Outcome of Allogeneic Transplantation for Mature T-cell Lymphomas: Impact of Donor Source and Disease Characteristics

Comparative outcomes of various transplantation platforms, highlighting haploidentical transplants with post-transplantation cyclophosphamide for adult T-cell leukaemia/lymphoma

This study retrospectively compared outcomes of various allogeneic haematopoietic cell transplantation (allo-HCT) platforms in patients with adult T-cell leukaemia/lymphoma. Platforms included human leukocyte antigen (HLA)-haploidentical-related donors using post-transplant cyclophosphamide (PTCY), HLA-matched related donors (MRD), HLA-matched unrelated donors (MUD) and cord blood transplantation (CBT). Patients who underwent their first allo-HCT between 2016 and 2021 were included. Outcomes analysed were overall survival (OS), relapse and non-relapse mortality (NRM). Seven hundred patients were included (PTCY, n = 121; MRD, n = 91; MUD, n = 160; CBT, n = 328). With a median follow-up of 794 days for survivors, 2-year OS was 48.1% (PTCY), 48.8% (MRD), 48.4% (MUD) and 34.6% (CBT); the respective 2-year cumulative incidence of relapse was 37.1%, 47.5%, 33.9% and 45.1% and that of NRM was 24.2%, 19.8%, 24.7% and 27.3%. PTCY was associated with delayed platelet engraftment relative to MRD and MUD. There was no increase in the incidence of severe acute or chronic graft-versus-host disease. In the PTCY group, poor performance status was a significant predictor of inferior OS, and infused CD34+ cell numbers of less than 5 × 106/kg were associated with delayed neutrophil and platelet engraftment. These results suggest that allo-HCT with PTCY is a safe and effective platform for patients with adult T-cell leukaemia/lymphoma.

Allogeneic stem cell transplantation against aggressive lymphomas: graft-versus-lymphoma effects in peripheral T-cell lymphoma and diffuse large B-cell lymphoma after myeloablative conditioning

Allogeneic stem cell transplantation (alloSCT) represents a curative option for patients with relapsed/refractory (r/r) aggressive lymphomas. We compared outcomes of alloSCT in r/r PTCL and r/r DLBCL pts (n = 150) who underwent identical myeloablative conditioning chemotherapy, GvHD prophylaxis, and relapse management. 5-year PFS and OS were significantly superior in PTCL compared to DLBCL (56% vs. 24%; 56% vs. 28%; p ≤ 0.005). A landmark analysis (day≥ +100 post-alloSCT) markedly favored outcomes in PTCL vs. DLBCL: 5-year PFS and OS of 76% vs. 30% and 76% and 35%, respectively (p ≤ 0.003). Non-relapse mortality was comparable (35% PTCL vs. 34% DLBCL, p = 0.894), whereas post-alloSCT relapse mortality was significantly higher in DLBCL (36% vs. 10%, p = 0.0007). The occurence of limited chronic GvHD did not improve outcomes in DLBCL, whereas extensive chronic GvHD was a negative risk factor for both (HR 2.09 and 2.80, p ≤ 0.006). In conclusion, we gained evidence for strong graft-versus-lymphoma activity against PTCL but not DLBCL.

DL-ICE as a bridge to allogeneic transplantation in relapsed/refractory PTCL: survival outcomes and prognostic factors

Introduction

Peripheral T-cell lymphomas (PTCLs) have poor outcomes in the relapsed/refractory (R/R) setting. In this study, we evaluated the efficacy of dexamethasone, L-asparaginase, ifosfamide, carboplatin, and etoposide (DL-ICE) chemotherapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with R/R PTCLs.

Methods

We retrospectively analyzed 80 adult patients with R/R PTCLs treated with DL-ICE chemotherapy between September 2009 and March 2023. Patients achieving complete or partial remission were eligible for consolidative allo-HSCT. Overall survival (OS) and progression-free survival (PFS) were evaluated.

