Allogeneic Stem Cell Transplantation in Refractory Acute Myeloid Leukaemia.

Refractory acute myeloid leukaemia is very difficult to treat and represents an unmet clinical need. In recent years, new drugs and combinations of drugs have been tested in this category, with encouraging results. However, all treated patients relapsed and died from the disease. The only curative option is allogeneic transplantation through a graft from a healthy donor immune system. Using myeloablative conditioning regimens, the median overall survival regimens is 19%. Several so-called sequential induction chemotherapies followed by allogeneic transplantation conditioned by reduced intensity regimens have been developed, improving the overall survival to 25-57%. In the allogeneic transplantation field, continuous improvements in practices, particularly regarding graft versus host disease prevention, infection prevention, and treatment, have allowed us to observe improvements in survival rates. This is true mainly for patients in complete remission before transplantation and less so for refractory patients. However, full myeloablative regimens are toxic and carry a high risk of treatment-related mortality. In this review, we describe the results obtained with the different modalities used in more recent retrospective and prospective studies. Based on these findings, we speculate how allogeneic stem cell transplantation could be modified to maximise its therapeutic effect on refractory acute myeloid leukaemia.

Neuromuscular electrical stimulation for physical function maintenance during hematopoietic stem cell transplantation: Study protocol.

Hematopoietic stem cell transplantation is a common life-saving treatment for hematologic malignancies, though can lead to long-term functional impairment, fatigue, muscle atrophy, with decreased quality of life. Although traditional exercise has helped reduce these effects, it is inconsistently recommended and infrequently maintained, and most patients remain sedentary during and after treatment. There is need for alternative rehabilitation strategies, like neuromuscular electrical stimulation, that may be more amenable to the capabilities of hematopoietic stem cell transplant recipients. Patients receiving autologous HCT are being enroled in a randomized controlled trial with 1:1 (neuromuscular electrical stimulation:sham) design stratified by diagnosis and sex. Physical function, body composition, quality of life, and fatigue are assessed prior to hematopoietic stem cell transplant (prior to initiating preparatory treatment) and 24±5 days post hematopoietic stem cell transplant (Follow-up 1); physical function and quality of life are also assessed 6-months post hematopoietic stem cell transplant (Follow-up 2). The primary outcome is between-group difference in the 6-minute walk test change scores (Follow-up 1-Pre-transplant; final enrolment goal N = 23/group). We hypothesize that 1) neuromuscular electrical stimulation will attenuate hematopoietic stem cell transplant-induced adverse effects on physical function, muscle mass, quality of life, and fatigue compared to sham at Follow-up 1, and 2) Pre-transplant physical function will significantly predict fatigue and quality of life at Follow-up 2. We will also describe feasibility and acceptability of neuromuscular electrical stimulation during hematopoietic stem cell transplant. This proposal will improve rehabilitative patient care and quality of life by determining efficacy and feasibility of a currently underutilized therapeutic strategy aimed at maintaining daily function and reducing the impact of a potent and widely used cancer treatment. This trial is registered with clinicaltrials.gov (NCT04364256).

Philadelphia chromosome-positive acute myeloid leukemia successfully treated by allogeneic hematopoietic stem cell transplantation: A case report and review of the literature.

RATIONAL: The Philadelphia chromosome (Ph) is seen in most patients with chronic myeloid leukemia and some patients with acute lymphoblastic leukemia. However, Ph-positive acute myeloid leukemia (Ph + AML) is a rare entity with a poor prognosis and a short median survival period. To date, there have been few clinical reports on this disease. And the treatment regimen of this disease has not been uniformly determined. PATIENT CONCERNS: We report a case of a Ph + AML. A 32-year-old male who was admitted to our hospital with weakness for 2 months. DIAGNOSIS: Philadelphia chromosome-positive acute myeloid leukemia. INTERVENTIONS: The patient achieved complete remission by the administration of a tyrosine kinase inhibitor, combined with low-intensity chemotherapy and a B-cell lymphoma 2 inhibitor. Then, allogeneic hematopoietic stem cell transplantation (allo-HSCT) from his sister was successfully performed. OUTCOMES: The patient has been in a continuous remission state for 6 months after transplantation. LESSONS: We reported a rare Ph + AML case, successfully treated with allo-HSCT. This case provided strong support for treating Ph + AML with allo-HSCT.

