Autologous versus reduced-intensity allogeneic hematopoietic cell transplantation for patients with chemosensitive follicular non-Hodgkin lymphoma beyond first complete response or first partial response

Clinical Practice Recommendations for Hematopoietic Cell Transplantation and Cellular Therapies in Follicular Lymphoma: A Collaborative Effort on Behalf of the American Society for Transplantation and Cellular Therapy and the European Society for Blood and Marrow Transplantation

Follicular lymphoma (FL) is the most common indolent B-cell non-Hodgkin lymphoma (NHL), accounting for nearly one-third of all NHL. The therapeutic landscape for patients with FL has significantly expanded over the past decade, but the disease continues to be considered incurable. Hematopoietic cell transplantation (HCT) is potentially curative in some cases. Recently, the emergence of chimeric antigen receptor T-cell therapy (CAR-T) for patients with relapsed/refractory (R/R) FL has yielded impressive response rates and long-term remissions, but definitive statement on the curative potential of CAR-T is currently not possible due to limited patient numbers and relatively short follow up. A consensus on the contemporary role, optimal timing, and sequencing of HCT (autologous or allogeneic) and cellular therapies in FL is needed. As a result, the American Society of Transplantation and Cellular Therapy (ASTCT) Committee on Practice Guidelines endorsed this effort to formulate consensus recommendations to address this unmet need. The RAND-modified Delphi method was used to generate 15 consensus statements/recommendations. These clinical practice recommendations will help guide clinicians managing patients with FL. Of note, the use of bispecific antibodies in R/R FL was not in the scope of this project.

The unnecessary use of short tandem repeat testing on bone marrow samples in patients after 1 year following allogeneic hematopoietic stem cell transplant

OBJECTIVES

To determine whether the information provided by short tandem repeat (STR) testing and bone marrow (BM) biopsy specimens following hematopoietic stem cell transplant (HSCT) provides redundant information, leading to test overutilization, without additional clinical benefit.

METHODS

Cases with synchronous STR and flow cytometric immunophenotyping (FCI) testing, as part of the BM evaluation, were assessed for STR/FCI concordance.

RESULTS

Of 1199 cases (410 patients), we found the overall concordance between STR and FCI was 93%, with most cases (1063) classified as STR-/FCI-. Of all discordant cases, 75 (6%) were STR+/FCI-, with only 5 (6.7%) cases best explained as identification of disease relapse. Eight cases were STR-/FCI+, representing relapsed/residual disease. Analysis of cases 1 year or more from transplant (54% of all cases) indicated only 9 (1.5%) were STR+/FCI-, and none uniquely identified relapse.

CONCLUSIONS

These data suggest that STR analysis performed 1 year or more post-HSCT does not identify unknown cases of relapse. Furthermore, while STR testing is critical for identifying graft failure/rejection within the first year posttransplant, FCI appears superior to STR at detecting late relapses with low-level disease. Therefore, STR testing from patients 1 year or more post-HSCT may be unnecessary, as BM biopsy evaluation is sufficient to identify disease relapse.

Incorporating patient-reported outcome data into a predictive calculator for allogeneic hematopoietic cell transplantation recipients

BACKGROUND

The Center for International Blood and Marrow Transplant Research (CIBMTR) provides a 1-year overall survival calculator to estimate outcomes for individual patients before they undergo allogeneic hematopoietic cell transplantation (HCT) to inform risk. The calculator considers pre-HCT clinical and demographic characteristics, but not patient-reported outcomes (PROs). Because pre-HCT PRO scores have been associated with post-HCT outcomes, the authors hypothesized that adding PRO scores to the calculator would enhance its predictive power.

METHODS

Clinical data were obtained from the CIBMTR and the Blood and Marrow Transplant Clinical Trials Network. The PRO measures used were the 36-Item Short Form Survey (SF-36) and the Functional Assessment of Cancer Therapy-Bone Marrow Transplantation. One thousand thirty-three adult patients were included.

RESULTS

When adjusted for clinical characteristics, the SF-36 physical component score was significantly predictive of 1-year survival (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.81-0.95; p = .0015), whereas the mental component score was not (HR, 1.02; 95% CI, 0.95-1.10; p = 0.6396). The baseline single general health question on the SF-36 was also significantly associated with mortality (HR, 1.91 for those reporting fair/poor health vs. good, very good, or excellent health; 95% CI, 1.33-2.76; p = .0005). The addition of PRO scores to the calculator did not result in a significant change in the model's predictive ability. Self-reported pre-HCT scores were strongly predictive of self-reported health status (odds ratio, 3.35; 95% CI, 1.66-6.75; p = .0007) and quality of life (odds ratio, 3.24; 95% CI, 1.93-5.41; p < .0001) after HCT.

CONCLUSIONS

The authors confirmed the significant, independent association of pre-HCT PRO scores with overall survival, although adding PRO scores to the survival calculator did not improve its performance. They also demonstrated that a single general health question was as accurate as the full measure for predicting survival, an important finding that may reduce respondent burden and promote its inclusion in routine clinical practice. Validation of these findings should be performed.

Efficacy of Autologous Hematopoietic Stem Cell Transplantation versus Chemotherapy or Allogeneic Hematopoietic Stem Cell Transplantation for Follicular Lymphoma: Systematic Review and Meta-Analysis

BACKGROUND

The effect of autologous hematopoietic stem cell transplantation (auto-HSCT) versus conventional chemotherapy or allogeneic hematopoietic stem cell transplantation (allo-HSCT) on the survival of patients with advanced follicular lymphoma (FL) is uncertain.

OBJECTIVES

To elucidate this, FL and HSCT were used as keywords to search in PubMed, Embase, Web of Science, and Cochrane Library databases.