Results

The overall response rate to DL-ICE was 37.5%, with 30% achieving complete remission (CR). With a median follow-up of 96.4 months, the median OS and PFS were 8.9 and 3.8 months, respectively. Seventeen patients (21%) underwent allo-HSCT, including 11 with non-CR status. The 5-year OS was significantly higher in the allo-HSCT group compared to that in the group with chemotherapy alone (64.7% vs 18.3%, p <0.001). Multivariate analysis identified advanced stage, EBV viremia, and non-CR status as poor prognostic factors.

Discussion

DL-ICE chemotherapy demonstrated modest activity in R/R PTCLs. Consolidation with allo-HSCT, even in patients who do not achieve CR, resulted in long-term survival in a subset of patients. Early consideration of allo-HSCT may improve outcomes for patients with R/R PTCLs.

The role of stem cell transplant (auto and allo) in PTCL and CTCL

In contrast to B-cell lymphoma, the advent of modern targeting drugs and immunotherapeutics has not led to major breakthroughs in the treatment of peripheral T-cell lymphoma (PTCL) to date. Therefore, both autologous and allogeneic hematopoietic cell transplantation (HCT) continue to play a central role in the management of PTCL. Focusing on the most common entities (PTCL not otherwise specified, angioimmunoblastic T-cell lymphoma, and ALK-negative anaplastic large cell lymphoma), we summarize evidence, indications, and points to consider for transplant strategies in PTCL by treatment line. Although cutaneous T-cell lymphomas (CTCLs) are biologically and clinically distinct from the aforementioned PTCL, both disease groups appear to be susceptible to the graft-versus-lymphoma effects conferred by allogeneic HCT (alloHCT), setting the stage for alloHCT as a potentially curative treatment in otherwise incurable CTCL, such as mycosis fungoides/Sezary syndrome. Nevertheless, specific aspects regarding indication and prerequisites for alloHCT in CTCL need to be considered. Given the inherent toxicity of alloHCT and the significant risk of relapse after transplant, only intelligent strategies embedding alloHCT in current PTCL/CTCL treatment algorithms in terms of patient selection, timing, pretransplant preparation, and posttransplant maintenance provide optimal results. New targeted and cellular therapies, either complementary or competitive to HCT, are eagerly awaited in order to improve PTCL/CTCL outcomes.

Maintenance Therapy Post-Stem Cell Transplantation for Patients with T-Cell Lymphomas

PURPOSE OF REVIEW

Given the poor outcomes for peripheral T-cell lymphomas (PTCL), stem cell transplant (SCT) remains an important therapeutic approach. Post-SCT relapse is common and maintenance therapy post-SCT is increasingly being utilized. Here we review the use of post-SCT maintenance therapy for PTCL patients.

RECENT FINDINGS

Maintenance therapy is increasingly utilized to decrease post-SCT relapse and improve outcomes in PTCL. Ongoing and completed post-SCT maintenance trials utilizing agents such as romidepsin, brentuximab vedotin, duvelisib, and pembrolizumab have shown efficacy in decreasing relapse. Further, additional agents with efficacy in PTCL have emerged that may inform future maintenance approaches. Maintenance therapy is a promising approach to maintain response after SCT in PTCL. While several trials are ongoing to evaluate maintenance therapy in PTCL, current data suggests this may be an effective method to decrease post-SCT relapse.

Long-Term Follow-Up of the Prospective Randomized AATT Study (Autologous or Allogeneic Transplantation in Patients With Peripheral T-Cell Lymphoma)

