Risk factors for secondary poor graft function after bone marrow transplantation in children with acquired aplastic...

Area of Science:

• Hematology
• Pediatric Oncology
• Transplantation Immunology

Background:

• Post-transplant graft failure (PGF) is a significant cause of cytopenia following hematopoietic stem cell transplantation for acquired aplastic anemia (AA).
• An increased incidence of PGF, particularly secondary pure red cell aplasia (sPGF), has been observed after implementing the fludarabine and cyclophosphamide (FLU/CY) conditioning regimen in pediatric AA patients.

Purpose of the Study:

• To identify risk factors associated with the development of sPGF in children with acquired AA undergoing allogeneic bone marrow transplantation (BMT).

Main Methods:

• Retrospective analysis of clinical data from 49 pediatric patients with acquired AA who received allogeneic BMT between 1997 and 2016.
• Comparison of sPGF incidence between patients conditioned with FLU/CY and those conditioned with non-FLU/CY regimens.
• Multivariate analysis to determine significant risk factors for sPGF.

Main Results:

• Seven out of 49 patients developed sPGF, with a 5-year cumulative incidence (CI) of 0.15.
• Patients conditioned with the FLU/CY regimen had a significantly higher 5-year CI of sPGF (0.36) compared to those with non-FLU/CY regimens (0.06) (P = .01).
• The FLU/CY regimen was confirmed as a significant risk factor for sPGF (hazard ratio, 6.12; P = .03). Spontaneous recovery occurred in 5 patients, with a 10-year CI of spontaneous trilineage recovery of 0.83.

Conclusions:

• The FLU/CY conditioning regimen is a significant risk factor for sPGF development in pediatric patients with acquired AA undergoing allogeneic BMT.
• Spontaneous recovery from sPGF is possible and occurs in a majority of cases without intervention.
• Further research is warranted to establish optimal conditioning regimens for children with acquired AA to mitigate sPGF risk.