METHOD

After data extraction and quality evaluation, a total of 13 studies were included, seven of which compared auto-HSCT with conventional chemotherapy and the other six compared allo-HSCT with auto-HSCT to the survival of FL patients.

RESULTS

The results showed that auto-HSCT improved overall survival (OS), progression-free survival, and event-free survival of FL patients compared with conventional chemotherapy without auto-HSCT. Compared with allo-HSCT, the patients receiving auto-HSCT had longer OS and lower non-recurrent mortality.

CONCLUSIONS

Auto-HSCT can provide a survival advantage for patients with FL compared with conventional chemotherapy and allo-HSCT did not result in a survival benefit.

Follicular lymphoma: 2023 update on diagnosis and management

DISEASE OVERVIEW

Follicular lymphoma (FL) is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. FL is characterized by diffuse lymphadenopathy, bone marrow involvement, and splenomegaly. Extranodal involvement is less common. Cytopenias are relatively common but constitutional symptoms of fever, night sweats, and weight loss are uncommon in the absence of transformation to diffuse large B cell lymphoma.

DIAGNOSIS

The diagnosis is based on histology from a biopsy of a lymph node or other affected tissue. Incisional biopsy is preferred over needle biopsies in order to give adequate tissue to assign grade and assess for transformation. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes.

RISK STRATIFICATION

The Follicular Lymphoma International Prognostic Index (FLIPI) uses five independent predictors of inferior survival: age >60 years, hemoglobin <12 g/dL, serum LDH > normal, Ann Arbor stage III/IV, number of involved nodal areas >4. The presence of 0-1, 2, and ≥3 adverse factors defines low, intermediate, and high-risk disease. There are other clinical prognostic models but the FLIPI remains the most common. Other factors such as time to relapse of less than 2 years from chemoimmunotherapy and specific gene mutations may also be useful for prognosis. Regardless of the prognostic model used, modern therapies have demonstrably improved prognosis.

RISK-ADAPTED THERAPY

Observation continues to be appropriate for asymptomatic patients with low bulk disease and no cytopenias. There is no overall survival (OS) advantage for early treatment with either chemotherapy or single-agent rituximab. For patients needing therapy, most patients are treated with chemoimmunotherapy, which has improved overall response rates (ORR), DOR, and OS. Randomized studies have shown additional benefits for maintenance of rituximab. Lenalidomide was non-inferior to chemoimmunotherapy in a randomized front-line study and, when combined with rituximab, was superior to rituximab alone in relapsed FL. Kinase inhibitors, stem cell transplantation (SCT), and chimeric antigen receptor T cells (CAR-T) are also considered for recurrent disease.

Nine-Year Follow-up of Patients with Relapsed Follicular Lymphoma after Nonmyeloablative Allogeneic Stem Cell Transplant and Autologous Transplant

PURPOSE

To compare outcomes between patients with relapsed follicular lymphoma who received a nonmyeloablative allogeneic stem cell transplant (alloSCT) and those who received an autologous transplant (autoSCT).

PATIENTS AND METHODS

We evaluated 194 patients with follicular lymphoma who received an alloSCT (n = 98) or autoSCT (n = 96) at MD Anderson Cancer Center (Houston, TX). The transplant type used was based on donor availability and by Medicare reimbursement guidelines. Patients who received an alloSCT were enrolled in four consecutive trials in which they received fludarabine, cyclophosphamide (or bendamustine), and rituximab conditioning. autoSCT patients received R-BEAM (rituximab, carmustine, etoposide, cytarabine, and melphalan).

RESULTS

The median follow-up of survivors was 108 months for the alloSCT group and 102 months for the autoSCT group. Overall survival was significantly better for patients who received an alloSCT compared with those who received an autoSCT (62% vs. 46%; P = 0.048). Similarly, progression-free survival rates were 52% in patients who received an alloSCT and 31% in those who received an autoSCT (P < 0.001), and the 8-year relapse rates were 11% and 43%, respectively (P < 0.0001). Only three patients in the alloSCT group relapsed beyond 3.5 years. In the alloSCT group, the rates for grade 2 to 4 acute graft-versus-host disease (GVHD), grade 3 to 4 acute GVHD, and extensive chronic GVHD were 22%, 9%, and 38%, respectively. In the autoSCT group, the 8-year incidence of secondary myelodysplasia was 11%. Nonrelapse mortality was similar between the two groups (15% vs. 11% at 8 years; P = 0.27).

CONCLUSIONS

This study shows that alloSCT is curative and confers superior survival compared with autoSCT in patients with follicular lymphoma.

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.

Cellular Therapy in Follicular Lymphoma: Autologous Stem Cell Transplantation, Allogeneic Stem Cell Transplantation, and Chimeric Antigen Receptor T-cell Therapy

A subset of follicular lymphoma patients with high-risk clinical features continues to pose a therapeutic challenge. Hematopoietic stem cell transplantation is a suitable consolidative treatment option for these patients. Data on chimeric antigen receptor T-cell therapy are promising in relapsed/refractory and transformed patients. The increasing armamentarium of nontransplant options coupled with the associated potential long-term sequelae of transplantation raises questions about the placement of transplant strategies in the follicular lymphoma treatment hierarchy.