Brave new world: expanding home care in stem cell transplantation and advanced therapies with new technologies.

Hematopoietic stem cell transplantation and cell therapies like CAR-T are costly, complex therapeutic procedures. Outpatient models, including at-home transplantation, have been developed, resulting in similar survival results, reduced costs, and increased patient satisfaction. The complexity and safety of the process can be addressed with various emerging technologies (artificial intelligence, wearable sensors, point-of-care analytical devices, drones, virtual assistants) that allow continuous patient monitoring and improved decision-making processes. Patients, caregivers, and staff can also benefit from improved training with simulation or virtual reality. However, many technical, operational, and above all, ethical concerns need to be addressed. Finally, outpatient or at-home hematopoietic transplantation or CAR-T therapy creates a different, integrated operative system that must be planned, designed, and carefully adapted to the patient's characteristics and distance from the hospital. Patients, clinicians, and their clinical environments can benefit from technically improved at-home transplantation.

The rationale behind grafting haploidentical hematopoietic stem cells.

The ability to perform hematopoietic cell transplant across major histocompatibility complex barriers can dramatically increase the availability of donors and allow more patients across the world to pursue curative transplant procedures for underlying hematologic disorders. Early attempts at haploidentical transplantation using broadly reactive T-cell depletion approaches were compromised by graft rejection, graft-versus-host disease and prolonged immune deficiency. The evolution of haploidentical transplantation focused on expanding transplanted hematopoietic progenitors as well as using less broadly reactive T-cell depletion. Significant outcome improvements were identified with technology advances allowing selective depletion of donor allospecific T cells, initially ex-vivo with evolution to its current in-vivo approach with the infusion of the highly immunosuppressive chemotherapy agent, cyclophosphamide after transplantation procedure. Current approaches are facile and portable, allowing expansion of allogeneic hematopoietic cell transplantation for patients across the world, including previously underserved populations.

Comparison of upfront haploidentical hematopoietic stem cell transplantation and salvage haploidentical hematopoietic stem cell transplantation after immunosuppressive therapy in children with acquired severe aplastic anemia - a multicenter study.

Background: For children with severe aplastic anemia, if the first immunosuppressive therapy (IST) fails, it is not recommended to choose a second IST. Therefore, for patients without matched sibling donor (MSD) and matched unrelated donor (MUD), haploidentical hematopoietic stem cell transplantation (Haplo-HSCT) can be chosen as a salvage treatment. This article aims to explore the comparison between upfront Haplo-HSCT and salvage Haplo-HSCT after IST. Methods: 29 patients received salvage Haplo-HSCT, and 50 patients received upfront Haplo-HSCT. The two groups received Bu (Busulfan, 3.2mg/kg/d*2d on days -9 to-8), CY (Cyclophosphamide, 60mg/kg/d*2d on days -4 to-3), Flu (fludarabine, 40mg/m2/d*5d on days -9 to -5) and rabbit ATG (Anti-thymocyte globulin, total dose 10mg/kg divided into days -4 to -2). Results: The OS of the salvage Haplo-HSCT group showed no difference to the upfront Haplo-HSCT group (80.2 ± 8.0% vs. 88.7 ± 4.8%, p=0.37). The FFS of the salvage Haplo-HSCT group also showed no difference to the frontline Haplo-HSCT group (75 ± 8.2% vs. 84.9 ± 5.3%, p=0.27). There was no significant difference in the incidence of other complications after transplantation between the two groups, except for thrombotic microangiopathy (TMA). In the grouping analysis by graft source, the incidence of II-IV aGVHD in patients using PBSC ± BM+UCB was lower than that in the PBSC ± BM group (p=0.010). Conclusion: Upfront Haplo-HSCT and salvage Haplo-HSCT after IST in children with acquired severe aplastic anemia have similar survival outcomes. However, the risk of TMA increases after salvage Haplo-HSCT. This article provides some reference value for the treatment selection of patients. In addition, co-transplantation of umbilical cord blood may reduce the incidence of GVHD.

