Applicability of the acute leukemia (AL) - EBMT score as a prognostic model for allogeneic hematopoietic stem cell transplantation: a single-center, prospective, cohort study at a reference transplant center in Brazil

Abstract Introduction The Acute Leukemia-European Society for Blood and Marrow Transplantation (AL-EBMT) risk score was recently developed and validated by Shouval et al. Objective To assess the ability of this score in predicting the 2-year overall survival (OS-2), leukemia-free survival (LFS-2) and transplant-related mortality (TRM) in acute leukemia (AL) adult patients undergoing a first allogeneic hematopoietic stem cell transplant (HSCT) at a transplant center in Brazil. Methods In this prospective, cohort study, we used the formula published by Shouval et al. to calculate the AL-EBMT score and stratify patients into three risk categories. Results A total of 79 patients transplanted between 2008 and 2018 were analyzed. The median age was 38 years. Acute myeloid leukemia was the most common diagnosis (68%). Almost a quarter of the cases were at an advanced stage. All hematopoietic stem cell transplantations (HSCTs) were human leukocyte antigen-matched (HLA-matched) and the majority used familial donors (77%). Myeloablative conditioning was used in 92% of the cases. Stratification according to the AL-EBMT score into low-, intermediate- and high-risk groups yielded the following results: 40%, 12% and 47% of the cases, respectively. The high scoring group was associated with a hazard ratio of 2.1 (p= 0.007), 2.1 (p= 0.009) and 2.47 (p= 0.01) for the 2-year OS, LFS and TRM, respectively. Conclusion This study supports the ability of the AL-EBMT score to reasonably predict the 2-year post-transplant OS, LFS and TRM and to discriminate between risk categories in adult patients with AL, thus confirming its usefulness in clinical decision-making in this setting. Larger, multicenter studies may further help confirm these findings.

Applicability of the acute leukemia (AL) - EBMT score as a prognostic model for allogeneic hematopoietic stem cell transplantation: a single-center, prospective, cohort study at a reference transplant center in Brazil.

INTRODUCTION: The Acute Leukemia-European Society for Blood and Marrow Transplantation (AL-EBMT) risk score was recently developed and validated by Shouval et al. OBJECTIVE: To assess the ability of this score in predicting the 2-year overall survival (OS-2), leukemia-free survival (LFS-2) and transplant-related mortality (TRM) in acute leukemia (AL) adult patients undergoing a first allogeneic hematopoietic stem cell transplant (HSCT) at a transplant center in Brazil. METHODS: In this prospective, cohort study, we used the formula published by Shouval et al. to calculate the AL-EBMT score and stratify patients into three risk categories. RESULTS: A total of 79 patients transplanted between 2008 and 2018 were analyzed. The median age was 38 years. Acute myeloid leukemia was the most common diagnosis (68%). Almost a quarter of the cases were at an advanced stage. All hematopoietic stem cell transplantations (HSCTs) were human leukocyte antigen-matched (HLA-matched) and the majority used familial donors (77%). Myeloablative conditioning was used in 92% of the cases. Stratification according to the AL-EBMT score into low-, intermediate- and high-risk groups yielded the following results: 40%, 12% and 47% of the cases, respectively. The high scoring group was associated with a hazard ratio of 2.1 (p = 0.007), 2.1 (p = 0.009) and 2.47 (p = 0.01) for the 2-year OS, LFS and TRM, respectively. CONCLUSION: This study supports the ability of the AL-EBMT score to reasonably predict the 2-year post-transplant OS, LFS and TRM and to discriminate between risk categories in adult patients with AL, thus confirming its usefulness in clinical decision-making in this setting. Larger, multicenter studies may further help confirm these findings.

Validation of a formula predictive of peripheral blood stem cell yield and successful collection in healthy allogeneic donors

ABSTRACT Background: An efficient mobilization and collection of peripheral blood stem cells (PBSCs) are crucial to optimize engraftment in the recipient. We aim to validate a formula that predicted CD34+ cell yield and to describe variables that correlated with high yield mobilization and collection in healthy donors. Methods: We retrospectively analyzed clinical and laboratory data from healthy donors who underwent PBSC collection from 2006 to 2015. The predicted number of collected cells was calculated using the following formula: Total number of CD34+ (cells × 106/kg) yield = [(peripheral CD34+ cells/µL) × (0.43)/recipient body weight (kg)] × total liters processed. Results: We evaluated 338 collections from 307 allogeneic PBSC donors. The predicted versus the observed number of CD34+ cells/kg collected yielded an r-value of 0.775 (0.726-0.816; p < 0.0001). Overall, 55.7% donors had an acceptable mobilization level. Donors with a body weight <67 kg were less likely to yield a satisfactory CD34+ cell count (OR = 0.44; 95% CI 0.24-0.81), while a white blood cell (WBC) count >40 × 109/L (OR = 3.69; 2.11-6.46) and platelet count ≥200 × 109/L (OR = 2.09; 1.26-3.47) on the day of collection predicted a good level of mobilization. Predictors of a CD34+ cell yield/kg of ≥4 × 106 with only one apheresis session were: circulating CD34+ cells/µL >40 (OR = 16; 6.94-36.93), hemoglobin ≥14 g/dL (OR = 3.40; 1.53-7.57), WBC >40 × 109/L (OR = 4.61; 2.10-10.10) on the first collection day, and a positive delta weight between donor and recipient (OR = 3.10; 1.36-7.06). Conclusion: The formula for predicting CD34+ cell yield is accurate and suggests the optimal length of time for successful leukapheresis. Validation of the predictors of successful mobilization will help to further refine PBSC leukapheresis procedures.

Validation of a formula predictive of peripheral blood stem cell yield and successful collection in healthy allogeneic donors.

BACKGROUND: An efficient mobilization and collection of peripheral blood stem cells (PBSCs) are crucial to optimize engraftment in the recipient. We aim to validate a formula that predicted CD34+ cell yield and to describe variables that correlated with high yield mobilization and collection in healthy donors. METHODS: We retrospectively analyzed clinical and laboratory data from healthy donors who underwent PBSC collection from 2006 to 2015. The predicted number of collected cells was calculated using the following formula: Total number of CD34+ (cells×106/kg) yield=[(peripheral CD34+ cells/µL)×(0.43)/recipient body weight (kg)]×total liters processed. RESULTS: We evaluated 338 collections from 307 allogeneic PBSC donors. The predicted versus the observed number of CD34+ cells/kg collected yielded an r-value of 0.775 (0.726-0.816; p<0.0001). Overall, 55.7% donors had an acceptable mobilization level. Donors with a body weight <67kg were less likely to yield a satisfactory CD34+ cell count (OR=0.44; 95% CI 0.24-0.81), while a white blood cell (WBC) count >40×109/L (OR=3.69; 2.11-6.46) and platelet count ≥200×109/L (OR=2.09; 1.26-3.47) on the day of collection predicted a good level of mobilization. Predictors of a CD34+ cell yield/kg of ≥4×106 with only one apheresis session were: circulating CD34+ cells/µL >40 (OR=16; 6.94-36.93), hemoglobin ≥14g/dL (OR=3.40; 1.53-7.57), WBC >40×109/L (OR=4.61; 2.10-10.10) on the first collection day, and a positive delta weight between donor and recipient (OR=3.10; 1.36-7.06). CONCLUSION: The formula for predicting CD34+ cell yield is accurate and suggests the optimal length of time for successful leukapheresis. Validation of the predictors of successful mobilization will help to further refine PBSC leukapheresis procedures.