A New Tool Supporting the Selection of the Best Hematopoietic Stem Cell Donor by Modelling Local Own Real-World Data

The selection of the best allogeneic donor for each specific patient is crucial for the success of allogeneic hematopoietic stem cell transplantation (HSCT). Besides the well-known patient’s characteristics, donor-related variables such as patient-donor histocompatibility and donor age are of utmost importance for the outcome after HSCT. However, there is still debate on the definition of the best stem cell donor when multiple suitable donors exist. By using own data from two transplant centers, we here developed a calculator able to provide the 2-year patients’ overall survival (OS) associated to each of the potential donor options during the selection process. Data on n=737 HSCTs performed from January 2010 to July 2022 have been retrospectively obtained. Donor types were HLA-identical siblings, unrelated or related haploidentical. Cox regression and parametric model indicates patients’ age, disease, comorbidity index and donor type as significant variables (p<0.05) able to predict 2-year OS with robustness (concordance index: 0.677). Estimates are provided with the three donor options for each single, specific patient. Of note, estimates express real data of the transplant centers and reflect their actual experience. In conclusion, we here present the prototype of a new tool for the calculation of patients’ outcome according to the stem cell donor type, guiding transplant physicians during the process of donor selection before HSCT. The novelty of this approach relies on the use of real data from the investigating centers, reflecting the local clinical experience. Improvements are planned by filling additional information and pooling data from more centers.