A multi-center retrospective analysis of patients with relapsed/refractory follicular lymphoma after third-line chemotherapy

The overall outcome of patients with advanced-stage follicular lymphoma (FL) has improved significantly. However, some patients still develop multiple relapsed/refractory FL (RRFL). To address the still-limited data on this population, we performed this multi-center retrospective study. We analyzed 41 patients who received third-line treatment for RRFL at 8 institutes. The median age at diagnosis was 59 years (range, 38-70). The median progression-free survival (PFS) and probability of PFS at 2 years were 1.61 years and 39.4%, respectively, after third-line chemotherapy, and 0.45 years and 19.0%, respectively, after fourth-line chemotherapy. Objective response (OR) after third-line chemotherapy was achieved in 24 patients (53.7%). Bendamustine (Ben)-based regimens were associated with a significantly higher OR rate than other regimens (77.8% vs. 40.0%, respectively, P = 0.025). The median overall survival (OS) and probability of OS at 2 years were 4.71 years and 65.9%, respectively, after third-line chemotherapy, and 1.01 year and 45.1%, respectively, after fourth-line chemotherapy. In conclusion, this study had a small sample size and retrospective design, but it was able to demonstrate poor response rate and duration in patients with multiple RRFL, particularly after fourth-line chemotherapy. The optimal treatment strategy in this population should be clarified, including possibly hematopoietic stem cell transplantation.

Follicular lymphoma: 2020 update on diagnosis and management

DISEASE OVERVIEW

Follicular lymphoma (FL) is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. Follicular lymphoma is characterized by diffuse lymphadenopathy, bone marrow involvement, and splenomegaly. Extranodal involvement is less common. Cytopenias are relatively common but constitutional symptoms of fever, night sweats, and weight loss are uncommon in the absence of transformation to diffuse large B cell lymphoma.

DIAGNOSIS

The diagnosis is based on histology from a biopsy of a lymph node or other affected tissue. Incisional biopsy is preferred over needle biopsies in order to give adequate tissue to assign grade and assess for transformation. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10 and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes.

RISK STRATIFICATION

The Follicular Lymphoma International Prognostic Index (FLIPI) uses five independent predictors of inferior survival: age > 60 years, hemoglobin <12 g/dL, serum LDH > normal, Ann Arbor stage III/IV, number of involved nodal areas >4. The presence of 0-1, 2, and ≥ 3 adverse factors defines low, intermediate, and high-risk disease. There are other clinical prognostic models but the FLIPI remains the most common. Other factors such as time to relapse of less than 2 years from chemoimmunotherapy and specific gene mutations may also be useful for prognosis. Regardless of the prognostic model used, modern therapies have demonstrably improved prognosis.

RISK-ADAPTED THERAPY

Observation continues to be appropriate for asymptomatic patients with low bulk disease and no cytopenias. There is no overall survival advantage for early treatment with either chemotherapy or single agent rituximab. For patients needing therapy, most patients are treated with chemoimmunotherapy, which has improved response rates, duration of response and overall survival (OS). Randomized studies have shown additional benefit for maintenance rituximab. Lenalidomide was non-inferior to chemoimmunotherapy in a randomized front-line study and, when combined with rituximab, was superior to rituximab alone in relapsed FL. Kinase inhibitors, other immunotherapies, and stem cell transplantation (SCT) are also considered for recurrent disease.

Where does transplant fit in the age of targeted therapies?

The role of hematopoietic cell transplantation (HCT) for indolent lymphoma has evolved over the last 5 years with the availability of novel low-toxicity therapies and a better understanding of the prognosis of these entities. However, despite numerous treatment options for patients with follicular lymphoma, none are thought to be curative, and many require ongoing therapy with chronic toxicity. Historical trials indicate that autologous HCT as initial consolidation leads to improved progression-free survival, but not overall survival (OS) and, thus, is not typically recommended. However, autologous HCT for chemosensitive relapse can be carried out with ∼1% early mortality risk, affording disease control lasting a median of 3 to 5 years and the potential to improve OS. These results may compare favorably in efficacy, toxicity, and cost vs multiple sequential novel therapies with shorter durations of benefit. Recent data indicate that autologous HCT in follicular lymphoma patients with early initial progression will result in more than one third being alive and without relapse at 5 years, leading to improved OS when used within a year of the first recurrence. Unlike other available therapies, allogeneic HCT has the potential to cure up to one half of those transplanted with indolent B-cell non-Hodgkin lymphoma, although the risks need to be recognized and appropriate patient and donor selection is critical to ensure the best outcomes. HCT continues to remain a viable option in the current era of multiple targeted agents.

The Impact of First Complete Remission by PET-CT and Time to Next Treatment on Survival of Follicular Lymphoma Patients

We retrospectively analyzed the impact of initial positron emission tomography and computed tomography (PET-CT) complete remission (CR) and time to next treatment (TTNT) on patient outcome in follicular lymphoma. Between 2002 and 2014, 150 patients could be evaluated for treatment response and long-term outcome. The CR after first line treatment with either rituximab-cyclophosphamide, oncovin, and prednisolone (R-COP) or rituximab-cyclophosphamide, doxorubicin, oncovin, and prednisolone (R-CHOP) was 89% and partial response (PR) was 7%. The 5- and 10-year survival rates were 86.0% and 62.6%, respectively. In five years, 11% of patients had died of lymphoma and 3% from other causes. Forty-seven patients (31%) underwent a second line of treatment comprising 19 (40%) with a TTNT shorter than 24 months and 28 (60%) longer than 24 months. There was no difference in overall survival (OS) between R-COP (86%) and R-CHOP (77%) at 5 years, but there were more next treatment events in the R-COP compared with the R-CHOP group on longer follow-up (60% versus 35% at 8 years). For PET-CT response, there was a significant OS difference between initial CR and PR patients (88% versus 70%, p < 0.01), and a longer TTNT was seen in initial CR patients. Patients with a TTNT longer than 24 months had better OS compared with patients with a shorter TTNT (93% versus 54% at 5 years, p < 0.01). In conclusion, patients with initial PET-CT CR and TTNT longer than 24 months had better OS compared with those achieving only PR and shorter TTNT. PET-CT CR should be considered the treatment goal during initial treatment, and more aggressive treatment should be considered for patients with a TTNT of less than 24 months.

