Hematopoietic stem cell transplantation (HSCT) is safe and efficient in children with Diamond-Blackfan anemia (DBA), especially in the absence of a matched sibling donor (MSD) or matched unrelated donor (UD), according to a study published in Blood Advances.
DBA is associated with congenital anomalies and cancer predisposition. Treatment for DBA includes regular transfusions with chelation and corticoid therapies. Patients that remain transfusion dependent are at risk of complications due to iron overload and rigorous chelation therapy is indicated. HSCT is mainly utilized in severe DBA cases and those with secondary myelodysplastic syndrome, yet recent studies suggest HSCT may also be useful to correct the hematological phenotype in children and is indicated in transfusion-dependent patients.
A team of European researchers conducted an analysis to determine survival outcomes in patients with DBA who underwent allogeneic HSCT. Data was collected from 70 children with DBA (<18 years; 44 males) who were registered in Germany or France between 1985 and 2017.
Primary outcomes included engraftment, cumulative incidence of acute graft-versus-host disease (aGVHD) and chronic graft-versus-host disease (cGVHD), probability of overall survival (pOS), and the probability of cGVHD-free survival (cGFS).
Median age at HSCT was 5.5 years, and 26% of patients were aged 10 years or younger at the time of transplantation. A large number of transplantations (64%) were performed from an MSD and most procedures were performed after 1999 (73%). All patients achieved primary engraftment.
The cumulative incidence of grade 2 to grade 4 and grade 3 to grade 4 aGVHD was 24% and 7%, respectively. Furthermore, the cumulative incidence of cGVHD was 11%. No significant difference in the incidence of aGVHD comparing MSD and UD HSCT was observed. Over time, the probability of cGFS (87%) significantly improved from 68% in years earlier than 2000 compared with 94% in 2000 and later (P <.01). cGFS was comparable for patients who received a transplant from either a MSD or an unrelated donor (UD). However, after 1999, no severe cGVHD or deaths were reported following MSD-HSCT, whereas the cGFS for 24 patients transplanted from an UD was 87%. The change of cGFS in patients transplanted at a younger age compared with older patients (<10 years: 90% vs 10-18 years: 78%) was not statistically significant.
Study limitations included the inability to fully analyze the role of ATG and ATG dosing due to the retrospective nature of the study, the lack of availability of genetic testing for all of the patients, and the small sample size of patients between the ages of 10 to 18 years.
“In summary, these data indicate that HSCT is efficient and safe in young DBA patients and should be considered if a MSD or matched UD is available. HSCT for transfusion dependency only must be critically discussed in older patients,” the authors concluded.
Strahm B, Loewecke F, Niemeyer CM, et al. Favorable outcomes of hematopoietic stem cell transplantation in children and adolescents with Diamond-Blackfan anemia. Blood Adv. 2020;4(8):1760–1769.