Outcomes of Adolescents and Young Adults With Acute Myeloid Leukemia Treated in a Single Latin American Center.

INTRODUCTION: The outcomes for adolescents and young adults (AYAs) with acute myeloid leukemia (AML) have been poorly characterized in Hispanics in low- to middle-income countries. The results are influenced by biologic and socioeconomic factors. The clinical paths for AYA patients with AML are reported.

PATIENTS AND METHODS: A retrospective analysis of AYA and pediatric AML patients aged 1 to 39 years during 2003 to 2016 from a single reference center in Northeast Mexico treated with a 7+3 standard protocol was performed. The 5-year overall survival (OS) and event-free survival (EFS) were estimated using Kaplan-Meier analysis. The hazard ratios for relapse and death were estimated using a Cox regression model. The patients with promyelocytic leukemia were analyzed separately.

RESULTS: The study included 110 non-PML AML patients, 39 children and 71 AYAs. No difference in complete remission was found (P = .446), although the overall response rate was greater in the children (87.2% vs. 69% in AYAs; P = .034). The 5-year EFS rate was 33% for the children versus 9.3% in the AYAs at a median follow-up of 22 and 9 months, respectively (P = .008). The 5-year OS rate was 51% in the children and 22% in the AYAs (P = .001). Of the 44 AYAs with complete remission, 29 (65%) developed a relapse. Of the 39 children and 71 AYAs, 20 children (51.3%) and 21 AYAs (29.6%) underwent transplantation (P = .024). Patients with refractory disease had a 1-year OS rate of 14.4%. Older age (hazard ratio [HR], 2.55; P = .002) and white blood cell count > 50 × 109 /L (HR, 1.79; P = .023) were significant for death, and transplantation was protective (HR, 0.57; P = .023).

CONCLUSION: Low EFS and OS rates were found for AML patients in the AYA group. To improve survival rates, intensified chemotherapy regimens and early hematopoietic stem cell transplantation are needed.