Advances in Transplantation for Lymphomas Resulting from CIBMTR Lymphoma Working Committee's Research Portfolio: A Five-Year Report (2013-2018)

The Center for International Blood and Marrow Transplant Research (CIBMTR) is a research collaboration between the National Marrow Donor Program (NMDP)/Be The Match and the Medical College of Wisconsin (MCW). The CIBMTR collaborates with the global scientific community to advance hematopoietic cell transplantation (HCT) and cellular therapy worldwide to increase survival and enrich quality of life for patients. The observation research program within CIBMTR is organized into 15 working committees. This review is aiming to highlight the observational research studies published by the CIBMTR Lymphoma Working committee over the last five years (2013-18) and to summarize how these studies have impacted the field by helping inform clinical practice in scenarios where prospective data from high quality randomized trials were not available or where owing to the rarity of a particular transplant indication such data were unlikely to be generated, outside the setting of a large observational research database. The salient findings reviewed include; (a) studies supporting role of autologous HCT in diffuse large B-cell lymphoma (DLBCL) patients with sensitive relapse of disease within one year of diagnosis, (b) role of autologous HCT vs allogeneic HCT in follicular lymphoma patients with early therapy failure, (c) prognostic scoring system development for classical Hodgkin lymphoma and DLBCL patients with prior autograft failure, (d) defining the role of alternative donor transplantation in lymphomas, (e) evaluating appropriate conditioning regimens for HCT in lymphoma, and (f) outcomes of HCT in rare lymphoid malignancies.

Follicular lymphoma: 2018 update on diagnosis and management

DISEASE OVERVIEW

Follicular lymphoma is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. Follicular lymphoma (FL) is characterized by diffuse lymphadenopathy, bone marrow involvement, splenomegaly and less commonly other extranodal sites of involvement. In general, cytopenias can occur but constitutional symptoms of fever, nightsweats, and weight loss are uncommon.

DIAGNOSIS

Diagnosis is based on histology of preferably a biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes.

RISK STRATIFICATION

The Follicular Lymphoma International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age >60 years, hemoglobin <12 g/dL, serum LDH > normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0, 1, 2, and ≥ 3 adverse factors defines low, intermediate, and high-risk disease. With the use of more modern therapies, outcomes have improved.

RISK-ADAPTED THERAPY

Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias, with no survival advantage for early treatment with either chemotherapy or rituximab alone. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single agent rituximab. Experimental therapies as well as stem cell transplantation (SCT) are considered for recurrent disease.

Allogeneic Transplantation for Follicular Lymphoma: Does One Size Fit All?

Follicular lymphoma (FL) exhibits striking biologic and clinical heterogeneity. Patients with newly diagnosed asymptomatic or low-bulk disease may be observed or managed with immunotherapies alone. Chemoimmunotherapy is considered a standard treatment for patients with advanced, symptomatic disease. In patients with FL who achieve at least a partial remission after first-line chemoimmunotherapy, autologous (auto-) hematopoietic cell transplantation (HCT) consolidation is not recommended; however, most patients with FL experience disease relapse after frontline therapies, with the experience of therapy failure within 2 years of first-line treatments predicting poor survival. Despite remarkable efficacy, even in patients who experience failure with other therapies, auto-HCT and allogeneic (allo-) HCT remain underutilized in relapsed/refractory FL, even among healthy and younger patients. Early use of auto-HCT consolidation should be considered a standard therapy option for high-risk patients who experience early failure of chemoimmunotherapy (< 2 years). For patients with FL who experience failure of frontline therapies late (> 2 years), deferring auto-HCT until later in the disease course is reasonable. Allo-HCT is best reserved for medically fit individuals with heavily pretreated disease, persistent marrow involvement, refractory, but low-bulk, disease, and in those who experience a failure to mobilize stem cells for auto-HCT. Allo-HCT is also a reasonable option for patients with FL who experience failure with a prior autograft; lower-intensity conditioning regimens and HLA-matched related donors are preferred in that setting. Future research should focus on the eradication of minimal residual disease before HCT and the prevention of disease relapse after HCT by integrating novel targeted agents into pre-HCT and post-HCT regimens.

[Allogeneic haematopoietic cell transplantation for indolent lymphomas: Guidelines from the Francophone Society Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

Despite great improvements in the outcome of patients with lymphoma, some may still relapse or present with primary refractory disease. In these situations, allogeneic hematopoietic cell transplantation is a potentially curative option, this is true particularly the case of relapse after autologous stem cell transplantation. Recently, novel agents such as anti-PD1 and BTK inhibitors have started to challenge the use of allogeneic hematopoietic cell transplantation for relapsed or refractory lymphoma. During the 2016 annual workshop of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC), we performed a comprehensive review of the literature published in the last 10 years and established guidelines to clarify the indications and transplant modalities in this setting. This paper specifically reports on our conclusions regarding indolent lymphomas, mainly follicular lymphoma and chronic lymphocytic leukemia.

The role of stem cell transplantation in follicular lymphoma

With the introduction of novel treatments paradigms to if or when to use transplantation strategies for patients with follicular lymphoma have changed substantially. Autologous transplantation has been intensively evaluated as consolidation after first induction treatment with positive effects, however the introduction of Rituximab led to comparable improvements and HDT has been moved to relapse treatment. In this indication HDT was frequently use already at first relapse, but now is dominantly used in patients with a highrisk profile, e.g. failure of response, early or multiply relapse and/or signs of transformation. The ideal place for allogeneic transplantation is even harder to define, as the curative potential might be outweighed by the substantial side effect profile and the indication must always be discussed in the light of available alternatives. In consequence, transplantation strategies remain an important therapeutic instrument for patients with FL, however timing within the treatment course has to be defined individually.

