Artificial intelligence methods to estimate overall mortality and non-relapse mortality following allogeneic HCT in the modern era: an EBMT-TCWP study.

Allogeneic haematopoietic cell transplantation (alloHCT) has curative potential counterbalanced by its toxicity. Prognostic scores fail to include current era patients and alternative donors. We examined adult patients from the EBMT registry who underwent alloHCT between 2010 and 2019 for oncohaematological disease. Our primary objective was to develop a new prognostic score for overall mortality (OM), with a secondary objective of predicting non-relapse mortality (NRM) using the OM score. AI techniques were employed. The model for OM was trained, optimized, and validated using 70%, 15%, and 15% of the data set, respectively. The top models, "gradient boosting" for OM (AUC = 0.64) and "elasticnet" for NRM (AUC = 0.62), were selected. The analysis included 33,927 patients. In the final prognostic model, patients with the lowest score had a 2-year OM and NRM of 18 and 13%, respectively, while those with the highest score had a 2-year OM and NRM of 82 and 93%, respectively. The results were consistent in the subset of the haploidentical cohort (n = 4386). Our score effectively stratifies the risk of OM and NRM in the current era but do not significantly improve mortality prediction. Future prognostic scores can benefit from identifying biological or dynamic markers post alloHCT.

The effect of zofenopril on the cardiovascular system of spontaneously hypertensive rats treated with the ACE2 inhibitor MLN-4760.

BACKGROUND: Angiotensin converting enzyme 2 (ACE2) plays a crucial role in the infection cycle of SARS-CoV-2 responsible for formation of COVID-19 pandemic. In the cardiovascular system, the virus enters the cells by binding to the transmembrane form of ACE2 causing detrimental effects especially in individuals with developed hypertension or heart disease. Zofenopril, a H2S-releasing angiotensin-converting enzyme inhibitor (ACEI), has been shown to be effective in the treatment of patients with essential hypertension; however, in conditions of ACE2 inhibition its potential beneficial effect has not been investigated yet. Therefore, the aim of the study was to determine the effect of zofenopril on the cardiovascular system of spontaneously hypertensive rats, an animal model of human essential hypertension and heart failure, under conditions of ACE2 inhibition induced by the administration of the specific inhibitor MLN-4760 (MLN). RESULTS: Zofenopril reduced MLN-increased visceral fat to body weight ratio although no changes in systolic blood pressure were recorded. Zofenopril administration resulted in a favorable increase in left ventricle ejection fraction and improvement of diastolic function regardless of ACE2 inhibition, which was associated with increased H2S levels in plasma and heart tissue. Similarly, the acute hypotensive responses induced by acetylcholine, L-NAME (NOsynthase inhibitor) and captopril (ACEI) were comparable after zofenopril administration independently from ACE2 inhibition. Although simultaneous treatment with zofenopril and MLN led to increased thoracic aorta vasorelaxation, zofenopril increased the NO component equally regardless of MLN treatment, which was associated with increased NO-synthase activity in aorta and left ventricle. Moreover, unlike in control rats, the endogenous H2S participated in maintaining of aortic endothelial function in MLN-treated rats and the treatment with zofenopril had no impact on this effect. CONCLUSIONS: Zofenopril treatment reduced MLN-induced adiposity and improved cardiac function regardless of ACE2 inhibition. Although the concomitant MLN and zofenopril treatment increased thoracic aorta vasorelaxation capacity, zofenopril increased the participation of H2S and NO in the maintenance of endothelial function independently from ACE2 inhibition. Our results confirmed that the beneficial effects of zofenopril were not affected by ACE2 inhibition, moreover, we assume that ACE2 inhibition itself can lead to the activation of cardiovascular compensatory mechanisms associated with Mas receptor, nitrous and sulfide signaling.

Management of adults and children receiving CAR T-cell therapy: 2021 best practice recommendations of the European Society for Blood and Marrow Transplantation (EBMT) and the Joint Accreditation Committee of ISCT and EBMT (JACIE) and the European Haematology Association (EHA).

