Outcomes and survival predictors of Latin American older adults with acute myeloid leukemia: Data from a single center.

Introduction: Acute myeloid leukemia (AML) is most commonly presented in older adults; however, it appears 10 years earlier in Latin American countries. Clinical evolution in older adults from this populations has not been characterized. We analyzed outcomes and survival predictors.

Methods: Patients ≥ 55 years old diagnosed with AML at a hematology referral center from 2005 to 2020 receiving intensive chemotherapy (IC), low-dose cytarabine (LDAC) and best supportive care (BSC) were included. Survival analysis included the Kaplan-Meier and Cox models and the cumulative incidence of relapse (CIR).

Results: Seventy-five adults were included and the overall survival (OS) was 4.87, 1.67 and 1.16 months, using IC, LDAC and BSC, respectively. The IC led to a higher OS (p < 0.001) and was a protective factor for early death, at a cost of more days spent hospitalized and more non-fatal treatment complications; non-significant differences were found between the LDAC and BSC. Eight (10.7%) patients underwent hematopoietic cell transplantation, with a higher OS (p = 0.013). Twenty (26.7%) patients achieved complete remission; 12 (60%) relapsed with a 6-month CIR of 57.9% in those < 70 years old vs. 86.5% in those ≥ 70 years old, p = 0.034. Multivariate analysis showed the white blood cell count (WBC) and IC had a significant impact on the patient survival, whereas chronological age and the Charlson comorbidity index (CCI) did not.

Conclusion: AML in low-middle income countries demands a different approach; the IC improves survival, even with a high incidence of relapse, and should be offered as first-line treatment. Eligibility criteria should include WBC and a multidimensional evaluation. The age per se and the CCI should not be exclusion criteria to consider IC.