was a valuable tool to define indications for hematopoietic stem cell transplant in follicular lymphoma.

Successful hematopoietic stem cell collection in patients who fail initial plerixafor mobilization for autologous stem cell transplant

We report our experience of collecting stem cells in patients who failed to mobilize sufficient hematopoietic stem cell (HSC) using plerixafor (P) in the initial mobilization attempt. Twenty four patients were identified who failed a first mobilization attempt using P. Of these, 22 patients received granulocyte colony stimulating factor (G-CSF) and two patients received cyclophosphamide (CY) + G-CSF in combination with P for the initial attempt. The agents used for second collection attempt were granulocyte macrophage colony stimulating factor (GM-CSF) + G-CSF (19 patients), G-CSF + P (three patients), CY + G-CSF (one patient), and bone marrow harvest (one patient). A median of 0.6 × 10(6) CD34(+) cells/kg (range 0-1.97) were collected in the initial attempt. A second collection was attempted at a median of 22 days (range 15-127) after the first failed mobilization. The median CD34(+) cell dose collected with the second attempt was 1.1 × 10(6) CD34(+) cells/kg (range 0-7.2). A third collection was attempted in six patients at median of 51 days (range 34-163) after the first failed mobilization. These patients collected a median of 1.1 × 10(6) CD34(+) cells/kg (range 0-6.5). Total of 16 patients (67%) collected sufficient cells to undergo autologous stem cell transplant and eight patients (33%) were able to collect ≥2 × 10(6) CD34(+) cells/kg in a single subsequent attempt. Our experience suggests that a majority of patients who fail primary mobilization despite use of P can collect sufficient HSC with a subsequent attempt using combination of G-CSF with either P or GM-CSF.

Optimizing autologous stem cell mobilization strategies to improve patient outcomes: consensus guidelines and recommendations

Autologous hematopoietic stem cell transplantation (aHSCT) is a well-established treatment for malignancies such as multiple myeloma (MM) and lymphomas. Various changes in the field over the past decade, including the frequent use of tandem aHSCT in MM, the advent of novel therapies for the treatment of MM and lymphoma, and the addition of new stem cell mobilization techniques, have led to the need to reassess current stem cell mobilization strategies. Mobilization failures with traditional strategies are common and result in delays in treatment and increased cost and resource utilization. Recently, plerixafor-containing strategies have been shown to significantly reduce mobilization failure rates, but the ideal method to maximize stem cell yields and minimize costs associated with collection has not yet been determined. A panel of experts convened to discuss the currently available data on autologous hematopoietic stem cell mobilization and transplantation and to devise guidelines to optimize mobilization strategies. Herein is a summary of their discussion and consensus.

Outcomes of autologous or allogeneic stem cell transplantation for non-Hodgkin lymphoma

Transplant outcomes of autologous or allogeneic stem cell transplantation (SCT) have not been elucidated as a single cohort in non-Hodgkin lymphoma (NHL). We analyzed the outcomes of 270 adult recipients receiving autologous (auto) SCT (n = 198) or allogeneic (allo) SCT (n = 72) for NHL between the years 2000 and 2010. Five-year overall survival rates for B and T cell NHL were 58% and 50%, respectively (allo-SCT 51% vs. 54% for B and T-cell NHL, and auto-SCT 60% vs. 47% for B and T cell lymphoma, respectively). In multivariate analysis, the number of chemotherapy regimens and disease status pre-SCT were independently associated with long-term outcome after SCT (for both auto- and allo-SCT). We conclude that the type of transplantation offered to patients, based on patient selection and disease-related factors, can achieve long-term survival, highlighting the importance of further improvement in disease control and reducing procedure-related mortality. The role of transplantation needs to be reevaluated in the era of targeted therapy.