Personalized Timing for Allogeneic Stem-Cell Transplantation in Hematologic Neoplasms: A Target Trial Emulation Approach Using Multistate Modeling and Microsimulation.

PURPOSE: Decision about the optimal timing of a treatment procedure in patients with hematologic neoplasms is critical, especially for cellular therapies (most including allogeneic hematopoietic stem-cell transplantation [HSCT]). In the absence of evidence from randomized trials, real-world observational data become beneficial to study the effect of the treatment timing. In this study, a framework to estimate the expected outcome after an intervention in a time-to-event scenario is developed, with the aim of optimizing the timing in a personalized manner. METHODS: Retrospective real-world data are leveraged to emulate a target trial for treatment timing using multistate modeling and microsimulation. This case study focuses on myelodysplastic syndromes, serving as a prototype for rare cancers characterized by a heterogeneous clinical course and complex genomic background. A cohort of 7,118 patients treated according to conventional available treatments/evidence across Europe and United States is analyzed. The primary clinical objective is to determine the ideal timing for HSCT, the only curative option for these patients. RESULTS: This analysis enabled us to identify the most appropriate time frames for HSCT on the basis of each patient's unique profile, defined by a combination relevant patients' characteristics. CONCLUSION: The developed methodology offers a structured framework to address a relevant clinical issue in the field of hematology. It makes several valuable contributions: (1) novel insights into how to develop decision models to identify the most favorable HSCT timing, (2) evidence to inform clinical decisions in a real-world context, and (3) the incorporation of complex information into decision making. This framework can be applied to provide medical insights for clinical issues that cannot be adequately addressed through randomized clinical trials.

Macrophage depletion overcomes human hematopoietic cell engraftment failure in zebrafish embryo.

Zebrafish is widely adopted as a grafting model for studying human development and diseases. Current zebrafish xenotransplantations are performed using embryo recipients, as the adaptive immune system, responsible for host versus graft rejection, only reaches maturity at juvenile stage. However, transplanted primary human hematopoietic stem/progenitor cells (HSC) rapidly disappear even in zebrafish embryos, suggesting that another barrier to transplantation exists before the onset of adaptive immunity. Here, using a labelled macrophage zebrafish line, we demonstrated that engraftment of human HSC induces a massive recruitment of macrophages which rapidly phagocyte transplanted cells. Macrophages depletion, by chemical or pharmacological treatments, significantly improved the uptake and survival of transplanted cells, demonstrating the crucial implication of these innate immune cells for the successful engraftment of human cells in zebrafish. Beyond identifying the reasons for human hematopoietic cell engraftment failure, this work images the fate of human cells in real time over several days in macrophage-depleted zebrafish embryos.

[Efficacy of allogeneic hematopoietic stem cell transplantation based on a total body irradiation conditioning treatment regimen for adult acute lymphocytic leukemia].

