Treatment of relapsed adult T-cell leukemia/lymphoma after allogeneic hematopoietic stem cell transplantation: the Nagasaki Transplant Group experience

Chemotherapy and allo-HSCT for young patients with aggressive ATL

Adult T-cell leukemia-lymphoma (ATL) is an aggressive malignancy with a poor prognosis, especially for patients with the aggressive subtype. While conventional chemotherapy offers short-term disease control, allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the most promising curative approach for young, transplant-eligible patients. This review focuses on current treatment strategies for aggressive ATL in this specific population. We discuss the rationale for early upfront allo-HSCT following induction chemotherapy. The advent of allo-HSCT using alternative donors, particularly haploidentical HCT, has broadened the applicability of early upfront allo-HSCT in patients with aggressive ATL worldwide. Finally, we address emerging therapies that may improve outcomes in the context of allo-HSCT, paving the way for further advancements in the treatment of aggressive ATL.

Modified Prophylactic Donor Lymphocyte Infusion (DLI) in an Adult T Cell Lymphoma/Leukemia (ATLL) Patient-Modality of Relapse Prevention

Adult T-cell Leukemia/Lymphoma (ATLL) is a rare but aggressive malignancy associated with the human T-cell lymphotropic virus type 1 (HTLV-1). ATLL is a challenging malignancy characterized by its aggressive nature and poor prognosis. Despite advancements in treatment, relapse rates remain high. Donor lymphocyte infusion (DLI) is a promising therapeutic option post-hematopoietic stem cell transplantation (HSCT) to prevent relapse. However, the prophylactic use of DLI in ATLL patients remains underexplored. We report the case of a 45-year-old female diagnosed with ATLL. Following induction chemotherapy and successful HSCT, a modified prophylactic DLI regimen was administered, consisting of gradually increasing doses of donor lymphocytes. The patient demonstrated a favorable response with no significant graft-versus-host disease (GVHD) and maintained remission over a 40-month follow-up period, suggesting a potential benefit of this approach. This case highlights the potential efficacy and safety of modified prophylactic DLI in ATLL patients, warranting further investigation. Our findings suggest that modified prophylactic DLI is a viable option for ATLL patients post-HSCT, offering a balance between efficacy and safety. Future research should focus on optimizing DLI protocols and exploring biomarkers for response prediction.

Case report: Preventive infusion of donor-derived CD7 chimeric antigen receptor T cells after allogeneic hematopoietic stem cell transplantation

Chimeric antigen receptor T cells (CAR T) targeting CD7 for T-cell acute lymphoblastic leukemia/lymphoma (T-ALL/LBL) showed promising efficacy and safety in some clinical trials. However, most of them were bridged with allogeneic hematopoietic stem cell transplantation (allo-HSCT). We described successful treatment with preventive donor-derived anti-CD7 CAR-T therapy in a case of refractory T lymphoblastic lymphoma following allo-HSCT, who could not receive autologous anti-CD7 CAR-T products due to the low-quality of T lymphocytes. To date, the patient's complete remission has persisted for 20 months after HSCT.

Outcome of Stem Cell Transplantation in HTLV-1-Associated North American Adult T-Cell Leukemia/Lymphoma

Adult T-cell leukemia/lymphoma (ATLL) remains challenging to treat and has dismal outcome. Allogeneic stem-cell transplantation (allo-SCT) has promising results, but data remain scarce. In this single-center retrospective analysis of 100 patients with ATLL from north America (67 acute, 22 lymphomatous), 17 underwent allo-SCT and 5 autologous SCT (ASCT), with a median follow-up of 65 months. Post-transplant 3-years relapse incidence (RI) and non-relapse mortality (NRM) were 51% and 37%, respectively, and 3-year progression-free survival (PFS) and overall survival (OS) were 31% and 35%, respectively. ASCT 1-year RI was 80% compared to 30% in allo-SCT (p = 0.03). After adjusting for immortal-time bias, allo-SCT had significantly improved OS (HR = 0.4, p = 0.01). In exploratory multivariate analysis, patients achieving first complete response and Karnofsky score ≥ 90 had significantly better outcomes, as did Black patients, compared to Hispanics, who had worse outcome. In transplanted patients, 14 died within 2 years, 4 of which ASCT recipients. Our data are the largest ATLL transplant cohort presented to date outside of Japan and Europe. We show that allo-SCT, but not ASCT, is a valid option in select ATLL patients, and can induce long term survival, with 40% of patients alive after more than 5 years.