Hematopoietic cell transplantation for diffuse large B-cell and follicular lymphoma: Current controversies and advances

Non-Hodgkin's lymphoma (NHL) constitutes a collection of lymphoproliferative disorders with diverse biologic, histologic, and clinical features. With a better understanding of the molecular pathogenesis, recently there have been major advances in the treatment of NHLs including addition of novel monoclonal antibodies, targeted therapies, and immune activators to the therapy armamentarium. Despite these remarkable developments, autologous hematopoietic cell transplantation (auto-HCT) remains not only a standard-of-care curative option for aggressive NHL but also an important therapeutic option for indolent NHL. In NHL, for patients with high-risk features, including those heavily pretreated or with refractory disease or those experiencing failure after an auto-HCT, allogeneic HCT (allo-HCT) remains the only curative option. In this review, we briefly discuss the role of transplantation in diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL). In DLBCL patients, we discuss the role of HCT in clinically and biologically defined ultra-high-risk disease. In FL patients, auto-HCT is best reserved for relapsed chemosensitive patients after two to three lines of prior chemoimmunotherapies, who are not candidates for allo-HCT, either because of donor unavailability, associated comorbidities, or patient preference. Reduced-intensity conditioning allo-HCT offers the curative option for patients with relapsed/refractory FL. Although the emergence of targeted, biologic, and immunological therapies is welcoming, it is currently unclear how these new therapies might enhance or replace allo-HCT. Until we have further definitive data, allo-HCT remains the only curative option.

The role of stem-cell transplantation in the treatment of marginal zone lymphoma

High-dose chemotherapy and autologous stem-cell transplantation (ASCT) is standard therapy in relapsed/refractory aggressive lymphoma. The optimal therapy of relapsed/refractory disseminated marginal-zone lymphoma (MZL) has not been defined. Limited data on ASCT in this setting suggests outcomes are similar to what is expected in follicular lymphoma. International guidelines suggest that ASCT should be considered in follicular lymphoma in second or subsequent remission, in particular in high-risk disease, or following disease transformation. These guidelines can be extrapolated to MZL. ASCT is not considered curative but a subset of patients achieve very long remissions. The major concern is the occurrence of secondary malignancies possibly related to total-body irradiation. Allogeneic SCT is usually considered after failure of ASCT, but can also be considered upfront in younger patients seeking curative approach. The introduction of novel/targeted therapies may change the role and timing SCT may have in the treatment algorithm of indolent lymphomas.

Long-term outcomes of high dose treatment and autologous stem cell transplantation in follicular and mantle cell lymphomas - a single centre experience

BACKGROUND

Advanced follicular lymphoma (FL) and mantle cell lymphoma (MCL) are incurable diseases with conventional treatment. The high dose treatment (HDT) with autologous stem cell transplantation (ASCT), however, offers a certain proportion of these patients the prospect of a prolonged disease-free and overall survival. The aim of this study was to investigate the event free survival (EFS) and overall survival (OS) in patients with FL and MCL treated with ASCT.

PATIENTS AND METHODS

Seventeen patients with FL and 29 patients with MCL were included, 15 of them were transplanted to consolidate the response to second line treatment and 24 to consolidate their first remission, respectively. All were conditioned with total body irradiation (TBI) and high dose cyclophosphamide between 2006 and 2014 and all were transplanted with peripheral blood stem cells.

RESULTS

The estimated 5-year OS for FL was 87.8% (95% confidence interval [CI] 59.5%-96.8%) and for MCL 79.3% (95% CI 56.1%-91.1%), respectively. The estimated 5-year EFS for FL was 76.0% (95% CI 48.0%-90.3%) and for MCL 69.8% (95% CI 45.5%-84.8%), respectively. There were no secondary hematological malignancies observed in either group.

CONCLUSIONS

Based on above results, the ASCT with TBI is a good treatment option in terms of long-term survival for patients with follicular and mantle cell lymphoma demonstrating a relatively low rate of late toxicities and secondary malignancies.

Outcome Comparison of Allogeneic versus Autologous Stem Cell Transplantation in Transformed Low-Grade Lymphoid Malignancies: A Systematic Review and Pooled Analysis of Comparative Studies

BACKGROUND

Some patients with low-grade lymphoid malignancies develop transformed disease, requiring stem cell transplantation (SCT). SCT outcomes in transformed low-grade lymphoid malignancies may differ from those of nontransformed disease or other aggressive non-Hodgkin lymphomas. We conducted a pooled analysis of the clinical outcomes of allogeneic versus high-dose therapy (HDT) with autologous SCT in adult patients with transformed low-grade lymphoid malignancies.

METHODS

A PubMed, EMBASE, and Cochrane search yielded 4 comparative studies reporting allogeneic versus HDT with autologous SCT outcomes in adults (age ≥18) with transformed low-grade lymphoid malignancies, including follicular, chronic/small lymphocytic, and marginal zone lymphoma. Risk ratio (RR) and 95% CI were calculated using random-effects models.

RESULTS

Rates for overall survival (OS) were 51.0 versus 69.5% (RR = 1.55, 95% CI 1.19-2.02, p = 0.001), rates of relapse were 37.3 versus 35.3% (RR = 1.04, 95% CI 0.70-1.55, p = 0.84), and rates of transplant-related mortality (TRM) were 33.3 versus 7.2% (RR = 4.52, 95% CI 2.75-7.43, p < 0.00001) for allogeneic versus autologous SCT. Previous rituximab treatment, reduced intensity conditioning regimen prior to SCT, or original pathology had no prognostic impact.