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.Primary analysis of the phase III randomized AATT study showed that younger patients with peripheral T-cell lymphoma (PTCL) consolidated with autologous or allogeneic transplantation (alloSCT) had similar event-free survival (EFS) and overall survival (OS). Seven-year EFS of patients randomly assigned to alloSCT was 38% (95% CI, 25 to 52) compared with 34% (95% CI, 22 to 47) for patients randomly assigned to autologous transplantation of hematopoietic stem cells (autoSCT); OS was 55% (95% CI, 41 to 69) and 61% (95% CI, 47 to 74). Among patients undergoing alloSCT (n = 26) or autoSCT (n = 41) on study, the cumulative progression/relapse rate was 8% (95% CI, 0 to 19) and 55% (95% CI, 35 to 74). Nonrelapse mortality (NRM) was 31% (95% CI, 13 to 49) and 3% (95% CI, 0 to 8) after alloSCT and autoSCT, respectively. Fifteen of 30 patients with early progression and 11 of 20 patients with progression/relapse after autoSCT received alloSCT. Seven-year OS after salvage alloSCT was 61% (95% CI, 47 to 74); NRM was 23% (95% CI, 6 to 40). Long-term follow-up documents the strong graft versus lymphoma effect of alloSCT independent of the timing of transplantation. Survival of patients unable to undergo transplantation was dismal. AlloSCT is the treatment of choice for younger, transplant-eligible patients with relapsed/refractory PTCL. AlloSCT is currently not recommended as part of first-line consolidation.

Hematological Oncology journal women in lymphoma special issue: Latest updates in nodal peripheral T-cell lymphoma

In the last decade, there has been increased understanding of the pathologic features and biology of peripheral T cell lymphomas (PTCLs) through development of multi omics and molecular profiling techniques. In addition, international collaborations through multi center trials as well as prospective registry studies have improved our knowledge of host and tumor genomic factors and treatment factors affecting disease outcomes. In our review today, we aim to highlight the current epidemiology, latest advances in classification, disease biology and the evolving treatment landscape for nodal PTCLs.

Yttrium-90 anti-CD25 BEAM conditioning for autologous hematopoietic cell transplantation in Peripheral T-cell lymphoma

ABSTRACT

Peripheral T-cell lymphomas (PTCLs) have a poor prognosis with current treatments. High-dose chemotherapy followed by autologous hematopoietic cell transplant (AHCT) is used as a consolidation strategy after achieving clinical remission with first-line therapy, as well as in chemotherapy-sensitive relapse if allogeneic transplant is not an option. CD25 is a targetable protein often highly expressed in PTCLs. In this phase 1 clinical trial, we tested the addition of β-emitting 90yttrium (90Y)-labeled chimeric anti-CD25 basiliximab (aTac) to BEAM (carmustine, etoposide, cytarabine, and melphalan) as conditioning for AHCT for patients with PTCL. Twenty-three AHCT-eligible patients were enrolled, and 20 received therapeutic 90Y-aTac-BEAM AHCT. Radiation doses of 0.4, 0.5, and 0.6 mCi/kg were tested. With no observed dose-limiting toxicities, 0.6 mCi/kg was deemed the recommended phase 2 dose. The most prevalent adverse effect, grade 2 mucositis, was experienced by 80% of patients. As of this report, 6 (30%) of the treated patients had died, 5 due to progressive disease and 1 due to multiple organ failure (median time of death, 17 months [range, 9-21]) after AHCT. Median follow-up was 24 months (range, 9-26) overall and 24 months (range, 13-26) for surviving patients. For patients who received therapeutic 90Y-aTac-BEAM AHCT, the 2-year progression-free and overall survival were 59% (95% confidence interval [CI], 34-77) and 68% (95% CI, 42-84), respectively. 90Y-aTac-BEAM appears to be safe as an AHCT conditioning regimen for PTCL, with no increased toxicity over the toxicities historically seen with BEAM alone in this patient population. This trial was registered at www.ClinicalTrials.gov as #NCT02342782.