Mogamulizumab for post-transplant relapse of adult T-cell leukemia/lymphoma: a case study

Mogamulizumab (MOG), a humanized monoclonal anti-CCR4 antibody, exerts strong antibody-dependent cellular cytotoxic effects on CCR4-positive adult T-cell leukemia/lymphoma (ATLL) cells. As CCR4 is highly expressed on regulatory T cells as well as ATLL cells, pre-transplant MOG induces severe graft-versus-host disease (GvHD). However, limited data are available on post-transplant use of MOG for relapsed ATLL. Here we describe the case of a patient with ATLL who experienced post-transplant relapse with involvement of peripheral blood, skin, lungs, and lymph nodes. Neither tacrolimus dose reduction nor cytotoxic chemotherapy was effective, but a single dose of MOG (1 mg/kg) induced complete remission. After treatment with MOG, leukemic cells in the peripheral blood rapidly disappeared, and the skin, lymph node, and lung lesions gradually regressed. Most notably, the long-term remission was accompanied by recurrence of moderate acute GvHD (grade II, skin stage 2, gut stage 1, liver stage 0). Our findings indicate that MOG can augment allogeneic immune-mediated anti-tumor reactions through graft-versus-ATLL (GvATLL) even during post-transplant relapse involving the lymph nodes and lungs, along with inducing GvHD.

Clinical features of non-infectious pulmonary complications after donor lymphocyte infusion in post-transplant patients: The Nagasaki Transplant Group Experience

Donor lymphocyte infusion (DLI) is a therapeutic modality for relapsed hematological malignancies after allogeneic hematopoietic stem cell transplantation. We retrospectively analyzed non-infectious pulmonary complications (non-IPCs) following DLI therapy in 41 post-transplant patients with hematological malignancies, and found that 7 developed post-DLI non-IPCs. The 6-year cumulative incidence of non-IPCs was 18.0%. In these patients, non-IPCs were classified into three subtypes: acute respiratory distress syndrome (ARDS), nonspecific interstitial pneumonia (NSIP), and bronchiolitis obliterans syndrome (BOS). The median intervals from the last date of DLI to the development of ARDS and BOS were 12 days (range, 12-14) and 9.4 months (range, 2.6-61.8), respectively; the intervals between DLI and the development of NSIP were 3.5 and 24.7 in 2 patients. Regarding the status of GVHD before the diagnosis with ARDS, 2 out of 3 patients showed the progression of acute GVHD following DLI therapy. One out of 2 patients with NSIP and all 3 patients with BO had chronic GVHD symptoms prior to the development of non-IPCs. In our cohort, 1 patient died of the progression of NSIP. In conclusion, the present study showed the clinical features of non-IPCs following DLI, suggesting the importance of careful follow-ups for non-IPCs in post-DLI patients.

Prognostic value of pre-transplantation total metabolic tumor volume on 18fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography in relapsed and refractory aggressive lymphoma

Relapsed and refractory aggressive lymphoma have a poor prognosis. High-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (auto-HSCT) is effective in chemosensitive patients. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is among the few options for non-chemosensitive patients. ¹⁸Fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography (¹⁸FDG-PET/CT) is the standard tool for evaluating response to chemotherapy and residual tumor volume. However, accurate assessment of residual tumor volume is not currently being achieved in clinical practice, and its value in prognostic and therapeutic stratification remains unclear. To answer this question, we investigated the efficacy of quantitative indicators, including total metabolic tumor volume (TMTV), in predicting prognosis after auto-HSCT and allo-HSCT. We retrospectively analyzed 39 patients who received auto-HSCT and 28 who received allo-HSCT. In the auto-HSCT group, patients with a higher TMTV had a poor prognosis due to greater risk of relapse. In the allo-HSCT group, patients with a higher TMTV had a lower progression-free survival rate and a significantly higher relapse rate. Neither Deauville score nor other clinical parameters were associated with prognosis in either group. Therefore, pre-transplant TMTV on PET is effective for prognostic prediction and therapeutic decision-making for relapsed or refractory aggressive lymphoma.

Systematic review of survival outcomes for relapsed or refractory adult T-cell leukemia-lymphoma

Introduction

Adult T‐cell leukemia‐lymphoma (ATL) is a mature T‐cell lymphoproliferative neoplasm caused by human T‐cell leukemia virus type‐1 infection. There is no standard treatment for relapsed or refractory (r/r) ATL, and clinical outcomes are poor. This systematic review examined the survival outcomes for r/r ATL treated with various systemic therapies.

Methods

EMBASE and PubMed were searched for studies on r/r ATL, published between January 2010 and January 2020. The main outcome of interest was overall survival (OS). Median OS and an exploratory 30% OS time were assessed based on published data and Kaplan‐Meier curves.