BACKGROUND: Several commercial and academic autologous chimeric antigen receptor T-cell (CAR-T) products targeting CD19 have been approved in Europe for relapsed/refractory B-cell acute lymphoblastic leukemia, high-grade B-cell lymphoma and mantle cell lymphoma. Products for other diseases such as multiple myeloma and follicular lymphoma are likely to be approved by the European Medicines Agency in the near future. DESIGN: The European Society for Blood and Marrow Transplantation (EBMT)-Joint Accreditation Committee of ISCT and EBMT (JACIE) and the European Haematology Association collaborated to draft best practice recommendations based on the current literature to support health care professionals in delivering consistent, high-quality care in this rapidly moving field. RESULTS: Thirty-six CAR-T experts (medical, nursing, pharmacy/laboratory) assembled to draft recommendations to cover all aspects of CAR-T patient care and supply chain management, from patient selection to long-term follow-up, post-authorisation safety surveillance and regulatory issues. CONCLUSIONS: We provide practical, clinically relevant recommendations on the use of these high-cost, logistically complex therapies for haematologists/oncologists, nurses and other stakeholders including pharmacists and health sector administrators involved in the delivery of CAR-T in the clinic.

Metabolic syndrome and cardiovascular disease after haematopoietic cell transplantation (HCT) in adults: an EBMT cross-sectional non-interventional study.

Metabolic syndrome (MetS) is associated with cardiovascular disease in the general population and is also a potential cardiovascular risk factor in survivors of haematopoietic cell transplantation (HCT). We report an EBMT cross-sectional, multi-centre, non-interventional study of 453 adult HCT patients surviving a minimum of 2 years post-transplant attending routine follow-up HCT and/or late effects clinics in 9 centres. The overall prevalence of MetS was 37.5% rising to 53% in patients >50 years of age at follow-up. There were no differences in rates of MetS between autologous and allogeneic HCT survivors, nor any association with graft-versus-host disease (GvHD) or current immunosuppressant therapy. Notably, there was a significantly higher occurrence of cardiovascular events (CVE, defined as cerebrovascular accident, coronary heart disease or peripheral vascular disease) in those with MetS than in those without MetS (26.7% versus 9%, p < 0.001, OR 3.69, 95% CI 2.09-6.54, p < 0.001), and, as expected, MetS and CVE were age-related. Unexpectedly, CVE were associated with occurrence of second malignancy. Screening for and management of MetS should be integrated within routine HCT long-term follow-up care for both allogeneic and autologous HCT survivors. Further research is warranted, including randomised controlled trials of interventional strategies and mechanistic studies of cardiovascular risk in HCT survivors.

Management of growth failure and growth hormone deficiency after pediatric allogeneic HSCT: Endocrinologists are of importance for further guidelines and studies.

Growth failure (GF) is a frequent problem after pediatric allogeneic hematopoietic stem cell transplantation (HSCT). Growth hormone deficiency (GHD) occurs in 20 to 85%, but published data on the efficacy of growth hormone treatment (GHT) are conflicting. Currently, there are no recommendations on screening for and treatment of GHD after HSCT. We aimed to describe the management of endocrine follow-up (FU)and details of GHT within European Society for Blood and Marrow Transplantation (EBMT) centers.In a retrospective questionnaire study, all EBMT centers performing pediatric HSCT were invited. Results were evaluated in correlation with the structure of endocrine aftercare (HSCT-clinicians and endocrinologists).The majority of centers (80%) reported endocrine FU by an endocrinologist - either within the HSCT-center or in a separate endocrine clinic. Fifty-four percent reported FU outside of the HSCT-center. As diagnostic tests the insulin-like growth factor IGF-I and insulin-like growth factor binding protein IGFBP3, insulin tolerance test and arginine stimulation test were most frequently used. Sixty-four percent of centers performed GHT and endocrinologists were more likely to prescribe GH (74%) compared to HSCT-clinicians (33%). The most frequent indication for GHT was GHD in 60%, with a distinct different approach of endocrinologists in comparison with HSCT-clinicians.Our study reveals substantial variation in practice and emphasizes the need for endocrine aftercare performed by dedicated endocrinologists in close collaboration with the HSCT-center. Our results indicate that the management of GHT depends on the structure of endocrine aftercare, which is important for the future development and distribution of studies and guidelines.

Current Practice in Vitamin D Management in Allogeneic Hematopoietic Stem Cell Transplantation: A Survey by the Transplant Complications Working Party of the European Society for Blood and Marrow Transplantation.