Novel clinical risk stratification and treatment strategies in relapsed/refractory peripheral T-cell lymphoma

Peripheral T cell lymphoma (PTCL) represents a group of heterogeneous hematological malignancies, which are notoriously challenging to treat and outcomes are typically poor. Over the past two decades, clinical prognostic indices for patient risk stratification have evolved, while several targeted agents are now available to complement combination chemotherapy in the frontline setting or as a salvage strategy. With further understanding of the molecular pathobiology of PTCL, several innovative approaches incorporating immunomodulatory agents, epigenetic therapies, oncogenic kinase inhibitors and immunotherapeutics have come to the forefront. In this review, we provide a comprehensive overview of the progress in developing clinical prognostic indices for PTCL and describe the broad therapeutic landscape, emphasizing novel targetable pathways that have entered early phase clinical studies.

Peripheral blood stem cell transplantation using HLA-haploidentical donor with post-transplant cyclophosphamide versus HLA-matched sibling donor for lymphoma

Data comparing HLA-haploidentical donors and HLA-matched sibling donors (MSDs) in peripheral blood stem cell transplantation (PBSCT) for lymphoma are scarce. We retrospectively analyzed 465 patients with lymphoma aged 16 years or older who underwent PBSCT using haploidentical donors with post-transplant cyclophosphamide (PTCy-haplo) (n = 166) or MSDs with calcineurin inhibitor-based graft-versus-host disease (GVHD) prophylaxis (n = 299). Two-year overall survival (OS), progression-free survival (PFS), and GVHD-free, relapse-free survival (GRFS) in the PTCy-haplo and MSD groups were 49.2% versus 51.9% (P = 0.64), 38.0% versus 39.9% (P = 0.97), and 27.7% versus 18.5% (P = 0.006), respectively. In multivariable analyses, PTCy-haplo recipients had slower neutrophil recovery (hazard ratio [HR], 0.62; P < 0.001) and platelet recovery (HR, 0.54; P < 0.001), lower risk of chronic GVHD (HR, 0.64; P = 0.038) and extensive chronic GVHD (HR, 0.45; P = 0.008), and better GRFS (HR, 0.66; P = 0.003) than MSD transplant recipients. OS, PFS, relapse or progression, and non-relapse mortality were similar between the groups. The difference might be mainly due to PTCy use rather than donor type; however, the results suggested that PTCy-haplo could be a possible option as an alternative to conventional MSD transplantation for lymphoma in PBSCT.

Allogeneic stem cell transplant for treatment of mycosis fungoides and Sezary syndrome: a systematic review and meta-analysis

Allogeneic hematopoietic stem cell transplant (allo-HSCT) has been noted to be a potential curative treatment in cases of advanced-stage mycosis fungoides (MF) or Sezary syndrome (SS). To assess outcomes of allo-HSCT for MF/SS we performed a systematic review and meta-analysis including 15 manuscripts and 557 patients, published from 2010-2023. Meta-analysis revealed 1-year and 3+year overall survival (OS) of 51% (95% CI 39-64%) and 40% (32-49%). Progression-free survival at 1 year and 3+years were 42% (31-53%) and 33% (25-42%). Non-relapse mortality was 18% (13-23%). Relapse occurred in of 47% (40-53%) with a median time to relapse of 7.9 months (range 1.6-24 months). Rates of acute and chronic graft-versus-host disease (GVHD) were 45% (35-55%) and 40% (33-48%). Reduced-intensity conditioning (RIC) was associated with superior OS compared to myeloablative conditioning (MAC) (58% vs. 30%, p < 0.001). Of patients with relapse after allo-HSCT, 46% treated with donor lymphocyte infusion (DLI) achieved complete remission. These data support use of allo-HSCT for treatment of advanced-stage MF/SS and suggest superiority of RIC over MAC. Rates of GVHD were comparable to allo-HSCT in general. The improved OS for RIC and high rate of CR with DLI underscore the importance of the graft-versus-lymphoma effect in allo-HSCT for MF/SS.

