Health system and epidemiological determinants of mortality in acute lymphoblastic leukemia in the Brazilian Amazon

BackgroundAcute lymphoblastic leukemia is the most common childhood malignancy; however, survival remains highly heterogeneous across regions, particularly in low- and middle-income settings. In geographically vulnerable areas such as the Brazilian Amazon, structural barriers related to health system organization, centralization of specialized services, and continuity of care may substantially influence treatment trajectories and mortality. This study aimed to examine health system and epidemiological determinants of mortality among patients with acute lymphoblastic leukemia in Amazonas, Brazil. MethodsThis retrospective cohort study included 393 patients diagnosed with acute lymphoblastic leukemia between 2016 and 2021 at the state referral center for hematologic diseases in Amazonas, Brazil. Sociodemographic, clinical, laboratory, and health system-related variables were analyzed. Multivariate logistic regression models were used to identify factors associated with mortality. Spatial analyses described the geographic distribution of cases, and overall survival was evaluated using Kaplan-Meier curves. ResultsThe cohort was predominantly pediatric, with a substantial proportion of adolescents and young adults. Most patients presented with high-risk clinical and laboratory features at diagnosis. Mortality occurred in 48.5% of patients and was strongly associated with age at diagnosis, with higher odds of death among adolescents, young adults, and individuals aged 51-60 years. Geographic concentration of specialized services and treatment-related trajectories were closely linked to survival patterns. ConclusionMortality from acute lymphoblastic leukemia in the Brazilian Amazon remains high and is primarily influenced by age-related vulnerability and health system factors rather than baseline sociodemographic characteristics. These findings underscore persistent regional inequalities in access to specialized care and highlight the need for health system strengthening to improve cancer survival in geographically vulnerable settings.