Beyond its impact on bone health, numerous studies have investigated the immune-regulatory properties of vitamin D and shown how its deficiency can affect outcomes in allogeneic hematopoietic stem cell transplantation (HSCT), particularly in acute or chronic graft-versus-host disease. This survey, carried out by the Transplant Complications Working Party of the European Society for Blood and Marrow Transplantation (EBMT), describes the current clinical practice discrepancies across the EBMT HSCT programs. We therefore recommend the development of evidence-based guidelines to standardize evaluation criteria and to harmonize the management of vitamin D deficiency in patients undergoing allogeneic HSCT.

Azacitidine for Relapse After Allogeneic Stem Cell Transplantation-Single-Center Study.

BACKGROUND: Relapse is the leading cause of treatment failure for myeloid malignancies treated with allogeneic hematopoietic stem cell transplantation. Treatment options are very limited and use of azacitidine is one of the available options. METHODS: This was a retrospective, single-institution study. Of 28 evaluated patients, 18 were males, and the median age was 60 years (range, 15-78). There were 15 patients with acute myeloid leukemia, 8 with myelodysplastic syndrome, 4 with chronic myelomonocytic leukemia, and 1 with primary myelofibrosis. Ten patients received azacitidine for overt relapse, 14 received it as a preemptive therapy, and 4 others received it as maintenance treatment after allo-hematopoietic cell transplant (HSCT). Eleven patients received a donor lymphocyte infusion (DLI). RESULTS: The patients received median 5 (1-9) cycles of azacitidine in preemptive and maintenance therapy and median 2.5 (1-9) cycles in patients with relapse. Thirty-nine percent of patients received DLIs. Median overall survival was 6.1 months (95% CI, 0.7-13) for relapse therapy vs 21.2 months (95% CI, 8.4-inf) for preemptive therapy. Among patients treated for relapse, 30% achieved temporary disease control and underwent the second allo-HSCT. A complete, cytogenetic remission was achieved in 50% of patients and stable minimal residual disease in 14% of patients in a group with preemptive therapy. Toxicity was considerable; neutropenia (71%), anemia (14%), thrombocytopenia (36%), and serious infections (36%) were observed in the preemptive setting. CONCLUSIONS: These data support the notion that azacitidine is best used as a preemptive therapy against relapse for patients after allo-HSCT performed for myeloid malignancy. Applying azacitidine as therapy for ongoing relapse after allo-HSCT may lead to stable disease and allow for better performance of the second allo-HSCT.

Pericarditis in Patients With Chronic Graft-vs-Host Disease.

BACKGROUND: There are only a few cases of pericarditis complications following allogeneic bone marrow transplantation described in the literature and there are no data available on the risk and frequency of this condition. The aim of this study was to assess the frequency of exudative pericarditis complicating chronic graft-vs-host disease in allogeneic hematopoietic cell transplant recipients. METHODS: Retrospective analysis involved a group of 105 patients of the Outpatient Transplantation Service of the Department of Hematology, Medical University of Warsaw, who received transplants in the years 2010-2016 and were evaluated for the years 2014-2016. In this group, 50 patients suffered from chronic graft-vs-host disease (cGVHD), including 24 with moderate or severe disease. Cardiology parameters evaluated included electrocardiography, echocardiography, N-terminal prohormone of brain natriuretic peptide (NT-proBNP), and systematic clinical follow-up. RESULTS: Pericarditis was diagnosed in 6 patients (aged 20-56 years) within 4 to 23 months after allogenic hematopoietic stem cell transplantation. All patients suffered from severe cGVHD with involvement of at least 2 organs but none had earlier history of heart disease. All patients had elevated NT-proBNP and demonstrated signs of heart insufficiency grade II or III according to the New York Heart Association. There were no major changes in electrocardiogram. Only 1 patient improved following glucocorticosteroids as monotherapy, while others required complex approaches including tacrolimus plus sirolimus, rituximab, and extracorporeal photopheresis. CONCLUSION: Late pericarditis may occur in up to 5% of allogenic hematopoietic stem cell transplantation survivors, primarily affecting patients with moderate and severe grade cGVHD. It requires escalation of immunosuppressive treatment but usually has favorable outcome. Early diagnosis may be achieved by systematic NT-proBNP testing and periodic echocardiograph evaluation.

Activation of the complement cascade enhances motility of leukemic cells by downregulating expression of HO-1.