Advances in the pathogenesis and therapeutic strategies of angioimmunoblastic T-cell lymphoma

Angioimmunoblastic T-cell lymphoma (AITL) is an aggressive subtype of peripheral T-cell lymphomas with its cell origin determined to be follicular helper T-cells. AITL is characterized by a prominent tumor microenvironment involving dysregulation of immune cells, signaling pathways, and extracellular matrix. Significant progress has been made in the molecular pathophysiology of AITL, including genetic mutations, immune metabolism, hematopoietic-derived microenvironment, and non-hematopoietic microenvironment cells. Early diagnosis, detection of severe complications, and timely effective treatment are crucial for managing AITL. Treatment typically involves various combination chemotherapies, but the prognosis is often poor, and relapsed and refractory AITL remains challenging, necessitating improved treatment strategies. Therefore, this article provides an overview of the pathogenesis and latest advances in the treatment of AITL, with a focus on potential therapeutic targets, novel treatment strategies, and emerging immunotherapeutic approaches.

Past, present and future therapeutic approaches in nodal peripheral T-cell lymphomas

Peripheral T-cell lymphomas (PTCL) encompass over 30 different entities and although they share post-thymic T- or NK-cell derivation, the disease biology and genomic landscape are very diverse across subtypes. In Western populations, nodal PTCL are the most frequently encountered entities in clinical practice and although important achievements have been made in deciphering the underlying biology and in therapeutic advances, there are still large gaps in disease understanding and clinical scenarios in which controversy over best practice continues. CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone)- based chemotherapy continues to be the 'standard' treatment, with the addition of brentuximab vedotin (BV) in the combination CHP (cyclosphosphamide, doxorubicin, prednisone)-BV representing a new treatment paradigm in CD30+ PTCL although its benefit is less certain in the non-anaplastic large cell lymphoma subtypes. Given the high risk of relapse, consolidative autologous stem cell transplant is considered in nodal PTCL, outside of ALK-positive anaplastic large cell lymphoma; however, in the absence of a randomized controlled trials, practices vary. Beyond CHP-BV, most study activity has focused on adding a novel agent to CHOP (i.e., CHOP + drug X). However, with high complete remission rates observed with some novel therapy combinations, these regimens are being tested in the front-line setting, with a particular rationale in follicular helper T-cell lymphomas which have a clear sensitivity to epigenetic modifying therapies. This is well exemplified in the relapsed/refractory setting in which rational combination therapies are being developed for specific subtypes or guided by underlying biology. Taken together, we have finally moved into an era of a more personalized approach to the management of nodal PTCL.

Allogeneic hematopoietic stem cell transplantation for NK/T-cell lymphoma: an international collaborative analysis

Natural killer/T-cell lymphomas (NKTCL) represent rare and aggressive lymphoid malignancies. Patients (pts) with relapsed/refractory disease after Asparaginase (ASPA)-based chemotherapy have a dismal prognosis. To better define the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT), we conducted a retrospective analysis of data shared with the European Society for Blood and Marrow Transplantation (EBMT) and cooperating Asian centers. We identified 135 pts who received allo-HSCT between 2010 and 2020. Median age was 43.4 years at allo-HSCT, 68.1% were male. Ninety-seven pts (71.9 %) were European, 38 pts (28.1%) Asian. High Prognostic Index for NKTCL (PINK) scores were reported for 44.4%; 76.3% had >1 treatment, 20.7% previous auto-HSCT, and 74.1% ASPA-containing regimens prior to allo-HSCT. Most (79.3%) pts were transplanted in CR/PR. With a median follow-up of 4.8 years, 3-year progression-free(PFS) and overall survival were 48.6% (95%-CI:39.5-57%) and 55.6% (95%-CI:46.5-63.8%). Non-relapse mortality at 1 year was 14.8% (95%-CI:9.3-21.5%) and 1-year relapse incidence 29.6% (95%-CI:21.9-37.6%). In multivariate analyses, shorter time interval (0-12 months) between diagnosis and allo-HSCT [HR = 2.12 (95%-CI:1.03-4.34); P = 0.04] and transplantation not in CR/PR [HR = 2.20 (95%-CI:0.98-4.95); P = 0.056] reduced PFS. Programmed cell death protein 1(PD-1/PD-L1) treatment before HSCT neither increased GVHD nor impacted survival. We demonstrate that allo-HSCT can achieve long-term survival in approximately half of pts allografted for NKTCL.