Just-in-time rescue plerixafor in combination with chemotherapy and granulocyte-colony stimulating factor for peripheral blood progenitor cell mobilization

Plerixafor, a recently approved peripheral blood progenitor cell mobilizing agent, is often added to granulocyte-colony stimulating factor (G-CSF) to mobilize peripheral blood progenitor cells in patients with lymphoma or myeloma who cannot mobilize enough CD34+ cells with G-CSF alone to undergo autologous stem cell transplantation. However, data are lacking regarding the feasibility and efficacy of just-in-time plerixafor in combination with chemotherapy and G-CSF. We reviewed the peripheral blood stem cell collection data of 38 consecutive patients with lymphoma (Hodgkin's and non-Hodgkin's) and multiple myeloma who underwent chemomobilization and high-dose G-CSF and just-in-time plerixafor to evaluate the efficacy of this treatment combination. All patients with multiple myeloma and all but one patient with lymphoma collected the minimum required number of CD34+ cells to proceed with autologous stem cell transplantation (>2 × 10(6) /kg of body weight). The median CD34+ cell dose collected in patients with non-Hodgkin lymphoma was 4.93 × 10(6) /kg of body weight. The median CD34+ cell dose collected for patients with multiple myeloma was 8.81 × 10(6) /kg of body weight. Plerixafor was well tolerated; no grade 2 or higher non-hematologic toxic effects were observed.

Outcomes and costs of autologous stem cell mobilization with chemotherapy plus G-CSF vs G-CSF alone

Chemotherapy plus G-CSF (C+G) and G-CSF alone are two of the most common methods used to mobilize CD34(+) cells for autologous hematopoietic SCT (AHSCT). In order to compare and determine the real-world outcomes and costs of these strategies, we performed a retrospective study of 226 consecutive patients at 11 medical centers (64 lymphoma, 162 multiple myeloma), of whom 55% of lymphoma patients and 66% of myeloma patients received C+G. Patients with C+G yielded more CD34(+) cells/day than those with G-CSF alone (lymphoma: average 5.51 × 10(6) cells/kg on day 1 vs 2.92 × 10(6) cells/kg, P=0.0231; myeloma: 4.16 × 10(6) vs 3.69 × 10(6) cells/kg, P<0.00001) and required fewer days of apheresis (lymphoma: average 2.11 vs 2.96 days, P=0.012; myeloma: 2.02 vs 2.83 days, P=0.0015), although nearly all patients ultimately reached the goal of 2 × 10(6) cells/kg. With the exception of higher rates of febrile neutropenia in myeloma patients with C+G (17% vs 2%, P<0.05), toxicities and other outcomes were similar. Mobilization with C+G cost significantly more (lymphoma: median $10,300 vs $7300, P<0.0001; myeloma: $8800 vs $5600, P<0.0001), although re-mobilization adds $6700 for drugs alone. Our results suggest that although both C+G and G-CSF alone are effective mobilization strategies, C+G may be more cost-effective for patients at high risk of insufficient mobilization.

Pharmacoeconomics of hematopoietic stem cell mobilization: an overview of current evidence and gaps in the literature

Adequate hematopoietic stem cell (HSC) mobilization and collection is required prior to proceeding with high dose chemotherapy and autologous hematopoietic stem cell transplant. Cytokines such as G-CSF, GM-CSF, and peg-filgrastim, alone or in combination with plerixafor, and after chemotherapy have been used to mobilize HSCs. Studies have shown that the efficiency of HSC mobilization and collection may vary when different methods of mobilization are used. No studies have shown that survival is significantly affected by the method of mobilization, but some studies have suggested that cost and resource utilization may be different between different mobilization techniques. After the FDA approval of plerixafor with G-CSF to mobilize HSCs many transplant centers became concerned about the cost of HSC mobilization. A panel of experts was convened ant this paper reviews the current literature on the pharmacoeconomics of HSC mobilization.

SIE, SIES, GITMO revised guidelines for the management of follicular lymphoma

By using the GRADE system, we updated the guidelines for management of follicular cell lymphoma issued in 2006 from SIE, SIES, and GITMO group. We confirmed our recommendation to frontline chemoimmunotherapy in patients with Stage III-IV disease and/or high tumor burden. Maintenance rituximab was also recommended in responding patients. In patients relapsing after an interval longer than 12 months from frontline therapy, we recommended chemoimmunotherapy with non cross-resistant regimens followed by rituximab maintenance. High dose chemotherapy followed by hematopoietic stem cell transplant was recommended for young fit patients who achieve a response after salvage chemoimmunotherapy.