As a crucial arm of innate immunity, the complement cascade (ComC) is involved both in mobilization of normal hematopoietic stem/progenitor cells (HSPCs) from bone marrow (BM) into peripheral blood and in their homing to BM. Despite the fact that ComC cleavage fragments alone do not chemoattract normal HSPCs, we found that leukemia cell lines as well as clonogenic blasts from chronic myeloid leukemia and acute myeloid leukemia patients respond robustly to C3 and C5 cleavage fragments by chemotaxis and increased adhesion. This finding was supported by the detection of C3a and C5a receptors in cells from human malignant hematopoietic cell lines and patient blasts at the mRNA (reverse transcriptase-polymerase chain reaction) and protein level (fluorescence-activated cell sorting), and by the demonstration that these receptors respond to stimulation by C3a and C5a by phosphorylation of p42/44 and p38 mitogen-activated protein kinases (MAPK), and protein kinase B (PKB/AKT). We also found that inducible heme oxygenase 1 (HO-1) is a negative regulator of ComC-mediated trafficking of leukemic cells, and that stimulation of leukemic cells by C3 or C5 cleavage fragments activates p38 MAPK, which downregulates HO-1 expression, rendering cells more mobile. We conclude that activation of the ComC in leukemia/lymphoma patients (for example, as a result of accompanying infections) enhances the motility of malignant cells and contributes to their spread in a p38 MAPK-HO-1-dependent manner. Therefore, inhibition of p38 MAPK or upregulation of HO-1 by small-molecule modulators would have a beneficial effect on ameliorating cell migration-mediated expansion of leukemia/lymphoma cells when the ComC becomes activated.

The EBMT-ELN working group recommendations on the prophylaxis and treatment of GvHD: a change-control analysis.

In 2013, recommendations for a standardized practice in the prophylaxis and treatment of GvHD were adopted and published by the European Society for Blood and Marrow Transplantation and the European LeukemiaNet. One year later, all 341 European Society for Blood and Marrow Transplantation centres performing allogeneic haematopoietic stem cell transplantation were contacted for a change-control analysis and asked to fill in a questionnaire; 111 centres (33%) responded. Of these, 83% had been aware of the recommendations. Paediatric centres (P=0.004), centres with shorter programme duration (P=0.049), not JACIE (the Joint Accreditation Committee of the International Society for Cellular Therapy and the European Society for Blood and Marrow Transplantation)-accredited centres (P=0.010) and centres from middle-income countries (P=0.033) were more likely to be unaware of the recommendations. Thirty-eight per cent of the centres regarded the recommendations as relevant guidelines affecting their policies, 61% as interesting information. Thirty per cent had decided to make changes in their institutional protocols based on the recommendations. More than 80% were willing to use the recommendations for a control arm in randomized studies. This survey shows that the published recommendations had some, though insufficient, impact on the strategies and methods of allogeneic haematopoietic stem cell transplantation applied by the centres. It also identified some of the weaknesses to be addressed when releasing recommendations in the future.

Rhinosinusitis in Acute Leukemia Patients Undergoing Allogeneic Stem Cell Transplantation-A Single-Center Experience.

BACKGROUND: Although rhinosinusitis constitutes a major clinical problem in general population, data on rhinosinusitis in patients undergoing allogeneic hematopoietic stem cell transplantation (alloHSCT) are scarce. Therefore, the aim of the study was to assess the frequency of rhinosinusitis, the impact of rhinosinusitis on post-alloHSCT outcome, and to analyze risk factors potentially predisposing to rhinosinusitis. METHODS: Retrospective analysis of acute leukemia patients undergoing alloHSCT. RESULTS: A total of 87 patients (49 male), with a median age of 36 years (range, 18-58), transplanted from 1999 to 2010, were enrolled; 61 patients suffered from acute myeloid leukemia (AML) and 26 of acute lymphoblastic leukemia (ALL). Fifteen patients (17.2%) experienced rhinosinusitis before transplantation, among whom 5 (33%) experienced rhinosinusitis after alloHSCT; 22 patients (25.3%), 12 AML and 10 ALL, experienced rhinosinusitis after alloHSCT. The median time to rhinosinusitis was 200 days (range, 1-2,044). 11 patients experienced rhinosinusitis during the 1st 100 days after transplantation, 8 during the 1st 30 days. Post-alloHSCT rhinosinusitis did not affect overall survival of transplant patients (P = .35). In univariate analysis only total body irradiation as part of conditioning (odds ratio [OR], 2.78; 95% CI, 1-7.77) and previous nasal packing (OR, 5.18; 95% CI, 1.22-23.43) were associated with higher incidence of rhinosinusitis. In multivariate analysis, none of the analyzed parameters was shown to have an impact on rhinosinusitis development. CONCLUSIONS: Rhinosinusitis is a frequent medical condition in patients undergoing alloHSCT. The overall survival of patients developing rhinosinusitis after HSCT is similar to survival of patients who do not. No risk factors for developing rhinosinusitis could be identified.