Allogeneic Blood or Marrow Transplantation with Post-Transplantation Cyclophosphamide for Peripheral T Cell Lymphoma: The Importance of Graft Source

The use of post-transplantation cyclophosphamide (PTCy) for graft-versus host-disease (GVHD) prophylaxis has revolutionized allogeneic blood or marrow transplantation (alloBMT), but there is limited published experience in peripheral T cell lymphoma (PTCL). We sought to assess outcomes in patients with PTCL who underwent alloBMT with PTCy. We reviewed the charts of all adult patients age ≥18 years who underwent alloBMT with nonmyeloablative conditioning and PTCy-based GVHD prophylaxis at the Sidney Kimmel Comprehensive Cancer Center between January 2004 and December 2020. Sixty-five patients were identified. The median age was 59 years (range, 24 to 75 years). Lymphoma histology included PTCL not otherwise specified (n = 24), anaplastic lymphoma kinase-negative anaplastic large cell lymphoma (n = 14), angioimmunoblastic T cell lymphoma (n = 7), enteropathy-associated T cell lymphoma (n = 6), hepatosplenic T cell lymphoma (n = 4), and others (n = 10). Eleven patients were in first complete remission (17%); the remaining patients were in first partial remission or underwent salvage therapy to at least PR prior to transplantation. Forty-eight patients underwent alloBMT from a haploidentical related donor (74%), 10 from a fully matched donor (15%), and 7 from a mismatched unrelated donor (11%). All patients received fludarabine, cyclophosphamide, and total body irradiation (TBI). The graft source was bone marrow (BM) in 46 patients (71%) and peripheral blood (PB) in 19 patients (29%); all patients in the BM cohort received 200 cGy TBI, and most patients in the PB cohort (15 of 19) received 400 cGy TBI. GVHD prophylaxis comprised PTCy, mycophenolate mofetil, and a calcineurin inhibitor or sirolimus. With a median follow-up of 2.8 years (range, 290 days to 14.2 years), the 2-year progression-free survival (PFS) for the entire cohort was 49% (95% confidence interval [CI], 38% to 64%), and the 2-year overall survival (OS) was 55% (95% CI, 44% to 69%). Outcomes were significantly improved in those receiving PB compared to those receiving BM, including a 2-year PFS of 79% (95% CI 63% to 100%) versus 39% (95% CI, 27% to 56%), 2-year OS of 84% (95% CI, 69% to 100%) versus 46% (95% CI, 33% to 63%), and 1-year cumulative incidence of relapse of 5% (95% CI, 0 to 16%) versus 33% (95% CI, 19% to 46%), with no difference in GVHD and nonrelapse mortality. AlloBMT with PTCy is safe and well-tolerated in patients with PTCL. Our data suggest that increasing the TBI dose to 400 cGy and using PB allografts may offer improved disease control and better survival outcomes, though additional studies are needed to confirm these findings.

Haploidentical Versus Matched Unrelated Donor Transplants Using Post-Transplantation Cyclophosphamide for Lymphomas