Update on the role of autologous hematopoietic stem cell transplantation in follicular lymphoma

Follicular lymphoma (FL) remains incurable despite advances in new strategies of treatment, including monoclonal antibodies (MoAb). Except for early stages, FL is characterized by responses to treatments and systematic relapses. The main objective in this disease is to achieve a better progression free survival (PFS) and to increase overall survival (OS), mainly in young patients. In order to improve the results of conventional chemotherapy, autologous stem cell transplant (ASCT) is a feasible treatment in these patients. In this moment, ASCT is not recommended as first line treatment, except for transformed FL, but is a good strategy as salvage therapy with an improved PFS and OS. New drugs have been introduced to enhance responses of ASCT, but nowadays they are not part of conventional conditioning regimen.

Diagnosis and treatment of follicular lymphoma: where do we stand?

SUMMARY The treatment of follicular lymphoma (FL) has advanced in the past decade. The routine use of monoclonal antibodies, arrival of bendamustine and application of radioimmunotherapy have ushered in major improvement in response rates for patients with indolent lymphoma. Studies have documented an improvement in progression-free survival and overall survival with chemoimmunotherapy followed by maintenance rituximab. The purpose of this review is to share an overview of recent advances in clinical care and research underway that will be incorporated into clinical practice in the foreseeable future. We will restrict our review to FL because the wide variety of types of indolent lymphoma makes it impossible to cover all of them in a brief review. FL is the most common indolent lymphoma and the general approach to diagnosis and treatment of this disease is often utilized as a foundation for the diagnosis and treatment of indolent lymphomas in general.

Controversies and recent advances in hematopoietic cell transplantation for follicular non-hodgkin lymphoma

Commonly designated as an indolent non-Hodgkin lymphoma, follicular lymphoma (FL) presents with striking pathobiological and clinical heterogeneity. Initial management strategies for FL have evolved to involve combination chemoimmunotherapy and/or radio-immunoconjugates. Unfortunately even with the best available nontransplant treatment, which nowadays results in higher frequency of response, FL remains incurable. Although considered a feasible therapeutic option, the use of hematopoietic cell transplantation (HCT) remains controversial. The appropriate timing, graft source, and intensity of HCT conditioning regimens in FL are often matters of debate. Herein we review the available published data pertaining to the use of autologous or allogeneic HCT in patients with FL across different stages of the disease, discuss major recent advances in the field, and highlight avenues for future research. The current literature does not support a role of HCT for FL in first remission, but in the relapsed setting autologous HCT remains appropriate for patients with early chemosensitive relapses, while allogeneic transplantation remains the sole curative modality for this disease, in relatively younger patients without significant comorbidities.

Comparison of outcomes after allogeneic hematopoietic stem cell transplantation in patients with follicular lymphoma, diffuse large B-cell lymphoma associated with follicular lymphoma, or de novo diffuse large B-cell lymphoma

The outcome after allogeneic hematopoietic stem cell transplantation (allo-HCT) for diffuse large B-cell lymphoma (DLBCL) associated with follicular lymphoma (FL), which includes DLBCL with pre- or co-existing FL, remains controversial, and few previous reports have compared the outcomes after allo-HCT for FL, DLBCL associated with FL, and de novo DLBCL. We retrospectively analyzed 97 consecutive patients with FL (n = 46), DLBCL associated with FL (n = 22), or de novo DLBCL (n = 29) who received allo-HCT at our institute between 2000 and 2010. With a median follow-up of 53 months, the 5-year overall survival (OS) and progression-free survival (PFS) were, respectively, 77% and 70% for FL, 62% and 57% for DLBCL associated with FL, and 26% and 23% for de novo DLBCL. The 5-year cumulative incidences of non-relapse mortality and disease progression/relapse were, respectively, 16% and 15% for FL, 19% and 24% for DLBCL associated with FL, and 36% and 41% for de novo DLBCL. By a multivariate analysis, the OS and PFS for DLBCL associated with FL were significantly better than those for de novo DLBCL, whereas they were not significantly different from those for FL. These results suggest that allo-HCT may be a promising option for patients with not only advanced FL but also DLBCL associated with FL.

