Long-Term Outcome after Bone Marrow Transplantation for Aplastic Anemia Using Cyclophosphamide and Total Lymphoid Irradiation as Conditioning Regimen

AbstractWe retrospectively studied 49 patients in a single institute to evaluate the long-term outcome of total lymphoid irradiation (TLI) conditioning for allogeneic stem cell transplantation (allo-SCT) to treat aplastic anemia (AA). Most of the patients had received transfusions and had undergone previous treatment, with 33 receiving related transplants and 16 receiving unrelated transplants. Conditioning consisted of cyclophosphamide (Cy; 200 mg/kg) plus TLI (750 cGy) for related transplantation and Cy plus total body irradiation (TBI; 500 cGy) and TLI (500 cGy) for unrelated transplantation. Antithymocyte globulin (ATG) was added for 6 of the unrelated transplantations. Graft-versus-host-disease (GVHD) prophylaxis consisted mainly of cyclosporine (CSA) and methotrexate (MTX). Graft failure developed in 2 patients (4.1%). With a median follow-up of 7 years, overall survival (OS) was 81% and was not statistically significantly different between the patients receiving related transplants and those receiving unrelated transplants. In multivariate analyses, a history of previous treatment with ATG was the sole factor associated with a worse survival rate, and the interval from diagnosis to treatment was not prognostic. The incidence of acute (grade II to IV) GVHD (aGVHD) was 23%, and that of chronic GVHD (cGVHD) was 29%. Female-to-male transplantation was the sole factor associated with chronic GVHD. B cell lymphoproliferative disorder developed only after the ATG-containing conditioning. No other secondary malignancies developed after long-term follow-up. Our findings suggest that TLI conditioning is feasible and effective for patients with AA

Outcome of Allogeneic Hematopoietic Stem Cell Transplantation for Acute Myeloid Leukemia Patients with Central Nervous System Involvement

AbstractCentral nervous system (CNS) involvement in adult acute myeloid leukemia (AML) is rare and associated with poor outcomes. Therefore, CNS involvement in AML is an indicator for allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the impact of CNS involvement in AML on the outcome of allo-HSCT remains unclear. We performed a large-scale nationwide retrospective analysis to elucidate the outcomes of allo-HSCT on AML with CNS involvement (CNS+AML). Clinical data were collected from a registry database of the Japan Society for Hematopoietic Cell Transplantation. CNS involvement was defined as the infiltration of leukemia cells into the CNS or myeloid sarcoma in the CNS identified at any time from diagnosis to transplantation. One hundred fifty-seven patients with CNS+AML underwent allo-HSCT between 2006 and 2011. The estimated overall survival, cumulative incidence of relapse and nonrelapse mortality at 2 years for CNS+AML (51.2%, 30.2%, and 14.5%, respectively) were comparable with those for AML without CNS involvement (48.6%, 27.4%, and 22.0%, respectively). Univariate and multivariate analyses indicated that the development of chronic graft-versus-host disease, disease status, and cytogenetic risk category were independent prognostic factors for overall survival for CNS+AML. These results suggest that allo-HSCT may improve outcomes in patients with CNS+AML

Regulatory T Cell as a Biomarker of Treatment-Free Remission in Patients with Chronic Myeloid Leukemia

Simple Summary Tyrosine kinase inhibitors (TKIs) have dramatically improved the treatment of chronic myeloid leukemia (CML). Recently, TKIs were discontinued in patients with CML with deep molecular remission, and some patients have been reported to be able to maintain long-term treatment-free remission (TFR). However, there is no certainty regarding which patients can maintain TFR. We focused on immunity in the TFR phase and investigated the immunological mechanism of continuous TFR or recurrence. Our results suggest that the group that maintains the TFR is immunologically activated. In addition, regulatory T cells can be used as a biomarker. These results may have important implications for future strategies for maintaining TFR in CML treatment. Treatment-free remission (TFR) has become a therapeutic goal in chronic myeloid leukemia (CML), and approximately half of the patients with chronic phase-CML (CML-CP) with deep molecular remission (DMR) by tyrosine-kinase inhibitors (TKIs) have achieved TFR. However, the mechanism of continuous TFR is still unclear, as there are fluctuate patients who have BCR-ABL-positive leukemia cells but do not observe obvious relapse. We focused on the immune response and conducted an immune analysis using clinical samples from the imatinib discontinuation study, JALSG-STIM213. The results showed that, in the group that maintained TFR for 3 years, changes in regulatory T (Treg) cells were observed early after stopping imatinib treatment. The effector Treg (eTreg) cells increased transiently at 1 month after stopping imatinib and then returned to baseline at 3 months after stopping imatinib treatment. There was no difference in the Treg phenotype, and CD8(+) T cells in the TFR group were relatively activated. High concentrations of imatinib before stopping were negatively correlated with eTreg cells after stopping imatinib. These data suggest immunological involvement in the maintenance of the TFR, and that Treg cells after stopping imatinib might be a biomarker for TFR. Furthermore, high imatinib exposure may have a negative immunological impact on the continuous TFR

