Allogeneic transplantation for adult T-cell leukemia/lymphoma in adolescent and young adults and young patients: A nationwide retrospective study by the ATL working group of the Japan society for transplantation and cellular therapy.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) provides durable remission for patients with adult T-cell leukemia/lymphoma (ATL); however, few studies have focused on post-transplant outcomes in ATL patients ≤49 years. To clarify prognostic factors in ATL among patients <40 years (adolescents and young adult [AYA]; n = 73) and 40-49 years (Young; n = 330), we conducted a nationwide retrospective study. Estimated 3-year overall survival (OS) rates were 61.8% and 43.1% in AYA and Young patients, respectively (p = 0.005). In the multivariate analysis, Young patients showed worse OS (Hazard ratio (HR) [95% confidential interval] 1.62 [1.10-2.39], p = 0.015), chronic graft-versus-host disease (GVHD)-free and relapse-free survival (CRFS) (HR 1.54 [1.10-2.14], p = 0.011), and GVHD-free and relapse-free survival (GRFS) (HR 1.40 [1.04-1.88], p = 0.026) than AYA patients. No significant differences were observed in OS, CRFS, or GRFS between the myeloablative conditioning (MAC) and reduced-intensity conditioning (RIC) regimens; however, non-relapse mortality was significantly lower in patients with the RIC regimen than those with the MAC regimen (HR 0.46 [0.24-0.86], p = 0.015). In summary, OS was worse in Young patients than in AYA patients in the allo-HSCT setting for ATL. Furthermore, the RIC regimen has potential as an alternative treatment option for ATL patients ≤49 years.

Superior Survival After Unrelated Allogeneic Stem Cell Transplantation With Low-Dose ATG Compared to Low-Dose TBI in Myeloablative Fludarabine/Busulfan-Based Regimen for MDS on Behalf of the Adult MDS Working Group of the JSTCT.

The fludarabine/intravenous busulfan 12.8 mg/kg (FB4) regimen is an effective conditioning regimen in allogeneic hematopoietic stem cell transplantation for myelodysplastic syndrome (MDS); however, limited data is available on the prognostic impact of FB4 with low-dose anti-thymoglobulin (ATG ≤ 5 mg/kg) or low-dose total body irradiation (TBI ≤ 4 Gy). Therefore, we retrospectively evaluated the outcomes in 280 adults with de novo MDS who underwent their first transplantation from an unrelated donor between 2009 and 2018. Median age was 61 yr (range, 16 to 70 yr). In the FB4 alone (FB4), FB4 plus ATG (FB4-ATG), and FB4 plus TBI (FB4-TBI) groups, 3-yr overall survival (OS) rates were 39.9%, 64.8%, and 43.7%; 3-yr nonrelapse mortality (NRM) were 32.1%, 22.1%, and 27.1%; and 3-yr relapse incidences were 34.7%, 21.2%, and 28.9%, respectively. The multivariate analyses showed that FB4-ATG group significantly correlated with better OS (hazard Ratio [HR], 0.51; 95% confidence interval [CI], 0.27 to 0.95; P = .032) than FB4 group. FB4-ATG group tended to correlate with lower NRM (HR, 0.36; 95% CI, 0.13 to 1.06; P = .063) than FB4 group. In comparison with FB4-TBI group, FB4-ATG group showed better OS (HR 0.52, 95% CI 0.27 to 0.99, P = .049) and NRM (HR 0.034, 95% CI 0.11 to 0.92, P = .034). No significant differences were observed in OS and NRM between the FB4-TBI and FB4 groups. The present study demonstrated that the FB4 plus low-dose ATG regimen improved OS and NRM, but FB4 plus low-dose TBI regimen had no clear benefit over FB4 alone, in MDS patients who used unrelated donors.

[Allogeneic transplantation as a therapeutic option for atypical chronic myeloid leukemia].