CONCLUSION

HDT followed by autologous SCT was associated with lower TRM and a better OS, but there was no difference in relapse versus allogeneic SCT. Autologous SCT may be the better therapeutic option, considering the second chance of allogeneic SCT in the case of relapse.

The Blood and Marrow Transplant Clinical Trials Network: An Effective Infrastructure for Addressing Important Issues in Hematopoietic Cell Transplantation

Hematopoietic cell transplantation (HCT) is a rapidly evolving field with active preclinical and clinical development of new strategies for patient assessment, graft selection and manipulation, and pre- and post-transplantation drug and cell therapy. New strategies require evaluation in definitive clinical trials; however, HCT trials face unique challenges, including the relatively small number of transplantations performed at any single center, the diverse indications for HCT requiring dissimilar approaches, the complex nature of the intervention itself, the risk of multiple complications in the immediate post-transplantation period, and the risk of important, though infrequent, late effects. The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) was established by the US National Heart Lung and Blood Institute and the National Cancer Institute to meet these challenges. In its 15 years as a network, the BMT CTN has proven to be a successful infrastructure for planning, implementing, and completing such trials and for providing definitive answers to questions leading to improvements in the understanding and practice of HCT. It has opened 37 trials, about one-half phase 2 and one-half phase 3, enrolled more than 8000 patients, and published 57 papers addressing important issues in the treatment of patients with life-threatening malignant and nonmalignant blood disorders. This review describes the network's accomplishments, key components of its success, lessons learned over the past 15 years, and challenges for the future.

Reappraising the timing of transplant for indolent non-Hodgkin lymphomas

INTRODUCTION

Indolent non-Hodgkin lymphomas (iNHL) remain incurable with standard approaches. The timing of autologous stem cell transplant (ASCT) is changing following the introduction of new drugs that can potentially defer the transplant, improved reduced intensity conditioning (RIC) and haploidentical allogeneic SCT (allo-SCT).

AREAS COVERED

The most relevant aspects concerning the role of hematopoietic stem cell transplantation in the management of iNHL are discussed. Literature search methodology included examination of PubMed index and meeting presentations. Expert commentary: ASCT is not currently employed as consolidation in first-line, being reserved to patients with refractory/relapsed disease. The curative potential of graft-versus-lymphoma (GVL) after RIC allo-SCT could be particularly beneficial in patients with iNHL relapsing after ASCT. This scenario could be modified in the near future by better definition of high-risk patients at diagnosis, by the improvement of minimal residual disease (MRD) evaluation and by the introduction of new drugs in the therapeutic algorithm.

The role of autologous and allogeneic stem cell transplantation in the management of indolent B-cell lymphoma

Despite improvements over the past decade in the overall survival of patients with indolent non-Hodgkin lymphomas, these lymphomas remain largely incurable with standard therapies. Immunochemotherapy with rituximab-based regimens has become a well-established standard of care in the primary and relapsed disease settings. The role of hematopoietic stem cell transplantation in indolent lymphoma has been defined by the adoption of this therapy largely in the relapse setting because randomized trials in the first-line setting have not shown survival advantages. Allogeneic stem cell transplantation has the possibility for cure because of the potential for immunologic graft-versus-lymphoma effect, but there are significant concerns regarding nonrelapse mortality. Autologous stem cell transplantation offers a safe treatment platform, but relapse remains a significant issue. The role of transplantation in the current treatment landscape of immunochemotherapy has not been conclusively proven, and randomized trials are lacking. This review summarizes the current relevant data regarding transplantation in indolent non-Hodgkin lymphoma and highlights the issues relevant to clinicians in the field.

Allogeneic Hematopoietic Cell Transplantation as Curative Therapy for Patients with Non-Hodgkin Lymphoma: Increasingly Successful Application to Older Patients

Non-Hodgkin lymphoma (NHL) constitutes a collection of lymphoproliferative disorders with widely varying biological, histological, and clinical features. For the B cell NHLs, great progress has been made due to the addition of monoclonal antibodies and, more recently, other novel agents including B cell receptor signaling inhibitors, immunomodulatory agents, and proteasome inhibitors. Autologous hematopoietic cell transplantation (auto-HCT) offers the promise of cure or prolonged remission in some NHL patients. For some patients, however, auto-HCT may never be a viable option, whereas in others, the disease may progress despite auto-HCT. In those settings, allogeneic HCT (allo-HCT) offers the potential for cure. Over the past 10 to 15 years, considerable progress has been made in the implementation of allo-HCT, such that this approach now is a highly effective therapy for patients up to (and even beyond) age 75 years. Recent advances in conventional lymphoma therapy, peritransplantation supportive care, patient selection, and donor selection (including the use of alternative hematopoietic cell donors), has allowed broader application of allo-HCT to patients with NHL. As a result, an ever-increasing number of NHL patients over age 60 to 65 years stand to benefit from allo-HCT. In this review, we present data in support of the use of allo-HCT for patients with diffuse large B cell lymphoma, follicular lymphoma, and mantle cell lymphoma. These histologies account for a large majority of allo-HCTs performed for patients over age 60 in the United States. Where possible, we highlight available data in older patients. This body of literature strongly supports the concept that allo-HCT should be offered to fit patients well beyond age 65 and, accordingly, that this treatment should be covered by their insurance carriers.

