From self-construal to trait- and state-fear of missing out: the roles of need to belong and active social media use.

is a potentially life-saving therapy for hematologic and bone marrow cancers (eg, leukemia, lymphoma, multiple myeloma, and myelodysplastic syndromes)and nonmalignant conditions (eg, sickle cell disease, aplastic anemia) in adults and children. Autologous stem cell transplant (auto-HSCT) involves the transplant of a patient’s own stem cells, while allogeneic stem cell transplant (allo-HSCT) involves the transplant of a related or unrelated donor’s stem cells ( in the ). The Center for International Blood and Marrow Transplant Research reported that approximately 20 000 HSCTs were performed in the US in 2023, of which 11 139 were auto-HSCT and 8218 were allo-HSCT. For allo-HSCT, selection of donors relies on typing of human leukocyte antigen (HLA) genes at HLA-A, -B, -C, -and DRB1 loci. However, at donor recruitment, many donor registries currently genotype 9 HLA loci: , -, -, -, -, -, -, -, and -. Matched sibling donors are typically the ideal donor for allo-HSCT, but only 30% of patients have such a donor. For the remaining 70% of patients, alternative sources of stem cells are used. In 2022, the largest donor source of allo-HSCT was HLA-matched unrelated donors (45%); other donor sources included haploidentical donor (ie, related donor in which HLA of donor stem cells match half of the HLA in recipients; 21%), matched related donor (20%), mismatched unrelated donor (ie, unrelated donor HLA cells partially match that of recipient HLA cells; 9%), mismatched related donor (ie, related donor HLA cells partially match that of recipient HLA cells; 1%), and umbilical cord blood from unrelated donors (4%). Allo-HSCT can be performed using peripheral blood stem cells (PBSCs) or stem cells obtained from the bone marrow or umbilical cord blood. Clinicians make decisions about the appropriate donor and type of stem cells used in allo-HSCT based on factors such as donor age, patient age, disease, and patient preference. Currently, PBSCs are the source of stem cells for more than 85% of allo-HSCT procedures, although bone marrow stem cells are preferred for pediatric patients because they are associated with decreased risk of chronic graft-vs-host disease (GVHD) compared with PBSCs in this patient population.