Atypical chronic myeloid leukemia (aCML) is a rare disease classified as a myelodysplastic/myeloproliferative neoplasm (MDS/MPN). Recent advances in gene mutational profiling have clarified the characteristics of aCML as a disease entity relative to other MDS/MPNs. Although some studies suggest the efficacy of DNA demethylating agents and tyrosine kinase inhibitors, data about these agents are limited due to the small number of patients. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is only therapeutic option that can provide durable remission for aCML and other MDS/MPNs. Retrospective studies from Europe and Japan revealed the clinical results of allo-HSCT for aCML. This review summarizes the pathogenesis of aCML and the development of allo-HSCT and other therapeutic options.

Improved survival among elderly patients with aggressive adult T-cell leukemia/lymphoma: Impact of mogamulizumab-containing chemotherapy.

Due to the poor prognosis of adult T-cell leukemia/lymphoma (ATL), new treatments are urgently needed, especially for elderly patients with aggressive ATL. The anti-CCR4 antibody drug mogamulizumab (MOG) has been approved for the treatment of untreated ATL. To analyze the impact of MOG on elderly patients, we conducted a retrospective analysis of patients aged 70 years and older with aggressive ATL diagnosed at our institution between 2015 and 2021. Among 32 patients, including those who received best supportive care, the median survival time (MST) and 2-year overall survival (OS) rate were 14.6 months (range, 0.0-83.7), and 34.7% [95% confidence interval (CI), 18.2-51.9], respectively, which were better than outcomes in our previous study. The MST and 2-year OS for patients treated with MOG-containing chemotherapy were 18.1 months (range, 4.0-83.7) and 45.0% (95%CI, 23.1-64.7), respectively, demonstrating clear improvement. Adverse events observed with MOG-containing treatment, such as myelosuppression and skin rash, were similar to those reported previously. Univariate analysis identified comorbidity as a predictor of poor outcomes, but not intensity of MOG-containing treatment, suggesting a different mechanism of action than that of classical chemotherapy. Our study suggests that MOG-containing treatments are an option for elderly patients with ATL.

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.

Septic arthritis as breakthrough invasive fusariosis after cord blood transplantation.

A 63-year-old male received a third allogeneic hematopoietic stem cell transplantation with voriconazole prophylaxis for relapsed acute myeloid leukemia. He developed septic arthritis without any typical skin lesions due to fungal infection on day 42. Treatment with liposomal amphotericin B was initiated following surgical debridement; however, he died of progressive fungal infection. Ribosomal DNA sequencing identified Fusarium solani species complex (FSSC) harboring voriconazole resistance. This clinical course indicates that breakthrough invasive fusariosis (azole-resistant FSSC infection) needs to be considered as a pathogen when patients with hematological malignancies develop septic arthritis without typical skin lesions during voriconazole prophylaxis.

RUNX1 expression is regulated by a super-enhancer and is a therapeutic target in adult T-cell leukemia/lymphoma.

Super-enhancers (SEs) play an important role in regulating tumor-specific gene expression. JQ1, a Bromodomain-containing protein 4 (BRD4) inhibitor, exerts antitumor effects by disrupting SE-mediated regulation of gene expression. We investigated the anti-adult T-cell leukemia/lymphoma (ATL) effects of JQ1. JQ1 induced apoptosis and inhibited ATL cell proliferation. JQ1 suppressed RUNX1expression through the disruption of SE-mediated gene regulation. In the previous reports, it was shown that IC50s of AI-10-104 and Ro5-3335, RUNX1 inhibitors were 1-10 µM for lymphoblastic leukemia cell lines carrying RUNX1 mutations. In the present study, we demonstrated that IC50s of AI-10-104 and Ro5-3335 were also 1-10 µM or lower for ATL cell lines. Simultaneously, AI-10-104 suppressed MYC proto-oncogene (c-MYC) expression. RUNX1 is a potential therapeutic target for ATL that promotes c-MYC expression. We showed that RUNX1 expression is regulated via SEs in ATL and that RUNX1 may be a novel therapeutic target for ATL.