When using post-transplantation cyclophosphamide (PTCy) graft-versus-host disease (GVHD) prophylaxis for lymphoma patients, it is currently unknown whether a matched unrelated donor (MUD) or a haploidentical related donor is preferable if both are available. In this study we wanted to test whether using a haploidentical donor has the same results of a MUD. A total of 2140 adults (34% Center for International Blood and Marrow Transplant Research, 66% European Society for Blood and Marrow Transplantation registry) aged ≥18 years who received their first haploidentical hematopoietic cell transplantation (haplo-HCT) or MUD-HCT (8/8 match at HLA-loci A, B, C, and DRB1) for lymphoma using PTCy-based GVHD prophylaxis from 2010 to 2019 were retrospectively analyzed. The majority of both MUD and haploidentical HCTs received reduced intensity/nonmyeloablative conditioning (74% and 77%, respectively) and used a peripheral blood stem cell graft (91% and 60%, respectively) and a 3-drug GVHD prophylaxis (PTCy + calcineurin inhibitor + MMF in 54% and 90%, respectively). Haploidentical HCT has less favorable results versus MUD cohort in terms of overall mortality (hazard ratio [HR= = 1.69; 95% confidence interval [CI], 1.30-2.27; P < .001), progression-free survival (HR=1.39; 95% CI, 1.10-1.79; P = .008), nonrelapse mortality (HR = 1.93; 95% CI, 1.21-3.07; P = .006), platelet engraftment (HR = 0.69; 95% CI, 0.59-0.80; P < .001), acute grade 2-4 GVHD incidence (HR = 1.65; 95% CI, 1.28-2.14; P < .001), and chronic GVHD (HR = 1.79; 95% CI, 1.30-2.48, P < .001). No significant differences were observed in terms of relapse and neutrophil engraftment. Adjusting for propensity score yielded similar results. Whenever MUD is available in a timely manner, it should be preferred over a haploidentical donor when using PTCy-based GVHD prophylaxis for patients with lymphoma.

Therapeutic Advances in Relapsed and Refractory Peripheral T-Cell Lymphoma

Historic outcomes for patients with relapsed or refractory nodal-based T-cell lymphomas are poor, with survival generally measured in months in multiple reports from the late 20th and early 21st century. Until recently, salvage strategies have mostly been borrowed from other aggressive lymphomas. However, dedicated investigations into the pathogenesis of T-cell lymphomas have resulted in an outpouring of therapies that target these diseases in biologically rational strategies. In particular, an evolving appreciation of the multiple complex oncogenic pathways and epigenetic changes that underlie these diseases has led to numerous agents targeting these aberrancies. Moreover, large reports of salvage allogeneic stem cell transplants in T-cell lymphoma have now been published, showing that adaptive immunotherapy is a potentially curative strategy for patients with relapsed or refractory disease. This review highlights therapeutic advances for relapsed or refractory T-cell lymphomas, including cellular therapy and allogeneic stem cell transplant, and provides a framework for management.

Romidepsin-CHOEP followed by high-dose chemotherapy and stem-cell transplantation in untreated Peripheral T-Cell Lymphoma: results of the PTCL13 phase Ib/II study

The standard treatment for young patients with untreated PTCLs is based on anthracycline containing-regimens followed by high-dose-chemotherapy and stem-cell-transplantation (HDT + SCT), but only 40% of them can be cured. Romidepsin, a histone-deacetylase inhibitor, showed promising activity in relapsed PTCLs; in first line, Romidepsin was added with CHOP. We designed a study combining romidepsin and CHOEP as induction before HDT + auto-SCT in untreated PTCLs (PTCL-NOS, AITL/THF, ALK-ALCL), aged 18-65 years. A phase Ib/II trial was conducted to define the maximum tolerated dose (MTD) of Ro-CHOEP, and to assess efficacy and safety of 6 Ro-CHOEP as induction before HDT. The study hypothesis was to achieve a 18-month PFS of 70%. Twenty-one patients were enrolled into phase Ib; 7 dose-limiting toxicities were observed, that led to define the MTD at 14 mg/ms. Eighty-six patients were included in the phase II. At a median follow-up of 28 months, the 18-month PFS was 46.2% (95%CI:35.0-56.7), and the 18-month overall survival was 73.1% (95%CI:61.6-81.7). The overall response after induction was 71%, with 62% CRs. No unexpected toxicities were reported. The primary endpoint was not met; therefore, the enrollment was stopped at a planned interim analysis. The addition of romidepsin to CHOEP did not improve the PFS of untreated PTCL patients.