Objective: To analyze the efficacy of allo-HSCT with total body irradiation (TBI) and chemotherapy alone in the treatment of adult ALL and to explore the factors affecting prognosis. Methods: The clinical data of 95 adult patients with ALL who underwent allo-HSCT from January 2015 to August 2022 were included. According to the conditioning regimen, the patients were divided into two groups: the TBI plus cyclophosphamide (TBI/Cy) group (n=53) and the busulfan plus cyclophosphamide (Bu/Cy) group (n=42). Hematopoietic reconstitution after transplantation, GVHD, transplantation-related complications, relapse rate (RR), non-relapse mortality (NRM), OS, and LFS were compared, and the factors related to prognosis were analyzed. Results: The median time of neutrophil engraftment was 14 (10-25) days in the TBI/Cy group and 14 (10-24) days in the Bu/Cy group (P=0.106). The median time of megakaryocyte engraftment was 17 (10-42) days in the TBI/Cy group and 19 (11-42) days in the Bu/Cy group (P=0.488). The incidence of grade Ⅱ-Ⅳ acute GVHD (aGVHD) in the TBI/Cy and Bu/Cy groups was 41.5% and 35.7%, respectively (P=0.565). The incidence of grade Ⅲ-Ⅳ aGVHD in these two groups was 24.5% and 4.8%, respectively (P=0.009). The incidence of severe chronic GVHD in the two groups was 16.7% and 13.5%, respectively (P=0.689). The incidence of cytomegalovirus infection, Epstein-Barr virus infection, severe infection, and hemorrhagic cystitis in the two groups was 41.5% and 35.7% (P=0.565), 34.0% and 35.7% (P=0.859), 43.4% and 33.3% (P=0.318), and 20.8% and 50.0% (P=0.003), respectively. The median follow-up time was 37.1 months and 53.3 months in the TBI/Cy and Bu/Cy groups, respectively. The 2-year cumulative RR was 17.0% in the TBI/Cy group and 42.9% in the Bu/Cy group (P=0.017). The 2-year cumulative NRM was 24.5% and 7.1%, respectively (P=0.120). The 2-year LFS was 58.5% and 50.0%, respectively (P=0.466). The 2-year OS rate was 69.8% and 64.3%, respectively (P=0.697). In the multivariate analysis, the conditioning regimen containing TBI was a protective factor for relapse after transplantation (HR=0.304, 95% CI 0.135-0.688, P=0.004), whereas the effect on NRM was not significant (HR=1.393, 95% CI 0.355-5.462, P=0.634). Infection was an independent risk factor for OS after allo-HSCT in adult patients with ALL. Conclusion: allo-HSCT based on TBI conditioning regimen had lower relapse rate and lower incidence of hemorrhagic cystitis for adult ALL, compared with chemotherapy regimen. While the incidence o grade Ⅲ/Ⅳ aGVHD was hgher in TBI conditioning regimen than that in chemotherapy regimen.

[Role and progress of allogeneic hematopoietic stem cell transplantation in the treatment of refractory/relapsed diffuse large B-cell lymphoma].

Diffuse large B-cell lymphoma (DLBCL) is the most common type of non Hodgkin's lymphoma. The current treatment plan can significantly improve the prognosis of patients, but about 30%-40% of DLBCL patients still experience drug resistance and relapse after treatment. For patients with refractory/relapse DLBCL, clinical treatment remains difficult and their prognosis is poor. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains one of the most important curative methods for refractory/relapse DLBCL patients. This article will review the role and progress of allo-HSCT in the treatment of refractory/relapse DLBCL.

Continuously improving outcome over time after second allogeneic stem cell transplantation in relapsed acute myeloid leukemia: an EBMT registry analysis of 1540 patients.

Second allogeneic stem cell transplantation (alloSCT2) is among the most effective treatments for acute myeloid leukemia (AML) relapse after first alloSCT (alloSCT1). Long-term EBMT registry data were used to provide large scale, up-to-date outcome results and to identify factors for improved outcome. Among 1540 recipients of alloSCT2, increasing age, better disease control and performance status before alloSCT2, more use of alternative donors and higher conditioning intensity represented important trends over time. Between the first (2000-2004) and last (2015-2019) period, two-year overall and leukemia-free survival (OS/LFS) increased considerably (OS: 22.5-35%, LFS: 14.5-24.5%). Cumulative relapse incidence (RI) decreased from 64% to 50.7%, whereas graft-versus-host disease and non-relapse mortality (NRM) remained unchanged. In multivariable analysis, later period of alloSCT2 was associated with improved OS/LFS (HR = 0.47/0.53) and reduced RI (HR = 0.44). Beyond, remission duration, disease stage and patient performance score were factors for OS, LFS, RI, and NRM. Myeloablative conditioning for alloSCT2 decreased RI without increasing NRM, leading to improved OS/LFS. Haploidentical or unrelated donors and older age were associated with higher NRM and inferior OS. In summary, outcome after alloSCT2 has continuously improved over the last two decades despite increasing patient age. The identified factors provide clues for the optimized implementation of alloSCT2.