Individual HLAs affect survival after allogeneic stem cell transplantation in adult T-cell leukaemia/lymphoma.

Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is the only curative therapy for adult T-cell leukaemia/lymphoma (ATL). Specific HLAs are associated with outcomes of immunotherapy and allo-HSCT. We hypothesised that individual HLAs would affect the clinical outcomes of ATL patients after allo-HSCT. Using data from a Japanese registry, we retrospectively analysed 829 patients with ATL who received transplants from HLA-identical sibling donors or HLA-A, -B, -C or -DRB1 allele-matched unrelated donors between 1996 and 2015. We evaluated the overall mortality risk of HLA-A, -B and -DR antigens with frequencies exceeding 3%. Outcomes were compared between transplants with or without specific HLA antigens. Of the 25 HLAs, two candidates were identified but showed no statistically significant differences by multiple comparison. HLA-B62 was associated with a lower risk of mortality (hazard ratio [HR], 0.68; 95% confidence interval [CI]: 0.51-0.90; p = 0.008), whereas HLA-B60 was associated with a higher risk of mortality (HR, 1.64; 95% CI: 1.19-2.27; p = 0.003). In addition, HLA-B62 was associated with a lower risk of transplant-related mortality (TRM) (HR, 0.52; 95% CI: 0.32-0.85, p = 0.009), whereas HLA-B60 was associated with a higher risk of grades III-IV acute graft-versus-host disease (HR, 2.63; 95% CI: 1.62-4.27; p < 0.001). Neither HLA influenced relapse. The higher risk of acute GVHD in HLA-B60-positive patients and the lower risk of TRM in HLA-B62-positive patients were consistent with previously obtained results from patients with other haematological malignancies. Consideration of HLA in ATL patients may help to predict risk and outcomes after allo-HSCT.

Impact of Early Cytomegalovirus Reactivation After Allogeneic Hematopoietic Stem Cell Transplantation on Relapse in Patients With Myelodysplastic Syndrome: A Nationwide Retrospective Study From Adult Myelodysplastic Syndrome Working Group of the JSTCT.

Cytomegalovirus (CMV) reactivation is a prominent complication associated with adverse outcomes in allogeneic hematopoietic stem cell transplantation (HSCT). However, CMV reactivation after allogeneic HSCT may be associated with a lower incidence of relapse in some hematological malignancies. This study analyzed the Japanese registry data from 1082 patients with myelodysplastic syndrome (MDS) who underwent their first allogeneic HSCT and survived for 100 days after transplantation without graft failure or disease relapse to investigate this association. Patients who received cord blood transplants, demonstrated in vivo T cell depletion, underwent prophylactic anti-CMV treatment, or diagnosed with secondary MDS were excluded. CMV reactivation measured by pp65 antigenemia within 100 days after allogeneic HSCT was observed in 57.5% of patients, with a median time of 46 days from transplant. The 5-yr overall survival and cumulative incidence of relapse (CIR) in the cohort were 60.5% and 15.6%, respectively. The 5-yr CIR showed no significant difference between patients with and without CMV reactivation (14.4% versus 17.2%; P = .185). Interestingly, CMV reactivation within 100 days was significantly associated with a lower 5-yr CIR (7.6% versus 16.4%; P = .002) in patients with <5% myeloblasts in the bone marrow (BM) just before HSCT. Furthermore, this relevancy confirmed even when excluding patients with Grade II to IV acute GVHD (Hazard ratio: 0.38; 95% confidential intervals: 0.18-0.801; P = .011). Our findings indicate a correlation between early CMV reactivation and MDS relapse, based on the proportion of myeloblasts in the BM. These results may contribute to the development of effective CMV prophylaxis post-HSCT.

Prognostic impact of the conditioning intensity on outcomes after allogeneic transplantation for MDS with low blasts: a nationwide retrospective study by the adult MDS working group of the Japan Society for Transplantation and Cellular Therapy.