Results

There were 21 unique treatment subgroups (from 14 studies), that met the eligibility criteria. Nine subgroups were mogamulizumab treatment, two were mogamulizumab prior to allogenic hematopoietic stem cell transplantation (allo‐HSCT), five were allo‐HSCT, and five were other chemotherapy. Respectively, the median OS and 30% OS varied considerably in range for mogamulizumab treatment (2.2–17.6 months and 8.7–27.1 months), allo‐HSCT (3.8–6.2 months and 7.5–19.8 months), and other chemotherapy arms (4.1–20.3 months and 7.1–17.0 months).

Conclusion

Mogamulizumab was the most frequently studied treatment regimen and can potentially provide longer survival compared with chemotherapy alone. Future comparisons with synthetic or historical control arms may enable clearer insights into treatment efficacy.

Allogeneic hematopoietic stem cell transplantation for adult T-cell leukemia/lymphoma with HTLV-1-associated myelopathy

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) can be curative for adult T-cell leukemia/lymphoma (ATL), but comorbidities increase transplant-related mortality. Here we report the outcome of allo-HSCT in a patient with ATL with human T-cell leukemia virus type I (HTLV-1)-associated myelopathy-tropical spastic paraparesis (HAM/TSP). A 48-year-old man was diagnosed with HAM/TSP and started prednisolone therapy. Ten years later, he developed lymphoma-type ATL. At the diagnosis of ATL, Osame's Motor Disability Score (OMDS) was 4. When prednisolone was gradually tapered and stopped following chemotherapy for ATL, HAM/TSP symptoms recurred (OMDS 7). Bone marrow transplantation from a human leukocyte antigen allele 8/8 matched unrelated donor was performed while ATL was in partial remission. Neutrophil engraftment with complete donor chimerism was achieved on day 19 after allo-HSCT. Mild gait improvement (OMDS 5) was observed on day 30. Although ATL relapsed on day 275, progression of HAM/TSP symptoms was not observed. Furthermore, there was no clear progression of HAM/TSP symptoms after donor lymphocyte infusions. The outcome of this case suggests that ATL patients with HAM/TSP tolerate allo-HSCT and donor lymphocyte infusions.

Allogeneic Stem Cell Transplantation for Adult T-Cell Leukemia/Lymphoma-Romanian Experience

Adult T-cell leukemia/lymphoma (ATLL) is a rare and aggressive mature T-cell malignancy caused by the human T lymphoma virus I (HTLV-I) affecting 3–5% of HTLV-1 carriers and is usually diagnosed in endemic regions. Romania is a region with high prevalence of HTLV-1 infection and ATLL and with low median age at diagnosis for aggressive types. We performed a retrospective analysis of post-transplant outcome in the first Romanian patients with ATLL receiving hematopoietic stem cell allotransplant. The study population included eight patients (three males, five females), with median age of 39.5 (range 26–57), with acute (one case) and lymphoma type (seven cases) that received peripheral stem cells (PBSC) from matched related (MRD) and unrelated donors (MUD) after reduced intensity conditioning. Graft versus host disease (GVHD) developed in six patients. Relapse occurred in four cases (50%) at a median time of 5-months post-transplant. Six patients died: four cases with disease-related deaths and two patients with GVHD-related deaths. The median survival post-transplant was 19.5 months (range 2.3–44.2 months). The post-transplant survival at 1-year was 62.5%, at 2-years 50%, and at 3-years 37.5%. In our opinion allogeneic transplant improves outcome in aggressive type ATLL.

Diagnostic Approaches and Established Treatments for Adult T Cell Leukemia Lymphoma

Adult T-cell leukemia-lymphoma (ATL) is a distinct mature T-cell malignancy caused by human T-cell leukemia/lymphotropic virus type I (HTLV-1) endemic in some areas in the world. HTLV-1 transmits through mother-to-child infection via breastfeeding, sexual intercourses, and blood transfusions. Early HTLV-1 infection, presumably through mother’s milk, is crucial in developing ATL. The estimated cumulative risk of the development of ATL in HTLV-1 carriers is a few percent after transmission from their mothers. The median age of ATL onset is about 70 in Japan and is now rising, whereas an overall mean age in the mid-forties is reported in other parts of the world. ATL is classified into four clinical subtypes (acute, lymphoma, chronic, and smoldering) defined by organ lesions and LDH/calcium values. In aggressive ATL (acute, lymphoma or unfavorable chronic types) and indolent ATL (favorable chronic or smoldering types), intensive chemotherapy followed by allogeneic hematopoietic stem cell transplantation and watchful waiting until disease progression has been recommended, respectively, in Japan. Based on a worldwide meta-analysis and multiple other retrospective studies, the antiviral combination of interferon alpha (IFN) and zidovudine (AZT) is recommended in many parts of the world in acute, chronic, and smoldering ATL whereas patients with the lymphoma subtype are treated with chemotherapy, either alone or combined with AZT/IFN. Several new agents have been approved for ATL by the Pharmaceutical and Medical Devices Agency (PMDA) after clinical trials, including an anti-CC chemokine receptor 4 monoclonal antibody, mogamulizumab; an immunomodulatory agent, lenalidomide; and an anti-CD30 antibody/drug conjugate, brentuximab vedotin.