High-dose therapy with autologous stem cell transplantation versus chemotherapy or immuno-chemotherapy for follicular lymphoma in adults

BACKGROUND

Follicular lymphoma (FL) is the most common indolent and second most common Non-Hodgkin`s lymphoma (NHL) in the Western world. Standard treatment usually includes rituximab and chemotherapy. High-dose therapy (HDT) followed by autologous stem cell transplantation (ASCT) is an option for patients in advanced stages or for second-line therapy, leading to improved progression-free survival (PFS) rates. However, the impact of HDT and ASCT remains unclear, as there are hints of an increased risk of second cancers.

OBJECTIVES

We performed a systematic review with meta-analysis of randomised controlled trials (RCTs) comparing HDT plus ASCT with chemotherapy or immuno-chemotherapy in patients with FL with respect to overall survival (OS), PFS, treatment-related mortality (TRM), adverse events and secondary malignancies.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and EMBASE as well as conference proceedings from January 1985 to September 2011 for RCTs. Two review authors independently screened search results.

SELECTION CRITERIA

Randomised controlled trials comparing chemotherapy or immuno-chemotherapy with HDT followed by ASCT in adults with previously untreated or relapsed FL.

DATA COLLECTION AND ANALYSIS

We used hazard ratios (HR) as effect measures used for OS and PFS as well as relative risks for response rates. Two review authors independently extracted data and assessed the quality of trials.

MAIN RESULTS

Our search strategies led to 3046 potentially relevant references. Of these, five RCTs involving 1093 patients were included; four trials in previously untreated patients and one trial in relapsed patients. Overall, the quality of the five trials is judged to be moderate. All trials were reported as randomised and judged to be open-label studies, because usually trials evaluating stem cell transplantation are not blinded. Due to the small number of studies in each analysis (four or less), the quantification of heterogeneity was not reliable and not evaluated in further detail. A potential source of bias are uncertainties in the HR calculation. For OS, the HR had to be calculated for three trials from survival curves, for PFS for two trials.We found a statistically significant increased PFS in previously untreated FL patients in the HDT + ASCT arm (HR = 0.42 (95% confidence interval (CI) 0.33 to 0.54; P < 0.00001). However, this effect is not transferred into a statistically significant OS advantage (HR = 0.97; 95% 0.76 to 1.24; P = 0.81). The subgroup of trials adding rituximab to both intervention arms (one trial) confirms these results and the trial had to be stopped early after an interim analysis due to a statistically significant PFS advantage in the HDT + ASCT arm (PFS: HR = 0.36; 95% CI 0.23 to 0.55; OS: HR = 0.88; 95% CI 0.40 to 1.92). In the four trials in previously untreated patients there are no statistically significant differences between HDT + ASCT and the control-arm in terms of TRM (RR = 1.28; 95% CI 0.25 to 6.61; P = 0.77), secondary acute myeloid leukaemia/myelodysplastic syndromes (RR = 2.87; 95% CI 0.7 to 11.75; P = 0.14) or solid cancers (RR = 1.20; 95% CI 0.25 to 5.77; P = 0.82). Adverse events were rarely reported and were observed more frequently in patients undergoing HDT + ASCT (mostly infections and haematological toxicity).For patients with relapsed FL, there is some evidence (one trial, N = 70) that HDT + ASCT is advantageous in terms of PFS and OS (PFS: HR = 0.30; 95% CI 0.15 to 0.61; OS: HR = 0.40; 95% CI 0.18 to 0.89). For this trial, no results were reported for TRM, adverse events or secondary cancers.

AUTHORS' CONCLUSIONS

In summary, the currently available evidence suggests a strong PFS benefit for HDT + ASCT compared with chemotherapy or immuno-chemotherapy in previously untreated patients with FL. No statistically significant differences in terms of OS, TRM and secondary cancers were detected. These effects are confirmed in a subgroup analysis (one trial) adding rituximab to both treatment arms. Further trials evaluating this approach are needed to determine this effect more precisely in the era of rituximab. Moreover, longer follow-up data are necessary to find out whether the PFS advantage will translate into an OS advantage in previously untreated patients with FL.There is evidence that HDT + ASCT is advantageous in patients with relapsed FL.