Leveraging machine learning for predicting acute graft-versus-host disease grades in allogeneic hematopoietic cell transplantation for T-cell prolymphocytic leukaemia.

Orphan diseases, exemplified by T-cell prolymphocytic leukemia, present inherent challenges due to limited data availability and complexities in effective care. This study delves into harnessing the potential of machine learning to enhance care strategies for orphan diseases, specifically focusing on allogeneic hematopoietic cell transplantation (allo-HCT) in T-cell prolymphocytic leukemia. The investigation evaluates how varying numbers of variables impact model performance, considering the rarity of the disease. Utilizing data from the Center for International Blood and Marrow Transplant Research, the study scrutinizes outcomes following allo-HCT for T-cell prolymphocytic leukemia. Diverse machine learning models were developed to forecast acute graft-versus-host disease (aGvHD) occurrence and its distinct grades post-allo-HCT. Assessment of model performance relied on balanced accuracy, F1 score, and ROC AUC metrics. The findings highlight the Linear Discriminant Analysis (LDA) classifier achieving the highest testing balanced accuracy of 0.58 in predicting aGvHD. However, challenges arose in its performance during multi-class classification tasks. While affirming the potential of machine learning in enhancing care for orphan diseases, the study underscores the impact of limited data and disease rarity on model performance.

Therapeutic Choices in Patients with Ph-Positive Chronic Myelogenous Leukemia In Mexico in the Era of Tyrosine Kinase Inhibitors: Stem Cell Transplantation or Tyrosine Kinase Inhibitors? Fifteen Years Later.

UNASSIGNED: Background: Chronic myelogenous leukemia is a neoplastic proliferation of the granulocytic series. In Mexico, chronic myelogenous leukemia accounts for approximately 10% of all leukemias. Tyrosine-kinase inhibitors are considered front-line therapy in high-income countries, whereas allogeneic hematopoietic stem cell transplantation is a recognized therapeutic approach, mainly in low- and middle-income countries. Objective: To analyze the overall survival of persons with chronic myelogenous leukemia who have received tyrosine-kinase inhibitors or allogeneic hematopoietic stem cell transplantation in a medical center, since 1994, and briefly discuss the current indications of these treatments in the tyrosine-kinase inhibitors era. Methods: We retrospectively analyzed all patients with a diagnosis of chronic myelogenous leukemia treated in a medical center between 1994 and 2023; subsets of individuals who received an allogeneic hematopoietic stem cell transplantation or tyrosine-kinase inhibitors therapy as first-line treatment were analyzed. Results: 60 persons with chronic myelogenous leukemia were treated with allogeneic hematopoietic stem cell transplantation or tyrosine-kinase inhibitors: 35 received an allogeneic hematopoietic stem cell transplantation, whereas 25 were given tyrosine-kinase inhibitors. All patients who underwent an allogeneic hematopoietic stem cell transplantation engrafted successfully, and the procedure was completed on an outpatient basis in most cases (29/35). The median survival in allogeneic hematopoietic stem cell transplantation was 78.3 months (CI 95%: 0-205.6) and in persons given tyrosine-kinase inhibitors the median was not reached. Conclusion: Tyrosine-kinase inhibitors were significantly superior to allogeneic hematopoietic stem cell transplantation in prolonging the overall survival of persons with chronic myelogenous leukemia in our single institution experience. (Rev Invest Clin. 2024;76(2):91-6).

Graft failure after allogeneic hematopoietic stem cell transplantation in pediatric patients with acute leukemia: autologous reconstitution or second transplant?