Poor prognostic factors, such as transfusion dependency and chromosomal risk, need to be considered in the indication of allogeneic hematopoietic cell transplantation (allo-HCT) for patients harboring myelodysplastic syndromes with less than 5% marrow blasts (MDS-Lo). We analyzed the post-transplant outcomes of 1229 MDS-Lo patients who received myeloablative (MAC)(n = 651), reduced-intensity (RIC)(n = 397), and non-myeloablative conditioning (NMAC) regimens (n = 181). The multivariate analysis revealed that the RIC group had better chronic graft-versus-host disease (GVHD)- and relapse-free survival (CRFS) (P = 0.021), and GVHD- and relapse-free survival (GRFS) than the MAC group (P = 0.001), while no significant differences were observed between the NMAC and MAC groups. In the subgroup analysis, the MAC group has better overall survival (P = 0.008) than the RIC group among patients with an HCT-comorbidity index (HCT-CI) score of 0, while the RIC group had better overall survival (P = 0.029) than the MAC group among those with an HCT-CI score ≥3. According to the type of conditioning regimen, total body irradiation 12 Gy-based MAC regimen showed better OS and CRFS than the other MAC regimen, and comparable outcomes to the RIC regimen. In conclusion, the RIC and NMAC regimens are promising options for MDS-Lo patients in addition to the MAC regimen.

Feasibility evaluation of a blood rotation system for efficient blood product utilization in remote island settings.

BACKGROUND AND OBJECTIVES: Geographical limitations in remote island medical facilities result in excessive wastage of blood products. To address this, we explored the feasibility of a novel blood rotation system, which enables the return and redelivery of blood products to/from the blood bank while ensuring the management of product quality, including temperature control. This study aimed to enhance the supply of blood products to these facilities. MATERIALS AND METHODS: The Japan Red Cross Nagasaki Blood Center, Nagasaki Goto Chuoh Hospital (NGCH) and Nagasaki University Hospital collaborated to coordinate the transport and supply of red blood cell (RBC) products. Type O, RhD-positive, irradiated RBC products were stored at a precise 4.0 ± 2.0°C in an active transport refrigerator (ATR). After transport from the Japan Red Cross Nagasaki Blood Center to NGCH, RBC products were held for 1 week in the ATR, and unused products were returned. Eligible returned products were reissued to the Nagasaki University Hospital. RESULTS: All the returned RBC products met the redelivery criteria. Among the 103 redelivered RBC preparations, 101 bags (98.1%) were successfully used. NGCH utilized 597 RBC products and discarded 80 samples. The ATR supplied 107 type O RBC bags without any wastage. The overall wastage rate was 10.2% during the study period compared with 24.2% in the same period in the previous year. CONCLUSION: This innovative supply and operation system ensures a consistent and secure RBC product supply to remote islands while maximizing blood product use.

Tyrosine phosphorylation of CARM1 promotes its enzymatic activity and alters its target specificity.

An important epigenetic component of tyrosine kinase signaling is the phosphorylation of histones, and epigenetic readers, writers, and erasers. Phosphorylation of protein arginine methyltransferases (PRMTs), have been shown to enhance and impair their enzymatic activity. In this study, we show that the hyperactivation of Janus kinase 2 (JAK2) by the V617F mutation phosphorylates tyrosine residues (Y149 and Y334) in coactivator-associated arginine methyltransferase 1 (CARM1), an important target in hematologic malignancies, increasing its methyltransferase activity and altering its target specificity. While non-phosphorylatable CARM1 methylates some established substrates (e.g. BAF155 and PABP1), only phospho-CARM1 methylates the RUNX1 transcription factor, on R223 and R319. Furthermore, cells expressing non-phosphorylatable CARM1 have impaired cell-cycle progression and increased apoptosis, compared to cells expressing phosphorylatable, wild-type CARM1, with reduced expression of genes associated with G2/M cell cycle progression and anti-apoptosis. The presence of the JAK2-V617F mutant kinase renders acute myeloid leukemia (AML) cells less sensitive to CARM1 inhibition, and we show that the dual targeting of JAK2 and CARM1 is more effective than monotherapy in AML cells expressing phospho-CARM1. Thus, the phosphorylation of CARM1 by hyperactivated JAK2 regulates its methyltransferase activity, helps select its substrates, and is required for the maximal proliferation of malignant myeloid cells.