Azacitidine Use After Allogeneic Stem Cell Transplantation-Results From the Polish Adult Leukemia Group.

BACKGROUND: Relapse of primary hematologic disease constitutes an important reason for failure of allogeneic hematopoietic stem cell transplantation (alloHSCT). There are very few treatment modalities for this indications. Therefore, there is a need for novel effective therapies and even more for the prevention of relapse. There are scarce data that azacitidine can be used for these purposes. METHODS: At the Polish Adult Leukemia Group, we retrospectively analyzed the results of azacitidine treatment after alloHSCT. Relapsing patients, patients with minimal residual disease/mixed chimerism, and patients in complete remission with high risk of relapse were analyzed separately. There were 17 patients, 6 with myelodysplastic syndrome, 11 with acute myeloid leukemia, 8 male, and overall median age of 56 years (range, 15-78); 7 patients received donor lymphocyte infusion (DLI). RESULTS: Patients treated because of relapse received a median of 3 (range, 1-6) cycles of azacitidine, patients receiving preemptive treatment received a median of 4 cycles (range, 2-6), and those on maintenance received a median of 5 cycles (range, 3-5). Toxicity was considerable, especially in relapse-neutropenia (67%), anemia (67%), thrombocytopenia (100%), serious infections (78%)-and preemptive settings. Median overall survival of patients treated for relapse reached 6.8 months (95% confidence interval [CI], 0.7-∞), with better survival observed in patients with temporary disease control (7.7 vs 4.7 mo) and without previous exposure to azacitidine (7.7 vs 3.4 mo). One-year overall survival reached 75% (95% CI, 13%-96%) for preemptive and 50% (95% CI, 0%-91%) for maintenance treatment. DLI did not aggravate graft-versus-host disease. CONCLUSIONS: Effectiveness of azacitidine in relapsing patients is disappointing. Azacitidine seems to be promising in preemptive and maintenance settings. Toxicity is considerable. Further research is needed.

Secondary solid cancer screening following hematopoietic cell transplantation.

Hematopoietic stem cell transplant (HCT) recipients have a substantial risk of developing secondary solid cancers, particularly beyond 5 years after HCT and without reaching a plateau overtime. A working group was established through the Center for International Blood and Marrow Transplant Research and the European Group for Blood and Marrow Transplantation with the goal to facilitate implementation of cancer screening appropriate to HCT recipients. The working group reviewed guidelines and methods for cancer screening applicable to the general population and reviewed the incidence and risk factors for secondary cancers after HCT. A consensus approach was used to establish recommendations for individual secondary cancers. The most common sites include oral cavity, skin, breast and thyroid. Risks of cancers are increased after HCT compared with the general population in skin, thyroid, oral cavity, esophagus, liver, nervous system, bone and connective tissues. Myeloablative TBI, young age at HCT, chronic GVHD and prolonged immunosuppressive treatment beyond 24 months were well-documented risk factors for many types of secondary cancers. All HCT recipients should be advised of the risks of secondary cancers annually and encouraged to undergo recommended screening based on their predisposition. Here we propose guidelines to help clinicians in providing screening and preventive care for secondary cancers among HCT recipients.

Allogeneic hematopoietic stem cell transplantation in solid organ transplant recipients: a retrospective, multicenter study of the EBMT.

We conducted a questionnaire survey of the 565 European Society for Blood and Marrow Transplantation centers to analyze the outcome of allogeneic hematopoietic stem cell transplantation (alloSCT) in recipients of solid organ transplantation (SOT). We investigated 28 patients with malignant (N = 22) or nonmalignant diseases (N = 6), who underwent 31 alloSCT procedures: 12 after kidney, 13 after liver and 3 after heart transplantation. The incidence of solid organ graft failure at 60 months after first alloSCT was 33% (95% confidence interval [CI], 16-51%) for all patients, 15% (95% CI, 2-40%) for liver recipients and 50% (95% CI, 19-75%) for kidney recipients (p = 0.06). The relapse rate after alloSCT (22%) was low following transplantation for malignant disorders, despite advanced stages of malignancy. Overall survival at 60 months after first alloSCT was 40% (95% CI, 19-60%) for all patients, 51% (95% CI, 16-86%) for liver recipients and 42% (95% CI, 14-70%) for kidney recipients (p = 0.39). In summary, we show that selected SOT recipients suffering from hematologic disorders may benefit from alloSCT and experience enhanced long-term survival without loss of organ function.