Reduced-Intensity Conditioning with Fludarabine, Cyclophosphamide, and High-Dose Rituximab for Allogeneic Hematopoietic Cell Transplantation for Follicular Lymphoma: A Phase Two Multicenter Trial from the Blood and Marrow Transplant Clinical Trials Network

Allogeneic (allo) hematopoietic cell transplantation (HCT) can induce long-term remissions in chemosensitive relapsed follicular lymphoma (FL). The Blood and Marrow Transplant Clinical Trials Network conducted a multicenter phase 2 trial to examine the efficacy of alloHCT using reduced-intensity conditioning with rituximab (RTX) in multiply relapsed, chemosensitive FL. The primary endpoint was 2-year progression-free survival (PFS). The conditioning regimen consisted of fludarabine, cyclophosphamide, and high-dose RTX (FCR), in which 3 of the 4 doses of RTX were administered at a dose of 1 gm/m(2). Graft-versus-host disease (GVHD) prophylaxis was with tacrolimus and methotrexate. Sixty-five patients were enrolled and 62 were evaluable. Median age was 55 years (range, 29 to 74). This group was heavily pretreated: 77% had received ≥ 3 prior regimens, 32% had received ≥ 5 prior regimens, and 11% had received prior autologous HCT. Donors were HLA-matched siblings (n = 33) or HLA-matched unrelated adults (n = 29). No graft failures occurred. The overall response rate after HCT was 94% with 90% in complete remission (CR), including 24 patients not in CR before alloHCT. With a median follow-up of 47 months (range, 30 to 73), 3-year PFS and overall survival rates were 71% (95% confidence interval, 58% to 81%) and 82% (95% confidence interval, 70% to 90%), respectively. Three-year cumulative incidences of relapse/progression and nonrelapse mortality were 13% and 16%, respectively. Two-year cumulative incidences of grades 2 to 4 and grades 3 or 4 acute GVHD were 27% and 10%, respectively, and extensive chronic GVHD incidence was 55%. Serum RTX concentrations peaked at day +28 and remained detectable as late as 1 year in 59% of patients with available data. In conclusion, alloHCT with FCR conditioning confers high CR rates, a low incidence of relapse/progression, and excellent survival probabilities in heavily pretreated FL patients.

The potential benefit of allogeneic over autologous transplantation in patients with very early relapsed and refractory follicular lymphoma with prior remission duration of ≤12 months

Early relapsed or refractory follicular lymphoma (FL) warrants consolidation with transplantation, though graft source modality remains controversial. We analysed the outcomes of 44 patients transplanted with either autologous or allogeneic graft sources in the post-rituximab era. No difference in event-free (EFS) or overall survival (OS) was observed between allogeneic (81% and 81%) and autologous transplantation (64% and 70%) at 3 years. There was a significant difference in EFS between allogeneic and autologous transplantation patients with previous remission duration of ≤12 months (80% and 42% at 3 years, P < 0·015). Very early relapsed FL may warrant consideration of allogeneic over autologous transplantation in the appropriate setting.

Follicular lymphoma: 2015 update on diagnosis and management

DISEASE OVERVIEW

Follicular lymphoma is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. Follicular lymphoma (FL) is characterized by diffuse lymphoadenopathy, bone marrow involvement, splenomegaly, and less commonly other extranodal sites of involvement. In general, cytopenias can occur but constitutional symptoms of fever, night sweats, and weight loss are uncommon.

DIAGNOSIS

Diagnosis is based on histology of preferably a biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes.

RISK STRATIFICATION

The Follicular Lymphoma International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age >60 years, hemoglobin <12 g/dL, serum LDH > normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0, 1, 2, and ≥ 3 adverse factors defines low, intermediate, and high-risk disease. With the use of more modern therapies, outcomes have improved.

RISK-ADAPTED THERAPY

Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias, with no survival advantage for early treatment with either chemotherapy or rituximab alone. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single agent rituximab. Experimental therapies as well as stem cell transplantation (SCT) are considered for recurrent disease.

Reduced-Intensity Allografting as First Transplantation Approach in Relapsed/Refractory Grades One and Two Follicular Lymphoma Provides Improved Outcomes in Long-Term Survivors

This study was conducted to compare long-term outcomes in patients with refractory/relapsed grades 1 and 2 follicular lymphoma (FL) after allogeneic (allo) versus autologous (auto) hematopoietic cell transplantation (HCT) in the rituximab era. Adult patients with relapsed/refractory grades 1 and 2 FL undergoing first reduced-intensity allo-HCT or first autograft during 2000 to 2012 were evaluated. A total of 518 rituximab-treated patients were included. Allo-HCT patients were younger and more heavily pretreated, and more patients had advanced stage and chemoresistant disease. The 5-year adjusted probabilities, comparing auto-HCT versus allo-HCT groups for nonrelapse mortality (NRM) were 5% versus 26% (P < .0001); relapse/progression: 54% versus 20% (P < .0001); progression-free survival (PFS): 41% versus 58% (P < .001), and overall survival (OS): 74% versus 66% (P = .05). Auto-HCT was associated with a higher risk of relapse/progression beyond 5 months after HCT (relative risk [RR], 4.4; P < .0001) and worse PFS (RR, 2.9; P < .0001) beyond 11 months after HCT. In the first 24 months after HCT, auto-HCT was associated with improved OS (RR, .41; P < .0001), but beyond 24 months, it was associated with inferior OS (RR, 2.2; P = .006). A landmark analysis of patients alive and progression-free at 2 years after HCT confirmed these observations, showing no difference in further NRM between both groups, but there was significantly higher risk of relapse/progression (RR, 7.3; P < .0001) and inferior PFS (RR, 3.2; P < .0001) and OS (RR, 2.1; P = .04) after auto-HCT. The 10-year cumulative incidences of second hematological malignancies after allo-HCT and auto-HCT were 0% and 7%, respectively. Auto-HCT and reduced-intensity-conditioned allo-HCT as first transplantation approach can provide durable disease control in grades 1 and 2 FL patients. Continued disease relapse risk after auto-HCT translates into improved PFS and OS after allo-HCT in long-term survivors.