Stem cell transplantation for indolent lymphoma: a reappraisal

Allogeneic transplantation is established as a curative treatment for follicular lymphoma, but with considerable short and long-term morbidity and mortality. Data and controversies regarding conditioning regimen, donor source, GVHD prophylaxis, post transplant interventions and approaches to predict and reduce morbidity and mortality are reviewed. Total body irradiation is very effective but toxic and reduced intensity conditioning is often preferred though associated with somewhat higher rates of recurrence. The risk of chronic GVHD and its late sequelae can be markedly reduced by in-vivo T-cell depletion using alemtuzumab but also leads to somewhat higher incidence of disease recurrence. When using such treatment strategies, one can consider prophylactic or preemptive donor lymphocyte infusions or low toxicity medical treatment such as rituximab. Overall the long term outcomes, particularly survival and current progression free survival of patients undergoing allogeneic transplantation for indolent lymphoma have steadily improved and transplant can now often safely be considered up to the sixth decade of life. Outcomes of unrelated donor transplantation approach those of HLA-identical sibling transplant and even mismatched umbilical cord transplant can be considered in selected patients. The assessment of risks and benefits is aided by the use of various novel tools.

Treatment options for transformed lymphoma: incorporating allogeneic stem cell transplantation in a multimodality approach

Transformed non-Hodgkin lymphoma (TL) arising from follicular lymphoma carries a poor prognosis, and the median survival time after transformation is approximately 10 to 12 months. Standard chemotherapy and radioimmunotherapy have offered promising responses; however, the duration of response does not appear to last long. Several studies evaluating the role of autologous stem cell transplantation (auto-SCT) as a salvage regimen have been reported, and a subset of patients benefit from this modality of treatment. With an improvement in supportive care, outcome after allogeneic stem cell transplantation (allo-SCT) has been improved significantly over past decades; however, very limited data are available for TL. In the era of emerging novel therapies, the actual timing, optimal conditioning regimens, and long-term impact of the type of stem cell transplantation (auto-SCT vs allo-SCT) is unclear. This review addresses the approaches to the management of patients with TL.

The role of cytotoxic therapy with hematopoietic stem cell transplantation in the treatment of adult acute lymphoblastic leukemia: update of the 2006 evidence-based review

Clinical research published since the first evidence-based review on the role of hematopoietic stem cell transplantation (SCT) in the treatment of acute lymphoblastic leukemia (ALL) in adults is presented and critically evaluated in this update. Treatment recommendations changed or modified based on new evidence include: (1) myeloablative allogeneic SCT is an appropriate treatment for adult (<35 years) ALL in first complete remission for all disease risk groups; and (2) reduced-intensity conditioning may produce similar outcomes to myeloablative regimens. Treatment recommendations unchanged or strengthened by new evidence include: (1) allogeneic SCT is recommended over chemotherapy for ALL in second complete remission or greater; (2) allogeneic is superior to autologous SCT; and (3) there are similar survival outcomes after related and unrelated allogeneic SCT. New treatment recommendations based on new evidence include: (1) in the absence of a suitable allogeneic donor, autologous SCT may be an appropriate therapy, but results in a high relapse rate; (2) it is appropriate to consider cord blood transplantation for patients with no HLA well-matched donor; and (3) imatinib therapy before and/or after SCT (for Ph+ ALL) yields significantly superior survival outcomes. Areas of needed research in the treatment of adult ALL with SCT were identified and presented in the review.