Treatment with mogamulizumab or lenalidomide for relapsed adult T-cell leukemia/lymphoma after allogeneic hematopoietic stem cell transplantation: The Nagasaki transplant group experience

Mogamulizumab (Mog) and lenalidomide (Len) are new therapeutic candidates for relapsed adult T-cell leukemia/lymphoma after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In the present study, we retrospectively analyzed 12 patients who received Mog or Len monotherapy for relapsed ATL after allo-HSCT. Eight and three patients received Mog and Len, respectively. The remaining patient received Mog for the first relapse and Len for the third relapse. A complete response was achieved by three and two patients who received Mog and Len, respectively, two and one of whom remained alive with a complete response for more than 20 months. In terms of adverse events, the emergence or progression of graft-versus-host disease was observed in three out of four patients treated with Len and in none of the patients treated with Mog. The development or progression of cytomegalovirus reactivation was detected in four out of eight patients treated with Mog and in none of those treated with Len. The present results suggest that Mog and Len would be promising treatment options for relapsed ATL after allo-HSCT and need to be selected based on adverse event profiles.

Progress in Allogeneic Hematopoietic Cell Transplantation in Adult T-Cell Leukemia-Lymphoma

The prognosis of aggressive adult T-cell leukemia-lymphoma (ATL) remains poor because of frequent infections and drug resistance. Dose-intensified chemotherapy followed by autologous stem cell transplantation failed to improve the prognosis of patients with ATL; however, we first revealed that allogeneic hematopoietic cell transplantation (allo-HCT) might improve their prognosis. We showed that reduced-intensity stem cell transplantation using peripheral blood was feasible for elderly patients. Further, the prognosis of patients in remission, who receive cord blood transplantation, has been recently improved and is equivalent to that of patients who receive transplants from other stem cell sources. As for the timing of HCT, the patients who underwent transplantation early showed better outcomes than those who underwent transplantation late. Based on the analysis of patients with aggressive ATL, including those who received transplants, we identified five prognostic factors for poor outcomes: acute-type ATL, poor performance status, high soluble interleukin-2 receptor levels, hypercalcemia, and high C-reactive protein level. Next, we developed a new prognostic index: the modified ATL-PI. The overall survival (OS) rates were significantly higher in patients who underwent allo-HCT than those who did not in the intermediate and high-risk groups stratified using the modified ATL-PI. Two new anti-cancer agents, mogamulizumab and lenalidomide, were recently approved for ATL patients in Japan. They are expected to induce longer survival in ATL patients when administered along with transplantation. However, a retrospective analysis that the risk of severe, acute, and corticosteroid-refractory graft-versus-host disease was higher in patients who received mogamulizumab before allo-HCT, and that mogamulizumab might increase the transplant-related mortality (TRM) rates and decrease the OS rates compared to those of patients who did not receive mogamulizumab. However, our recent study showed that administration of mogamulizumab before allo-HCT tended to improve the survival of patients with ATL. In conclusion, allo-HCT procedures for patients with aggressive ATL have considerably progressed and have helped improve the prognosis of these patients; however, many concerns still remain to be resolved. Further development of allo-HCT by using new molecular targeting agents is required for the improvement of cure rates in patients with ATL.

Revised Adult T-Cell Leukemia-Lymphoma International Consensus Meeting Report

PURPOSE

Adult T-cell leukemia-lymphoma (ATL) is a distinct mature T-cell malignancy caused by chronic infection with human T-lymphotropic virus type 1 with diverse clinical features and prognosis. ATL remains a challenging disease as a result of its diverse clinical features, multidrug resistance of malignant cells, frequent large tumor burden, hypercalcemia, and/or frequent opportunistic infection. In 2009, we published a consensus report to define prognostic factors, clinical subclassifications, treatment strategies, and response criteria. The 2009 consensus report has become the standard reference for clinical trials in ATL and a guide for clinical management. Since the last consensus there has been progress in the understanding of the molecular pathophysiology of ATL and risk-adapted treatment approaches.