Autologous haematopoietic stem cell mobilisation in multiple myeloma and lymphoma patients: a position statement from the European Group for Blood and Marrow Transplantation.

Autologous haematopoietic SCT with PBSCs is regularly used to restore BM function in patients with multiple myeloma or lymphoma after myeloablative chemotherapy. Twenty-eight experts from the European Group for Blood and Marrow Transplantation developed a position statement on the best approaches to mobilising PBSCs and on possibilities of optimising graft yields in patients who mobilise poorly. Choosing the appropriate mobilisation regimen, based on patients' disease stage and condition, and optimising the apheresis protocol can improve mobilisation outcomes. Several factors may influence mobilisation outcomes, including older age, a more advanced disease stage, the type of prior chemotherapy (e.g., fludarabine or melphalan), prior irradiation or a higher number of prior treatment lines. The most robust predictive factor for poor PBSC collection is the CD34(+) cell count in PB before apheresis. Determination of the CD34(+) cell count in PB before apheresis helps to identify patients at risk of poor PBSC collection and allows pre-emptive intervention to rescue mobilisation in these patients. Such a proactive approach might help to overcome deficiencies in stem cell mobilisation and offers a rationale for the use of novel mobilisation agents.

Uptake and use of recommendations for the diagnosis, severity scoring and management of chronic GVHD: an international survey of the EBMT-NCI Chronic GVHD Task Force.

In 2005, the National Institutes of Health (NIH) consensus conference published a series of papers recommending methods to improve the conduct of clinical trials in chronic GVHD. Although the NIH recommendations were primarily aimed at strengthening research, several papers addressed issues relevant for clinical practice, particularly diagnosis, severity scoring, and ancillary and supportive care practices. We conducted an international survey to assess the uptake of these recommendations, identify barriers to greater use and document the use and perceived effectiveness of available treatments. The response rate for the American survey of 1387 practitioners was 21.8%, and it was 24.6% for 407 centers surveyed in Europe, Asia, Australia and Africa. Most respondents were familiar with the NIH consensus recommendations (94-96%) and used them in practice. Multiple barriers to greater use were reported. Besides lack of time (55-62%), unfamiliarity with the recommendations, scarcity of evidence supporting the impact of recommendations on outcomes, insufficient training/experience in chronic GVHD management and inaccessibility of subspecialists were also endorsed. Systemic corticosteroids were reported to be the most effective treatment for chronic GVHD, but many others were perceived to have moderate or great success. Therapeutic management of steroid-refractory chronic GVHD was identified as the highest priority for research.

Donor lymphocyte infusions for the treatment of chronic myeloid leukemia relapse following peripheral blood or bone marrow stem cell transplantation.

Peripheral blood used as a source of stem cells for transplantation (PBSCT) is known to exert stronger immune-mediated effects compared with BM (BMT). We decided to retrospectively analyze the impact of stem cell source on the OS of CML patients who relapsed after either matched related donor PBSCT (N=168) or BMT (N=216) and were treated with donor lymphocyte infusions (DLI). Univariate analysis revealed a lower probability of OS after DLI in patients relapsing after PBSCT vs BMT (66% vs 79% at 5 years, P=0.013). However, a multivariate Cox analysis did not reveal any significant impact of PBSCT as a risk factor for decreased OS for patients transplanted in first chronic phase (CP1; hazard ratio (HR) 1.036, 95% confidence interval (CI) 0.619-1.734). A statistical interaction term suggested that the impact of stem cell source on OS after DLI was different for those transplanted in advanced phases (negative impact of previous PBSCT-HR 2.176, 95% CI 0.930-5.091). In summary, the stem cell source does not affect the OS of CML patients who underwent PBSCT in CP1, relapsed and were treated with DLI. However, when the patients were transplanted in advanced phases, previous PBSCT seems to negatively affect OS after DLI compared with BMT.