Updated comparable efficacy of cord blood transplantation for chronic myelomonocytic leukaemia: a nationwide study.

Chronic myelomonocytic leukaemia (CMML) is a haematological malignancy with a poor prognosis. Allogeneic haematopoietic stem cell transplantation remains the only curative approach. Without human leucocyte antigen-matched related sibling donors, the optimal alternative donor has yet to be established. Although unrelated bone marrow transplantation (UBMT) has been extensively studied, cord blood transplantation (CBT) for CMML remains largely unexplored. This nationwide retrospective study compared the outcomes of UBMT and single-unit umbilical CBT in patients with CMML. This study included 118 patients who underwent their first allo-HSCT during 2013-2021. Of these, 50 received BMT (UBMT group), while 68 underwent CBT (CBT group). The primary endpoint was the 3-year overall survival (OS). There were comparable 3-year OS rates between the UBMT (51.0%, 95% confidence interval [CI]: 34.1-65.5%) and CBT (46.2%, 95% CI: 33.2-58.1%; P = 0.60) groups. In the inverse probability of treatment weighting analysis, CBT did not show significantly improved outcomes compared with UBMT regarding the 3-year OS rate (hazard ratio 0.97 [95% CI: 0.57-1.66], P = 0.91). Thus, CBT may serve as an alternative to UBMT for patients with CMML. Further research is necessary to optimise transplantation strategies and enhance outcomes in patients with CMML undergoing CBT.

Comparison of Melphalan Dose in Patients with Myelodysplastic Syndrome Undergoing Allogeneic Transplantation with Reduced-Intensity Conditioning.

The present study compared lower-dose melphalan (80 mg/m2, FM80) and higher-dose melphalan (140 mg/m2, FM140) when administering reduced-intensity conditioning with fludarabine in adult patients with myelodysplastic syndrome (MDS) undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). We retrospectively analyzed nationwide registry data (2006 to 2019) and compared transplant outcomes between the 2 groups. Ninety-two patients (median age, 61 [interquartile range, 56 to 65] years) were assigned to the FM80 and FM140 groups by propensity score matching. The 3-year overall survival (OS) rate in the FM140 group (63.9%; 95% confidence interval [CI], 52.9% to 73.0%) was significantly higher than that in the FM80 group (54.2%; 95% CI, 37.1% to 52.1%) (P = .038). The FM140 group had a nonsignificantly (P = .095) lower 3-year cumulative incidence of relapse (15.5%; 95% CI, 8.9% to 23.8% versus 26.0%; 95% CI, 17.3% to 35.5%). The 3-year cumulative incidences of nonrelapse mortality were 22.3% (95% CI, 14.1% to 31.8%) and 23.7% (95% CI, 15.4% to 33.2%) in the FM80 and FM140 groups, respectively (P = .49). The beneficial effect of FM140 was more evident in patients with a poor cytogenetic risk. Our findings suggest the superiority of FM140 in patients with MDS undergoing allo-HSCT, especially in high-risk patients.

The prognosis and risk factors for patients with complex karyotype myelodysplastic syndrome undergoing allogeneic haematopoietic stem cell transplantation.

