Allogeneic Hematopoietic Cell Transplantation in Elderly Patients in a Latin American Country: Analysis of 11 Years of Data from the Brazilian Registry SBTMO/CIBMTR.

Abstract

This study analyzed recent changes in the utilization of allogeneic HCT for treatment of acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), and myeloproliferative diseases (MPD) and the survival of HCT recipients ≥60 years of age in Brazil. This retrospective registry study included patients who received a first allogeneic HCT from any donor between 2012 and 2023. Of the 6657 patients, 444 (7%) were 60 years of age or older who received grafts from HLA-matched related (42%) or unrelated (20%) donors or HLA-haploidentical donors (32%). The proportion of HCT recipients 60 years of age or older increased gradually from 3.2% in 2012 to 16% in 2023 mostly due to the increased use of HLA-haploidentical donors since 2018. Overall survival (OS) at day 100 was 77%, and estimated OS at 12 months was 53% (95% CI, 48-58). OS at 12-months was higher for transplants during 2015-2017 (58%) and 2018-2020 (68%) compared to 2012-2014 (45%), but it did not differ for those during 2021-2023 (49%). Mortality with HLA-haploidentical donors (HR 2.35; 95%CI; 1.65-3.34 [p <0.001]) and cord blood donors (HR 4.68; 95%CI,1.29-16.9 [p= 0.01]) was higher than with HLA-matched related donors. Mortality was lower for transplants during the 2015-2020 period (HR 0.57; 95%CI, 0.34-0.96 [0.037]) than for those during 2012-2014.This study revealed a gradual increase in the use of allogeneic HCT in individuals aged 60 years and older in Brazil. While use of haploidentical donor has increased worldwide, its association with increased mortality in elderly population deserves caution.