Peripheral Blood as a Preferable Source of Stem Cells for Salvage Transplantation in Patients with Graft Failure after Cord Blood Transplantation: A Retrospective Analysis of the Registry Data of the Japanese Society for Hematopoietic Cell Transplantation

To compare the different stem cell sources used in salvage transplantation for graft failure (GF) after cord blood transplantation (CBT), we retrospectively analyzed data of 220 patients who developed GF after undergoing CBT between January 2001 and December 2007 and underwent a second hematopoietic stem cell transplantation (HSCT) within 3 months. The donor sources for salvage HSCT were cord blood (n = 180), peripheral blood stem cells (PBSCs; n = 24), and bone marrow (BM; n = 16). The cumulative incidence of neutrophil engraftment on day 30 after the second HSCT was 39% with CB, 71% with PBSCs, and 75% with BM. Multivariate analysis revealed that PBSC and BM grafts were associated with a significantly higher engraftment rate than CB (hazard ratio [HR], 7.77; P < .001 and HR, 2.81; P = .016, respectively). Although the incidence of grade II-IV acute graft-versus-host disease was significantly higher in the PBSC group than in the CB group (HR, 2.83; P = .011), the incidence of 1-year nonrelapse mortality was lower in the PBSC group than in the CB group (HR, 0.43; P = .019), and 1-year overall survival was superior in the PBSC group compared with the CB group (HR, 0.45; P = .036). Our results suggest that PBSC is the preferable source of stem cells in salvage HSCT for GF after CBT

Overcoming minimal residual disease using intensified conditioning with medium-dose etoposide, cyclophosphamide and total body irradiation in allogeneic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia in adults

BACKGROUND AIMS: An intensified conditioning regimen incorporating medium-dose etoposide (VP16) is an option for patients with acute lymphoblastic leukemia (ALL). However, the prognostic impacts of the addition of VP16 to cyclophosphamide (CY) and total body irradiation (TBI) in patients with Philadelphia chromosome-positive (Ph+) ALL with regard to minimal residual disease (MRD) status have not been elucidated. METHODS: The authors retrospectively compared the outcomes of patients with Ph+ ALL who underwent allogeneic transplantation following VP16/CY/TBI (n = 101) and CY/TBI (n = 563). RESULTS: At 4 years, the VP16/CY/TBI group exhibited significantly better disease-free survival (DFS) (72.6% versus 61.7%, P = 0.027) and relapse rate (11.5% versus 21.1%, P = 0.020) and similar non-relapse mortality (16.0% versus 17.2%, P = 0.70). In subgroup analyses, the beneficial effects of the addition of VP16 on DFS were more evident in patients with positive MRD status (71.2% versus 48.4% at 4 years, P = 0.022) than those with negative MRD status (72.8% versus 66.7% at 4 years, P = 0.24). Although MRD positivity was significantly associated with worse DFS in patients who received CY/TBI (48.4% versus 66.7%, P < 0.001), this was not the case in those who received VP16/CY/TBI (71.2% versus 72.8%, P = 0.86). CONCLUSIONS: This study demonstrated the benefits of the addition of VP16 in Ph+ ALL patients, especially those with positive MRD status. VP16/CY/TBI could be a potential strategy to overcome the survival risk of MRD positivity

Personalized prediction of overall survival in patients with AML in non‐complete remission undergoing allo‐HCT

Allogenic hematopoietic stem cell transplantation (allo-HCT) is the standard treatment for acute myeloid leukemia (AML) in non-complete remission (non-CR); however, the prognosis is inconsistent. This study aimed to develop and validate nomograms and a web application to predict the overall survival (OS) of patients with non-CR AML undergoing allo-HCT (cord blood transplantation [CBT], bone marrow transplantation [BMT], and peripheral blood stem cell transplantation [PBSCT]). Data from 3052 patients were analyzed to construct and validate the prognostic models. The common significant prognostic factors among patients undergoing allo-HCT were age, performance status, percentage of peripheral blasts, cytogenetic risk, chemotherapy response, and number of transplantations. The conditioning regimen was a significant prognostic factor only in patients undergoing CBT. Compared with cyclophosphamide/total body irradiation, a conditioning regimen of ≥3 drugs, including fludarabine, with CBT exhibited the lowest hazard ratio for mortality (0.384; 95% CI, 0.266-0.554; p < 0.0001). A conditioning regimen of ≥3 drugs with CBT also showed the best leukemia-free survival among all conditioning regimens. Based on the results of the multivariable analysis, we developed prognostic models showing adequate calibration and discrimination (the c-indices for CBT, BMT, and PBSCT were 0.648, 0.600, and 0.658, respectively). Our prognostic models can help in assessing individual risks and designing future clinical studies. Furthermore, our study indicates the effectiveness of multi-drug conditioning regimens in patients undergoing CBT