BACKGROUND: Graft failure (GF) is a rare but serious complication after allogeneic hematopoietic stem cell transplantation (HSCT). Prevention of graft failure remains the most advisable approach as there is no clear recommendation for the best strategies for reversing this complication. Administration of growth factor, additional hematopoietic progenitor boost, or a salvage HSCT are current modalities recommended for the treatment of GF. Autologous recovery without evidence of disease relapse occurs rarely in patients with GF, and in the absence of autologous recovery, further salvage transplantation following a second conditioning regimen is a potential treatment option that offers the best chances of long-term disease-free survival. The preconditioning regimens of second HSCT have a significant impact on engraftment and outcome, however, currently there is no consensus on optimal conditioning regimen for second HSCT in patients who have developed GF. Furthermore, a second transplant from a different donor or the same donor is still a matter of debate. OBSERVATIONS: We present our experience in managing pediatric patients with acute leukemia who encountered graft failure following stem cell transplantation. CONCLUSIONS AND RELEVANCE: Although a second transplantation is almost the only salvage method, we illustrate that some pediatric patients with acute leukemia who experience graft failure after an allogeneic stem cell transplant using Myeloablative conditioning (MAC) regimen may achieve long-term disease-free survival through autologous hematopoiesis recovery.

Comparison of two autologous hematopoietic stem cell mobilization strategies in patients with multiple myeloma: CE plus G-CSF versus G-CSF only: A single-center retrospective analysis.

BACKGROUND: Despite recent advances in the treatment of multiple myeloma, high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (ASCT) remains an essential therapeutic keystone. As for the stem cell mobilization procedure, different regimens have been established, usually consisting of a cycle of chemotherapy followed by application of granulocyte-colony stimulating factor (G-CSF), although febrile neutropenia is a common complication. Following national guidelines, our institution decided to primarily use G-CSF only mobilization during the COVID-19 pandemic to minimize the patients' risk of infection and to reduce the burden on the health system. STUDY DESIGN AND METHODS: In this retrospective single-center analysis, the efficacy and safety of G-CSF only mobilization was evaluated and compared to a historic control cohort undergoing chemotherapy-based mobilization by cyclophosphamide and etoposide (CE) plus G-CSF. RESULTS: Although G-CSF only was associated with a higher need for plerixafor administration (p < .0001) and a higher number of apheresis sessions per patient (p = .0002), we were able to collect the target dose of hematopoietic stem cells in the majority of our patients. CE mobilization achieved higher hematopoietic stem cell yields (p = .0015) and shorter apheresis sessions (p < .0001) yet was accompanied by an increased risk of febrile neutropenia (p < .0001). There was no difference in engraftment after ASCT. DISCUSSION: G-CSF only mobilization is a useful option in selected patients with comorbidities and an increased risk of serious infections, especially in the wintertime or in future pandemics.

Minnelide suppresses GVHD and enhances survival while maintaining GVT responses.

Allogeneic hematopoietic stem cell transplantation (aHSCT) can cure patients with otherwise fatal leukemias and lymphomas. However, the benefits of aHSCT are limited by graft-versus-host disease (GVHD). Minnelide, a water-soluble analog of triptolide, has demonstrated potent antiinflammatory and antitumor activity in several preclinical models and has proven both safe and efficacious in clinical trials for advanced gastrointestinal malignancies. Here, we tested the effectiveness of Minnelide in preventing acute GVHD as compared with posttransplant cyclophosphamide (PTCy). Strikingly, we found Minnelide improved survival, weight loss, and clinical scores in an MHC-mismatched model of aHSCT. These benefits were also apparent in minor MHC-matched aHSCT and xenogeneic HSCT models. Minnelide was comparable to PTCy in terms of survival, GVHD clinical score, and colonic length. Notably, in addition to decreased donor T cell infiltration early after aHSCT, several regulatory cell populations, including Tregs, ILC2s, and myeloid-derived stem cells in the colon were increased, which together may account for Minnelide's GVHD suppression after aHSCT. Importantly, Minnelide's GVHD prevention was accompanied by preservation of graft-versus-tumor activity. As Minnelide possesses anti-acute myeloid leukemia (anti-AML) activity and is being applied in clinical trials, together with the present findings, we conclude that this compound might provide a new approach for patients with AML undergoing aHSCT.

Comparable outcomes of allogeneic peripheral blood versus bone marrow hematopoietic stem cell transplantation from a sibling donor for pediatric patients.