Allogeneic haematopoietic cell transplant in patients with relapsed/refractory anaplastic large cell lymphoma

The prognosis of relapsed/refractory (R/R) anaplastic large cell lymphoma (ALCL) is poor. Large studies evaluating outcomes of allogeneic haematopoietic cell transplantation (allo-HCT) in systemic R/R ALCL are not available. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we evaluated outcomes of 182 adults (aged ≥18 years) with R/R ALCL undergoing allo-HCT between 2008 and 2019. Non-relapse mortality (NRM), disease relapse/progression (REL), progression-free survival (PFS), and overall survival (OS) were modelled using Cox proportional hazards models. The median (range) follow-up of survivors was 62 (3-148) months. The 1-year NRM was 18%. The 5-year REL, PFS and OS were 32%, 41% and 56% respectively. On multivariable regression analysis African American race (hazard ratio [HR] 2.7, 95% confidence interval [CI] 1.6-4.8; p < 0.001) and refractory disease at allo-HCT (HR 3.2, 95% CI 1.6-6.2; p < 0.001) were predictive of inferior OS. Similarly, African-American race (HR 2.1, 95% CI 1.3-3.4; p = 0.003), other minority race (HR 2.5, 95% CI 1.2-5.3; p = 0.02) and refractory disease (HR 2.2, 95% CI 1.2-4.3; p = 0.01) were predictive of inferior PFS. These data, demonstrate that allo-HCT can result in durable disease control in a sizable proportion of patients with R/R ALCL. Refractory disease and racial minority status predicted inferior allo-HCT outcomes. Whether the inferior outcomes of racial minorities with R/R ALCL after allo-HCT are driven by differences in disease biology or disparities in post allo-HCT care, or both, requires further investigation.

Controversies in the Front-Line Treatment of Systemic Peripheral T Cell Lymphomas

Systemic peripheral T cell lymphomas (PTCL) are a rare and clinically and biologically heterogeneous group of disorders with scarce and generally low-quality evidence guiding their management. In this manuscript, we tackle the current controversies in the front-line treatment of systemic PTCL including (1) whether CNS prophylaxis should be administered; (2) whether CHOEP should be preferred over CHOP; (3) what role brentuximab vedotin should have; (4) whether stem cell transplant (SCT) consolidation should be used and whether autologous or allogeneic; (5) how should molecular subtypes (including DUSP22 or TP63-rearranged ALCL or GATA3 or TBX21 PTCL, NOS) impact therapeutic decisions; and (6) whether there is a role for targeted agents beyond brentuximab vedotin.

Management of Peripheral T-cell Lymphomas and the Role of Transplant

PURPOSE OF REVIEW

Here, we review the management of peripheral T-cell lymphoma, particularly focusing on the role of autologous and allogeneic stem cell transplant.

RECENT FINDINGS

Peripheral T-cell lymphomas are a rare subset of non-Hodgkin's lymphomas that are treated with curative intent. While therapy has been based on other aggressive lymphoid malignancies, outcomes are generally poorer than B-cell lymphomas with 5-year overall and progression-free survival of 30-40% and 20-30%, respectively. In effort to improve outcomes, transplant has been used in both the frontline and salvage settings. Although not studied in randomized studies, consolidation with autologous stem cell transplant in first remission has been associated with an approximate 5-year overall survival of 50-60% and 5-year progression-free survival of 40-45%. Unfortunately, most patients relapse, and, in this setting, allogeneic transplant remains the only curative option for those who are transplant-eligible. Multiple series have now shown that 3-year overall survival with allogeneic transplant is approximately 60%. However, outcomes with transplant are associated with disease control at the time of transplant. In contrast to B-cell malignancies, treatment decisions for peripheral T-cell lymphomas are supported mostly by phase II studies, retrospective series, and expert opinion. For patients with peripheral T-cell lymphoma able to achieve sufficient disease control, autologous stem cell transplantation in first remission and allogeneic stem cell transplantation in relapsed disease offer modest benefit over chemotherapy alone.