Allogeneic hematopoietic stem cell transplantation for acute myeloid leukemia with t(6;9)(p23;q34) dramatically improves the patient prognosis: A matched-pair analysis

Acute myeloid leukemia (AML) with t(6;9)(p23;q34) is well known to have a poor prognosis treated with chemotherapy and autotransplantation. The presence of this karyotype is an indicator for allogeneic hematopoietic stem cell transplantation (HSCT); however, the impact of t(6;9)(p23;q34) on the HSCT outcome remains unclear. We conducted a matched-pair analysis of de novo AML patients with and without t(6;9)(p23;q34) using data obtained from the Japanese HSCT data registry. A total of 57 patients with t(6;9)(p23;q34) received transplants between 1996 and 2007, and 171 of 2056 normal karyotype patients matched for age, disease status at HSCT and graft source were selected. The overall survival, disease-free survival, cumulative incidence of relapse and the non-relapse mortality in t(6;9)(p23;q34) patients were comparable to those for normal karyotype patients. A univariate analysis showed that t(6;9)(p23;q34) had no significant impact on the overall survival. These findings suggest that allogeneic HSCT may overcome the unfavorable impact of t(6;9)(p23;q34) as an independent prognostic factor. © 2012 Macmillan Publishers Limited All rights reserved

Adult patients with Ph+ ALL benefit from conditioning regimen of medium‐dose VP16 plus CY/TBI

The medium-dose etoposide (VP16) added on cyclophosphamide (CY)/total body irradiation (TBI) is one of the intensified myeloablative conditioning regimens used in allogenic hematopoietic stem cell transplantation (allo-HSCT) for acute lymphoblastic leukemia (ALL). However, the patient subgroups who can actually benefit from VP16/CY/TBI compared to CY/TBI have not been precisely defined. Therefore, we conducted a multi-center retrospective study using the Japanese nationwide registry database to elucidate the efficacy of VP16/CY/TBI on post-transplant prognosis. Biological and clinical distinct subtypes (i.e., Philadelphia chromosome-positive (Ph+) and -negative (Ph−) ALL) were evaluated separately, which included 820 Ph+ and 1463 patients with Ph− ALL, respectively. Compared with the CY/TBI group, the VP16/CY/TBI group showed superior progression-free survival (PFS) in patients with Ph+ ALL (65% vs. 57% at 3 years after HSCT; adjusted hazard ratio (HR), 0.73; 95% confidence interval (CI), 0.55–0.98; p = 0.03), along with significantly reduced incidence of relapse (adjusted HR, 0.58; 95% CI, 0.37–0.90; p = 0.02) without the increase of non-relapse mortality (NRM). By contrast, in patients with Ph− ALL, VP16/CY/TBI did not improve PFS nor incidence of relapse; addition of VP16 reduced relapse (HR, 0.65; p = 0.06) in patients with Ph− ALL transplanted at CR1, while improved PFS was not observed (HR, 0.90; p = 0.52) due to increased NRM. This study demonstrated that VP16/CY/TBI is a more effective and well-tolerated regimen in comparison with CY/TBI in patients with myeloablative allo-HSCT for adult Ph+ ALL. Our findings can provide a novel algorithm for conditioning regimen selection in patients with adult ALL

Prognostic impact of complex and/or monosomal karyotypes in post‐transplant poor cytogenetic acute myeloid leukaemia: A quantitative approach

To evaluate the prognostic impact of complex karyotype (CK) and/or monosomal karyotype (MK) in combination with various clinical factors on allogeneic stem cell transplantation (HSCT) outcomes of patients with acute myeloid leukaemia (AML), we analysed the registry database of adult AML patients who underwent allogeneic HSCT between 2000 and 2019 in Japan. Among 16 094 patients, those with poor cytogenetic risk (N = 3345) showed poor overall survival (OS) after HSCT (25.3% at 5 years). Multivariate analyses revealed that CK and/or MK (hazard ratio [HR], 1.31 for CK without MK; 1.27 for MK without CK; and 1.73 for both), age at HSCT ≥50 years (HR, 1.58), male sex (HR, 1.40), performance status ≥2 (HR, 1.89), HCT-CI score ≥3 (HR, 1.23), non-remission status at HSCT (HR, 2.49), and time from diagnosis to HSCT ≥3 months (HR, 1.24) independently reduced post-HSCT OS among patients with poor cytogenetic risk AML. A risk scoring system based on the multivariate analysis successfully stratified patients into five distinct groups for OS. This study confirms the negative effects of CK and MK on post-HSCT outcomes, and offers a powerful risk scoring system for predicting prognoses after HSCT among AML patients with unfavourable cytogenetics