Allogeneic haematopoietic stem cell transplantation (HCT) is the curative treatment for myelodysplastic syndrome with a complex karyotype (CK-MDS). However, only a few studies have been limited to patients with CK-MDS undergoing allogeneic HCT. This study aimed to identify the risk factors for patients with CK-MDS undergoing allogeneic HCT. We included 691 patients with CK-MDS who received their first allogeneic HCT. The overall survival (OS) was the primary end-point, estimated using the Kaplan-Meier method. Prognostic factors were identified using a Cox proportional hazards model. The 3-year OS was 29.8% (95% confidence interval [CI]: 26.3-33.3). In the multivariable analysis, older age (hazard ratio [HR]: 1.44, 95% CI: 1.11-1.88), male sex (HR: 1.38, 95% CI: 1.11-1.71), poor haematopoietic cell transplant comorbidity index (HR: 1.47, 95% CI: 1.20-1.81), red blood cell transfusion requirement (HR: 1.58, 95% CI: 1.13-2.20), platelet transfusion requirement (HR: 1.85, 95% CI: 1.46-2.35), not-complete remission (HR: 1.55, 95% CI: 1.16-2.06), a high number of karyotype abnormality (HR: 1.63, 95% CI: 1.18-2.25) and monosomal karyotype (HR: 1.49, 95% CI: 1.05-2.12) were significantly associated with OS. Thus, the 3-year OS of allogeneic HCT was 29.8% in patients with CK-MDS, and we identified risk factors associated with poor OS.

Single-unit unrelated cord blood transplantation versus HLA-matched sibling transplantation in adults with advanced myelodysplastic syndrome: A registry-based study from the adult MDS working group of the Japanese society for transplantation and cellular therapy.

Allogeneic hematopoietic stem cell transplantation (HCT) remains the only potential curative therapeutic modality for advanced myelodysplastic syndrome (MDS). Within HCT, the advancement of cord blood transplantation (CBT) procedures has resulted in a drastic expansion of CBT as a donor source for MDS. However, data comparing matched sibling donors (MSDs) HCT with CBT for advanced MDS, which was defined as refractory anemia with an excess of blasts (RAEB)-1 and RAEB-2 according to the World Health Organization classification at the time of HCT, have not been explored. We retrospectively compared survival and other posttransplant outcomes in 999 adult patients with advanced MDS after receiving allogeneic HCT in Japan between 2011 and 2020, using either MSD (n = 331) or single-unit unrelated cord blood (UCB) (n = 668). In the multivariate analysis, there were no significant differences in overall survival (hazard ratio [HR], 1.10; 95% confidence interval [CI], 0.90-1.34; P = 0.347), disease-free survival (HR, 1.01; 95% CI, 0.84-1.23; P = 0.845), relapse (HR, 0.88; 95% CI, 0.68-1.15; P = 0.370), or non-relapse mortality (HR, 1.15; 95% CI, 0.87-1.50; P = 0.310) between MSD recipients and UCB recipients. UCB was significantly associated with lower neutrophil (HR, 0.28; 95% CI, 0.24-0.33; P < 0.001) and lower platelet (HR, 0.29; 95% CI, 0.23-0.36; P < 0.001) recovery compared to MSD. UCB was significantly associated with a lower incidence of chronic graft-versus-host disease (GVHD) (HR, 0.57; 95% CI, 0.44-0.75; P < 0.001) and extensive chronic GVHD (HR, 0.46; 95% CI, 0.32-0.67; P < 0.001) compared to MSD. Similar results were observed after adjusting for differences between MSD and UCB recipients by propensity score matching analysis. Our study demonstrated that single CBT and MSD HCT had similar survival outcomes for adult patients with advanced MDS despite the lower hematopoietic recovery in CBT recipients and higher chronic GVHD in MSD recipients.

HLA-Haploidentical Peripheral Blood Stem Cell Transplantation with Post-Transplantation Cyclophosphamide versus HLA-Matched Unrelated Donor Transplantation for Myelodysplastic Syndrome.