METHODS

Reflecting these advances, ATL researchers and clinicians joined together at the 18th International Conference on Human Retrovirology-Human T-Lymphotropic Virus and Related Retroviruses-in Tokyo, Japan, March, 2017, to review evidence for current clinical practice and to update the consensus with a new focus on the subtype classification of cutaneous ATL, CNS lesions in aggressive ATL, management of elderly or transplantation-ineligible patients, and treatment strategies that incorporate up-front allogeneic hematopoietic stem-cell transplantation and novel agents.

RESULTS

As a result of lower-quality clinical evidence, a best practice approach was adopted and consensus statements agreed on by coauthors (> 90% agreement).

CONCLUSION

This expert consensus highlights the need for additional clinical trials to develop novel standard therapies for the treatment of ATL.

Prognostic importance of pretransplant disease status for posttransplant outcomes in patients with adult T cell leukemia/lymphoma

Adult T cell leukemia/lymphoma (ATL) is an aggressive T cell lymphoma with a poor prognosis. Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) can be a curative treatment for ATL, a significant proportion of allo-HSCT recipients suffer from relapse/progression of ATL. Here we aimed to clarify the risk factors for and outcomes after posttransplant relapse/progression. We retrospectively reviewed 76 patients with ATL who received allo-HSCT at our institute. At the time of allo-HSCT, disease status was complete response in 17 patients, partial response in 29, stable disease (SD) in 18, and progressive disease (PD) in 12. In multivariate analysis, SD/PD at allo-HSCT, lymphoma subtype, reduced-intensity conditioning regimen, and time from diagnosis to allo-HSCT were associated with risk of relapse/progression. After allo-HSCT, 26 patients had relapse/progression at a median of 66 days (range, 13–2064 days). The 2-year overall survival rate after relapse/progression was only 19%. Compared with acute-type, lymphoma-type experienced local recurrence more frequently (1/15 acute vs. 7/11 lymphoma, P < 0.01) and had a significantly longer OS after relapse/progression (median; 112 days in acute vs. 554 days in lymphoma, P < 0.01). Since the prognosis of patients with ATL who experienced relapse/progression after allo-HSCT was poor, strategies to reduce the risk of these outcomes are warranted.

Autologous and Allogeneic Hematopoietic Cell Transplantation in Peripheral T/NK-cell Lymphomas: A Histology-Specific Review

Peripheral T-cell lymphoma and natural killer/T-cell lymphomas (PT/NKCL) make up a diverse subgroup of non-Hodgkin's lymphomas characterized by an aggressive clinical course. The use of hematopoietic stem cell transplantation (HSCT) in the treatment of PT/NKCL remains controversial because of the absence of randomized controlled trials. The best available data suggest that certain subtypes of PT/NKCL may benefit more from the application of HSCT than other subtypes and that this benefit results from their unique clinical characteristics and underlying biology. Ultimately, however, prospective randomized controlled trials are needed to clarify the optimal type and timing of HSCT in patients with PT/NKCL.

Overview of Targeted Therapies for Adult T-Cell Leukemia/Lymphoma

Adult T-Cell Leukemia/lymphoma (ATL) is the first human malignancy associated with a chronic infection by a retrovirus, the human T-cell lymphotropic virus type I (HTLV-I). ATL occurs, after a long latency period, only in about 5% of 10-20 millions infected individuals. ATL has a dismal prognosis with a median survival of less than 1 year, mainly due to its resistance to chemotherapy and to a profound immunosuppression. The viral oncoprotein, Tax, plays a major role in ATL oncogenic transformation by interfering with cell proliferation, cell cycle, apoptosis, and DNA repair. The diversity in ATL clinical features and prognosis led to Shimoyama classification of ATL into four clinical subtypes (acute, lymphoma, chronic, and smoldering) requiring different therapeutic strategies. Clinical trials, mainly conducted in Japan, demonstrated that combination of chemotherapy could induce acceptable response rate in the lymphoma subtype but not in acute ATL. However, long-term prognosis remains poor for both subtypes, due to a high relapse rate. Similarly, whether managed by a watchful waiting or treated with chemotherapy, the indolent forms (smoldering and chronic) have a poor long-term outcome. An international meta-analysis showed improved survival in the leukemic subtypes of ATL (chronic, smoldering as well as a subset of the acute subtype) with the use of two antiviral agents, zidovudine and interferon-alpha, and accordingly, this combination should be considered the standard first-line treatment in this context. ATL patients with lymphoma subtype benefit from induction chemotherapy, given simultaneously or sequentially with an antiviral combination of zidovudine and interferon-alpha. Allogeneic hematopoietic stem cells transplantation remains a promising and potentially curative approach but is limited to a small number of patients. Novel drugs such as arsenic trioxide in combination with interferon-alpha or monoclonal antibodies such as anti-CXCR4 have shown promising results and warrant further investigation.