Traditionally, bone marrow (BM) has been preferred as a source of stem cells (SCs) in pediatric hematopoietic SC transplantation (HSCT); however, the use of peripheral blood SCs (PBSC) has recently increased. With advancing graft-versus-host disease (GVHD) prophylaxis, whether the BM is still a better SC source than PB in sibling donor HSCT remains controversial. Here, we compared the results of BM transplantation (BMT) and PBSC transplantation (PBSCT) in pediatric patients with malignant or non-malignant diseases receiving sibling HSCT using a total of 7.5 mg/kg of anti-thymocyte globulin (ATG). We retrospectively reviewed children who received HSCT from a sibling donor between 2005 and 2020 at Seoul National University Children's Hospital. Of the 86 patients, 40 underwent BMT, and 46 underwent PBSCT. Fifty- six patients had malignant diseases, whereas thirty patients had non-malignant diseases. All conditioning regimens comprised ATG. Busulfan-based myeloablative conditioning regimens were administered to patients with malignant diseases and approximately half of those with non-malignant diseases. The remaining half of the patients with non-malignant diseases were administered cyclophosphamide-based reduced- intensity conditioning regimens. According to studies conducted at our center, all BM donors received G-CSF before harvest to achieve early engraftment. In all 86 patients (47 males and 39 females), the median age at the time of HSCT was 11.4 (range, 0.7 - 24.6) years. The median follow-up period was 57.9 (range, 0.9-228.6) months, and the corresponding values for those with BM and PBSC were 77 (range, 2.4-228.6) months and 48.7 (range, 0.9-213.2) months, respectively. Engraftment failure occurred in one patient with BM and no patient with PBSC. The cumulative incidence of acute GVHD with grades II-IV was higher in PBSC (BM 2.5%, PBSC 26.1%, p = 0.002), but there was no significant difference in those with grades III-IV acute GVHD (BM 0%, PBSC 6.5%, p = 0.3703) and extensive chronic GVHD (BM 2.5%, PBSC 11.6%, p = 0.1004). There were no significant differences in treatment-related mortality (TRM) (BM 14.2%, PBSC 6.8%, p = 0.453), 5-year event-free survival (EFS) (BM 71.5%, PBSC 76.2%, p = 0.874), and overall survival (OS) rates (BM 80.8%, PBSC 80.3%, p = 0.867) between BM and PBSC in the univariate analysis. In the multivariate analysis, which included all factors with p < 0.50 in the univariate analysis, there was no significant prognostic factor for EFS or OS. There was no significant difference in the relapse incidence between BM and PBSC among patients with malignant diseases (BM 14.2%, PBSC 6.8%, p = 0.453). Additionally, there were no significant differences in the TRM, 5-year EFS, and OS rates between malignant and non-malignant diseases nor between the busulfan-based myeloablative regimen and reduced-intensity chemotherapy using cyclophosphamide. In this study, we showed no significant differences in EFS, OS, TRM, and GVHD, except for acute GVHD grades II-IV, between BMT and PBSCT from sibling donors, using ATG (a total of 7.5 mg/kg). Therefore, PB collection, which is less invasive for donors and less labor-intensive for doctors, could also be considered an acceptable SC source for sibling donor HSCT in children.

Tandem autologous hematopoietic stem cell transplantation for patients with multiple myeloma: a systematic review and meta-analysis.

To evaluate whether patients with multiple myeloma (MM) could benefit from tandem autologous hematopoietic stem cell transplantation (auto-HSCT), PubMed, Embase, Web of Science and Cochrane Library databases were systematically searched, and 10 eligible studies were included after data extraction and quality evaluation. Meta-analysis showed that compared to single autologous hematopoietic stem cell transplantation, tandem auto-HSCT does not improve OS, EFS or efficacy in MM patients, and may even lead to higher treatment-related mortality (TRM). MM patients who received autologous tandem allogeneic HSCT did not achieve better response compared to tandem autologous HSCT. In summary, compared to single autologous hematopoietic stem cell transplantation, tandem autologous hematopoietic stem cell transplantation cannot provide survival advantages for MM patients, and MM patients cannot benefit from autologous tandem allogeneic hematopoietic stem cell transplantation.