Allogeneic hematopoietic cell transplantation (allo-HCT) is the sole curative therapy for myelodysplastic syndrome (MDS). In the absence of an HLA-matched sibling donor, an HLA-matched unrelated donor (MUD) is considered the leading candidate. However, in recent decades, the alternative donor pool has been extended to HLA-haploidentical donors, especially with the development of graft-versus-host disease (GVHD) prophylaxis using post-transplantation cyclophosphamide (PTCy). Comparative data for haploidentical and MUD allo-HCT in patients with MDS are scarce. We retrospectively analyzed 697 adult patients with MDS who underwent HLA-haploidentical peripheral blood stem cell transplantation (haplo-PBSCT) with PTCy (n = 136), MUD bone marrow transplantation (MUD-BMT) (n = 465), or MUD peripheral blood stem cell transplantation (MUD-PBSCT) (n = 96) as their first allo-HCT between 2014 and 2020 using Japanese registry data. Multivariable analyses demonstrated faster neutrophil engraftment (hazard ratio [HR], 2.19; 95% confidence interval [CI], 1.65 to 2.90; P < .001) and platelet engraftment (HR, 2.31; 95% CI, 1.72 to 3.10; P < 0001) in the MUD-PBSCT cohort compared with the haplo-PBSCT cohort. MUD-BMT was associated with a higher incidence of grade II-IV acute GVHD than haplo-PBSCT (HR, 1.52; 95% CI, 1.00 to 2.29; P = .048). Among patients without in vivo T cell depletion using antithymocyte globulin (ATG) (haplo-PBSCT, n = 136; MUD-BMT, n = 446; MUD-PBSCT, n = 65), MUD-PBSCT recipients experienced faster hematopoietic recovery, MUD-BMT recipients (HR, 1.54; 95% CI, 1.02 to 2.32; P = .042) or MUD-PBSCT recipients (HR, 1.83; 95% CI, 1.06 to 3.18; P = .03) had a higher incidence of grade II-IV acute GVHD, and MUD-PBSCT recipients developed chronic GVHD more frequently than haplo-PBSCT recipients (HR, 1.74; 95% CI, 1.04 to 2.89; P = .034). There were no significant differences in overall survival, disease-free survival, GVHD-free relapse-free survival, relapse, or nonrelapse mortality in the haplo-PBSCT cohort versus the MUD-BMT or MUD-PBSCT cohorts. In conclusion, despite differences in the incidences of hematopoietic engraftment and GVHD depending on graft type and ATG use in MUD transplant recipients, major transplantation outcomes were comparable between recipients of haplo-PBSCT using PTCy and recipients of MUD-BMT or MUD-PBSCT.

Should a matched sibling donor still be considered the primary option for allogeneic hematopoietic cell transplantation in patients over 50 years of age with myelodysplastic syndrome?

Human leukocyte antigen (HLA)-matched sibling donors (MSDs) are the preferred choice for allogeneic hematopoietic cell transplantation (HCT). However, as myelodysplastic syndrome (MDS) is most frequently diagnosed in the elderly, MSDs are also likely to be of advanced age. It is unclear whether an MSD should be considered the primary choice for allogeneic HCT in elderly patients with MDS. We retrospectively compared survival and other outcomes in 1787 patients with MDS over 50 years of age and receiving allogeneic HCT between 2014 and 2020, using either MSD (n = 214), 8/8 allele-matched unrelated donor (MUD) (n = 562), 7/8 allele-MUD (n = 334), or unrelated cord blood (UCB) (n = 677) in Japan. In multivariate analysis, compared to MSD transplants, the risk of relapse was significantly lower following 8/8MUD transplants (hazard ratio [HR], 0.74; P = 0.047), whereas non-relapse mortality was significantly higher following UCB transplants (HR, 1.43; P = 0.041). However, donor type did not determine overall survival, disease-free survival, or graft-versus-host disease (GVHD)-free, relapse-free survival, but chronic GVHD-free, relapse-free survival was better after UCB (HR, 0.80; P = 0.025) and 8/8MUD (HR, 0.81; P = 0.032) compared to MSD transplants. Our study demonstrated that MSDs are not superior to alternative HCT methods, such as 8/8MUD, 7/8MUD, or UCB, in this population.