Striving to cure adult T-cell leukaemia/lymphoma: a role for allogeneic stem cell transplant?

Adult T-cell leukaemia/lymphoma (ATL) is an aggressive HTLV-1-related malignancy, rare outside of regions where the retrovirus is endemic. Although the use of antiviral therapy has improved outcomes, particularly for indolent forms of ATL, response to combination chemotherapy is poor and outcomes for aggressive subtypes remains dismal. Consolidation with allogeneic stem cell transplant (alloSCT) has an increasing role in the management of ATL in eligible patients, offering favourable long-term remission rates. However, relatively high-transplant-related mortality and issues with donor recruitment for certain ethnicities remain problematic. In this review, we discuss the rationale for and issues surrounding alloSCT in ATL in the context of conventional and emerging therapies.

Cord Blood Transplantation Provided Long-term Remission in a Case of Adult T-cell Leukemia-lymphoma (ATL) with Myelofibrosis

A 53-year-old man was diagnosed with adult T-cell leukemia-lymphoma (ATL) acute type transformed from chronic type. A bone marrow analysis showed diffuse infiltration of abnormal lymphocytes and diffuse fibrotic change. He received unrelated cord blood transplantation (CBT) following reduced-intensity conditioning with complete remission of ATL after two courses of chemotherapy and achieved neutrophil and platelet engraftment. At 99 days after CBT, a bone marrow biopsy showed apparent resolution of myelofibrosis. These results suggest the therapeutic potential of CBT for patients with chemosensitive ATL with myelofibrosis.

Recent Advances in Therapeutic Approaches for Adult T-cell Leukemia/Lymphoma

Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell lymphoma caused by human T-cell leukemia/lymphoma virus type 1 (HTLV-1). ATLL occurs in approximately 3%–5% of HTLV-1 carriers during their lifetime and follows a heterogeneous clinical course. The Shimoyama classification has been frequently used for treatment decisions in ATLL patients, and antiviral therapy has been reportedly promising, particularly in patients with indolent type ATLL; however, the prognosis continues to be dismal for patients with aggressive-type ATLL. Recent efforts to improve treatment outcomes have been focused on the development of prognostic stratification and improved dosage, timing, and combination of therapeutic modalities, such as antiviral therapy, chemotherapy, allogeneic hematopoietic stem cell transplantation, and molecular targeted therapy.

Effect of immune modulation in relapsed peripheral T-cell lymphomas after post-allogeneic stem cell transplantation: a study by the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC)

Peripheral T-cell lymphoma carries a poor prognosis. To document a possible graft-versus-lymphoma effect in this setting, we evaluated the impact of immunomodulation in 63 patients with peripheral T-cell lymphoma who relapsed after allogeneic transplant in 27 SFGM-TC centers. Relapse occurred after a median of 2.8 months. Patients were then treated with non-immunologic strategies (chemotherapy, radiotherapy) and/or immune modulation (donor lymphocyte infusions (DLI) and/or discontinuation of immunosuppressive therapy). Median overall survival (OS) after relapse was 6.1 months (DLI group: 23.6 months, non-DLI group: 3.6 months). Among the 14 patients who received DLI, 9 responded and 2 had stable disease. Among the remaining 49 patients, a complete response accompanied by extensive chronic GvHD was achieved in two patients after tapering of immunosuppressive drugs. Thirty patients received radio-chemotherapy, with an overall response rate of 50%. In multivariate analysis, chronic GvHD (odds ratio: 11.25 (2.68-48.21), P=0.0009) and skin relapse (odds ratio: 4.15 (1.04-16.50), P=0.043) were associated with a better response to treatment at relapse. In a time-dependent analysis, the only factor predictive of OS was the time from transplantation to relapse (hazards ratio: 0.33 (0.17-0.640), P=0.0009). This large series provides encouraging evidence of a true GvL effect in this disease.

Optimizing Management of Patients with Adult T Cell Leukemia-Lymphoma

Adult T cell leukemia-lymphoma is a rare disease with a high mortality rate, and is challenging for the clinician. Early allogeneic stem cell transplant can confer durable remission. As novel therapeutic agents become available to treat T cell malignancies, it is increasingly important that medical oncologists, hematologists, and hematopathologists recognize and accurately diagnose adult T cell leukemia-lymphoma. There is no uniform standard of treatment of adult T cell leukemia-lymphoma, and clinical trials remain critical to improving outcomes. Here we present one management approach based on the recent advances in treatment for adult T cell leukemia-lymphoma patients.