Indications for allo- and auto-SCT for haematological diseases, solid tumours and immune disorders: current practice in Europe, 2015

This is the sixth special report that the European Society for Blood and Marrow Transplantation regularly publishes on the current practice and indications for haematopoietic SCT for haematological diseases, solid tumours and immune disorders in Europe. Major changes have occurred in the field of haematopoietic SCT over the last years. Cord blood units as well as haploidentical donors have been increasingly used as stem cell sources for allo-SCT, thus, augmenting the possibility of finding a suitable donor for a patient. Continuous refinement of conditioning strategies has also expanded not only the number of potential indications but also has permitted consideration of older patients or those with co-morbidity for a transplant. There is accumulating evidence of the role of haematopoietic SCT in non-haematological disorders such as autoimmune diseases. On the other hand, the advent of new drugs and very effective targeted therapy has challenged the role of SCT in some instances or at least, modified its position in the treatment armamentarium of a given patient. An updated report with revised tables and operating definitions is presented.

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.

Autologous stem cell transplantation for follicular lymphoma is of most benefit early in the disease course and can result in durable remissions, irrespective of prior rituximab exposure

The role of autologous stem cell transplantation (ASCT) and the optimal timing of such transplants in patients with follicular lymphoma (FL) remains contentious. We present a single-centre experience documenting the outcomes of 70 FL patients who underwent BEAM (carmustine, cytarabine, etopside, melphalan)-conditioned ASCT between 1988 and 2009. With a median follow-up of 6·8 years (0·1-19·2), the 7-year overall survival (OS) and progression-free survival (PFS) from the date of ASCT was 76% and 60%, respectively. A significant difference in OS was found when comparing the patients transplanted in first or second remission versus those transplanted in later remissions (P = 0·02) and this significance was maintained when OS was calculated from the date of diagnosis (P = 0·03). There was a plateau on the PFS curves for patients transplanted in either first or second remissions after 9·3 and 6·4 years respectively, suggesting that these groups may never relapse. No differences were seen in OS or PFS in those treated with rituximab prior to transplant versus those who were not. Our data shows that BEAM ASCT can be a highly effective treatment in patients with FL early in the disease course, and that a proportion of patients experience prolonged disease-free survival and may be cured.

Follicular lymphoma: 2014 update on diagnosis and management

DISEASE OVERVIEW

Follicular lymphoma is generally an indolent B cell lymphoproliferative disorder of transformed follicular center B cells. Follicular lymphoma (FL) is characterized by diffuse lymphoadenopathy, bone marrow involvement, splenomegaly, and less commonly other extranodal sites of involvement. In general cytopenias can occur but constitutional symptoms of fever, nightsweats, and weight loss are uncommon.

DIAGNOSIS

Diagnosis is based on histology of preferably a biopsy of a lymph node. Immunohistochemical staining is positive in virtually all cases for cell surface CD19, CD20, CD10, and monoclonal immunoglobulin, as well as cytoplasmic expression of bcl-2 protein. The overwhelming majority of cases have the characteristic t(14;18) translocation involving the IgH/bcl-2 genes.

RISK STRATIFICATION

The Follicular Lymphoma International Prognostic Index prognostic model for FL uses five independent predictors of inferior survival: age >60 years, hemoglobin <12 g/dL, serum LDH > normal, Ann Arbor stage III/IV, number of involved nodal areas > 4. The presence of 0, 1, 2, and  ≥ 3 adverse factors defines low, intermediate, and high-risk disease. With the use of more modern therapies, outcomes have improved.

RISK-ADAPTED THERAPY

Observation continues to be adequate for asymptomatic patients with low bulk disease and no cytopenias. For patients needing therapy, most patients are treated with chemotherapy plus rituximab, which has improved response rates, duration of response and overall survival. Randomized studies have shown additional benefit for maintenance rituximab both following chemotherapy-rituximab and single agent rituximab. Experimental therapies as well as stem cell transplantation (SCT) are considered for recurrent disease.

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.

Clinical outcomes of allogeneic stem cell transplantation for relapsed or refractory follicular lymphoma: a retrospective analysis by the Fukuoka Blood and Marrow Transplantation Group

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is considered the only curative treatment for relapsed or refractory follicular lymphoma (FL), but it has a high treatment-related mortality rate. Only a few reports, however, have described the efficacy of allo-SCT for FL in the Japanese population. We retrospectively analyzed the outcome of allo-SCT in 30 patients with FL. Seventeen (56.7 %) patients were chemorefractory, whereas 13 (43.3 %) were chemosensitive. An estimated 2-year overall survival rate (OS) and relapse rate of all patients was 46.7 and 20.0 %, respectively. There were no significant differences in the estimated 2-year OS rate between patients who received myeloablative conditioning and those who received reduced-intensity conditioning (P = 0.98), and among the recipients of related bone marrow (BM)/peripheral blood stem cell, unrelated BM and umbilical cord blood (P = 0.20). In patients who were either chemosensitive or chemorefractory at allo-SCT, the 2-year OS rate was 69.2 and 29.4 % (P = 0.06). Patients with mild-to-moderate acute GVHD had better 2-year PFS rate compared with patients who had severe acute GVHD (P = 0.01), but not better PFS compared with patients who had no acute GVHD (P = 0.12). Our results suggest that the graft-versus-lymphoma effects of allo-SCT may provide survival benefits even in patients with chemorefractory FL.

Nonmyeloablative allogeneic stem cell transplantation for non-hodgkin lymphoma

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