The role of cytotoxic therapy with hematopoietic stem cell transplantation in the treatment of adult acute lymphoblastic leukemia: update of the 2006 evidence-based review

Clinical research published since the first evidence-based review on the role of hematopoietic stem cell transplantation (SCT) in the treatment of acute lymphoblastic leukemia (ALL) in adults is presented and critically evaluated in this update. Treatment recommendations changed or modified based on new evidence include: (1) myeloablative allogeneic SCT is an appropriate treatment for adult (<35 years) ALL in first complete remission for all disease risk groups; and (2) reduced-intensity conditioning may produce similar outcomes to myeloablative regimens. Treatment recommendations unchanged or strengthened by new evidence include: (1) allogeneic SCT is recommended over chemotherapy for ALL in second complete remission or greater; (2) allogeneic is superior to autologous SCT; and (3) there are similar survival outcomes after related and unrelated allogeneic SCT. New treatment recommendations based on new evidence include: (1) in the absence of a suitable allogeneic donor, autologous SCT may be an appropriate therapy, but results in a high relapse rate; (2) it is appropriate to consider cord blood transplantation for patients with no HLA well-matched donor; and (3) imatinib therapy before and/or after SCT (for Ph+ ALL) yields significantly superior survival outcomes. Areas of needed research in the treatment of adult ALL with SCT were identified and presented in the review.

High-dose cyclophosphamide and rituximab without stem cell transplant: a feasibility study for low grade B-cell, transformed and mantle cell lymphomas

Relapse after autologous stem cell transplant for low grade B-cell lymphoma is common secondary to ineffective conditioning and/or tumor autograft contamination. We investigated high-dose cyclophosphamide and rituximab without stem cell rescue as first-line or salvage therapy in lymphomas. After establishing safety, accrual was increased to evaluate event-free survival (EFS). Eighty-one adults received rituximab (375 mg/m(2) days 1, 4, 8, 11, 45, 52), cyclophosphamide (50 mg/kg days 15-18), and pegfilgrastim (day 20). Forty-two patients had low grade B-cell lymphoma [grade I/II follicular (69%), transformed lymphoma (17%), other (15%)]: 45% were treated without measurable disease. Thirty-nine patients had mantle cell lymphoma: 82% were treated without measurable disease. All achieved hematopoietic recovery; 46% required brief hospitalizations. The 5-year EFS and overall survival (OS) for patients with low grade B-cell and transformed lymphoma were 40% and 72%, respectively. The 5-year EFS and OS for patients with MCL were 39% and 62%, respectively. This low-toxicity therapeutic approach obviates the need for stem cell products and establishes a platform for future therapies.

Histology and time to progression predict survival for lymphoma recurring after reduced-intensity conditioning and allogeneic hematopoietic cell transplantation

Reduced-intensity conditioning (RIC) before allogeneic hematopoietic cell transplantation (HCT) is increasingly used as a potentially curative option for patients with advanced lymphoma; however, relapse remains a major challenge. Unfortunately, little data are available on outcomes, predictors of survival, and results of specific management strategies in these patients. In the present study, a total of 101 consecutive relapses occurred and were evaluated in 280 patients with lymphoma who underwent RIC HCT. Diseases included aggressive non-Hodgkin lymphoma (NHL) (n = 42), indolent NHL (n = 33), and Hodgkin lymphoma (HL) (n = 26). Median time to relapse was 90 days (range, 3-1275 days), and graft-versus-host disease at relapse was present in 56 patients (55%). Interventions after relapse included no therapy (n = 14), withdrawal of immunosuppression alone (n = 11), chemoradiotherapy (n = 60), and donor lymphocyte infusion/second HCT (n = 16). Overall survival (OS) was 33% (95% confidence interval [CI], 23%-44%) at 3 years after relapse and 23% (95% CI, 13%-34%) at 5 years after relapse. Both aggressive NHL (vs indolent disease; hazard ratio, 2.29; P = .008) and relapse within 1 month post-HCT (vs >6 months; hazard ratio, 3.17; P = .004) were associated with increased mortality. Estimated 3-year OS was 16% (95% CI, 5%-32%) after relapse for aggressive NHL, 40% (95% CI, 19%-61%) after relapse for indolent NHL, and 47% (95% CI, 29%-64%) after relapse for HL. The 1-year survival was 24% for patients relapsing within 1 month post-HCT, compared with 52% for those relapsing at 1-3 months, 74% for those relapsing at 3-6 months, and 77% for those relapsing at more than 6 months. We conclude that despite relapse of lymphoma after RIC HCT, some patients may experience prolonged survival, with better postrelapse outcomes occurring in patients with indolent NHL, HL, or late relapse.