Prognostic Significance of Tryptophan Catabolism in Adult T-cell Leukemia/Lymphoma

PURPOSE

Indoleamine 2,3-dioxygenase 1 (IDO1: IDO), an enzyme catabolizing tryptophan (Trp) into the kynurenine (Kyn) pathway, is increasingly being recognized as an important microenvironmental factor suppressing antitumor immune responses. The purpose of the present study was to determine the prognostic significance of Trp catabolism in adult T-cell leukemia/lymphoma (ATL).

EXPERIMENTAL DESIGN

We quantified serum Trp and Kyn in 96 ATL patients, 38 human T-cell lymphotropic virus type-1 asymptomatic carriers (HTLV-1 ACs), and 40 healthy adult volunteer controls. The relationships between various clinical parameters including overall survival were analyzed. IDO expression was evaluated in the affected lymph nodes of ATL patients.

RESULTS

Serum Kyn concentrations and Kyn/Trp ratios were significantly higher in HTLV-1 ACs than healthy controls. Both increased significantly with progression from HTLV-1 AC to ATL. However, there were no significant differences in the serum Trp concentrations between ATL patients, HTLV-1 ACs, and controls. IDO was possibly produced by ATL and/or cells of the microenvironment. Multivariate analyses demonstrated that a high serum Kyn/Trp ratio and high Kyn level, but not a high Trp level, were significantly independent detrimental prognostic factors in ATL, as well as in that subset of patients with aggressive variant ATL.

CONCLUSIONS

Quantification of serum Kyn and Trp is useful for predicting prognosis of an individual ATL patient. Furthermore, ATL, especially in patients with a high serum Kyn/Trp ratio, is an appropriate disease for testing novel cancer immunotherapies targeting IDO.

Current Approaches in the Treatment of Relapsed and Refractory Acute Myeloid Leukemia

The limited sensitivity of the historical treatment response criteria for acute myeloid leukemia (AML) has resulted in a different paradigm for treatment compared with most other cancers presenting with widely disseminated disease. Initial cytotoxic induction chemotherapy is often able to reduce tumor burden to a level sufficient to meet the current criteria for "complete" remission. Nevertheless, most AML patients ultimately die from their disease, most commonly as clinically evident relapsed AML. Despite a variety of available salvage therapy options, prognosis in patients with relapsed or refractory AML is generally poor. In this review, we outline the commonly utilized salvage cytotoxic therapy interventions and then highlight novel investigational efforts currently in clinical trials using both pathway-targeted agents and immunotherapy based approaches. We conclude that there is no current standard of care for adult relapsed or refractory AML other than offering referral to an appropriate clinical trial.

Recent advances in the treatment of adult T-cell leukemia-lymphomas

Recent advances in treatment for adult T-cell leukemia-lymphoma (ATL) are reviewed herein. It is currently possible to select a therapeutic strategy for ATL and predict prognosis by classification of patients by clinical subtypes and clinicopathological factors. Although the overall survival (OS) of patients with ATL has increased marginally because of advances in chemotherapy, further prolongation of survival might be difficult with conventional chemotherapy alone. Promising results have been reported for antiviral therapy using zidovudine and interferon-α, and, indeed, antiviral therapy is currently the standard treatment for patients with ATL in western countries. Remarkably, the 5-year OS rates are 100% for both the smoldering-type and chronic-type ATL. Recently, treatments for ATL have included allogeneic hematopoietic stem cell transplantation and molecular targeted therapies. Furthermore, the anti-CCR4 monoclonal antibody mogamulizumab has been shown to have marked cytotoxic effects on ATL cells, especially in the leukemic type of ATL. In the lymphoma type of ATL, the response rate may be improved by combining mogamulizumab with chemotherapy. It should be recognized that prevention of infection from carriers of human T-cell leukemia virus type-I and transfer of the virus from mother to infant are crucial issues for the eradication of ATL.

Treatment of peripheral T-cell lymphoma: are we data driven or driving the data?

Peripheral T-cell lymphomas (PTCL) are a group of uncommon and heterogeneous malignancies arising from a postthymic or mature T-lymphocyte. The treatment of PTCL remains a challenging endeavor. Compared with the more common aggressive B-cell lymphomas, more patients with PTCL will be refractory to initial therapy and those who achieve responses often will have shorter progression-free survival. Despite retrospective data that suggest that anthracycline-based multiagent chemotherapy regimens may not provide a benefit compared with nonanthracycline regimens, nonanthracycline-based regimens, with the notable exception of L-asparaginase regimens for extranodal NK/T-cell lymphoma, have been disappointing so far. Based on phase II evidence and subset analyses available, we believe that the addition of etoposide to standard regimens and consolidation of first remissions with autologous stem cell transplantation (autoSCT) provides the best outcome in patients with PTCL and currently use CHOEP followed by ASCT for eligible patients with the common PTCL subtype: PTCL-NOS, AITL, and ALK negative ALCL. For those with ALK-positive ALCL standard CHOP or CHOEP is appropriate with consideration of ASCT only for those with high-risk disease. Other strategies to incorporate additional agents, such as with dose-adjusted EPOCH or sequential CHOP-ICE regimens are logical options; however, they lack the supporting literature of CHOEP. Whereas the above recommendation is our current off-protocol approach, with the possible exception of low risk ALK positive ALCL, none of these choices is supported by strong enough data to supplant a well-conceived clinical trial as the truly preferred strategy in PTCL. The novel agents, romidepsin, pralatrexate, and brentuximab vedotin, are currently approved in the relapsed/refractory setting. These agents are being studied as additions or substitutions for other agents in up-front multiagent chemotherapy regimens. In the relapsed/refractory setting, both pralatrexate and romidepsin remain well-studied choices with some patients achieving a response with durability. Clinical trials of new agents in PTCL continue to be a valuable option and an important part of routine patient management as progressive disease often is seen. Lastly, we believe patients with relapsed/refractory PTCL should be considered for allogeneic stem cell transplantation if a suitable response is demonstrated and a willing donor is available.

Management of relapses after hematopoietic cell transplantation in T-cell non-Hodgkin lymphomas

T-cell non-Hodgkin lymphomas (NHLs) are a heterogeneous group of malignancies that represent 10%-15% of all NHLs. The prognosis of relapsed T-cell NHL is poor, especially for those relapsing after an autologous (auto-) or allogeneic (allo-) hematopoietic cell transplantation (HCT). Disease relapse post auto-HCT is best managed on a clinical trial. In the absence of an investigational protocol, the choice of salvage therapies should take into account patient performance status, eligibility for an allo-HCT, and surface CD30 expression. CD30-directed therapies or aggressive salvage regimens can be used as a bridge to allo-HCT in medically fit patients. In the elderly or more infirm patients, single-agent therapies could be offered, aiming at palliation. Similarly, relapse after an allo-HCT is not uncommon and is a real challenge. Reduction in ongoing immune suppression or donor lymphocyte infusion are often considered in this setting to augment graft-versus-lymphoma (GVL) effects and can occasionally provide durable disease control. Clinical trials designed to investigate novel therapeutic agents with immunomodulatory properties to augment GVL effects (eg, histone deacetylase [HDAC] inhibitors, proteasome inhibitor, lenalidomide) or targeted therapies (eg, aurora A kinase inhibitors, anaplastic lymphoma kinase [ALK] inhibitors) are sorely needed to improve the dismal outcomes of T-cell NHL relapsing after an allo-HCT.

Distinct clinical features of infectious complications in adult T cell leukemia/lymphoma patients after allogeneic hematopoietic stem cell transplantation: a retrospective analysis in the Nagasaki transplant group

Although allogeneic hematopoietic stem cell transplantation (allo-SCT) is performed as a curative option in adult T cell leukemia-lymphoma (ATL) patients, its high transplantation-related mortality raises a serious issue. The clinical features of infectious complications after transplantation are not well known. To analyze the impact of infections after allo-SCT for ATL, we retrospectively compared infectious complications in 210 patients at 3 institutions in Nagasaki prefecture between 1997 and 2009. There were 91 patients with acute myeloid leukemia (AML), 51 with acute lymphoblastic leukemia/lymphoblastic lymphoma (ALL/LBL), and 68 with ATL. No patient received ganciclovir or foscarvir as prophylaxis, and most patients received antifungal prophylaxis with fluconazole or itraconazole. The cumulative incidence of cytomegalovirus (CMV) infection at 3 years was 69.2% in ATL patients versus 54.4% in AML patients (P = .0255). Cumulative infection-related mortality was significantly higher in ATL patients than in the 2 other groups (ATL versus AML, P = .0496; ATL versus ALL/LBL, P = .0075), and most death-causing pathogens were bacteria and fungus. The appearance of CMV infection was negatively associated with infectious mortality in ATL patients, but the P value for this association was near the borderline of significance (P = .0569). In multivariate analysis, transplantation using unrelated bone marrow and episodes of CMV infection were associated with worse overall survival in ATL patients, but were not in either AML or ALL/LBL patients. Collectively, the impact of infectious complications after transplantation in ATL patients was different from that in AML and ALL/LBL patients, suggesting that a more intensive strategy for infection control in ATL patients is required to reduce infectious mortality.