Acute Leukemia During the First Six Months of Life: A Population-Based Analysis of Survival by Leukemia Type

Acute leukemia diagnosed during infancy is associated with inferior survival compared with leukemia diagnosed in older children, but outcomes during the first 6 months of life remain poorly characterized.

We performed a retrospective population-based cohort study using the Surveillance, Epidemiology, and End Results (SEER) database to evaluate overall survival among children diagnosed with first primary acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML) during the first 6 months of life. Overall survival was estimated using the Kaplan-Meier method and multivariable Cox regression.

A total of 384 children were included, comprising 197 (51.3%) with AML and 187 (48.7%) with ALL. Children with AML were younger at diagnosis than those with ALL (median age, 1 vs. 3 months; P < .001). Five-year overall survival was 59.8% (95% CI, 52.3%-66.4%) for AML and 42.5% (95% CI, 34.8%-50.0%) for ALL (log-rank P = .014). After adjustment for age at diagnosis, sex, race, and Hispanic ethnicity, AML was associated with a lower hazard of death than ALL (adjusted hazard ratio [HR], 0.57; 95% CI, 0.42-0.78; P < .001). Increasing age at diagnosis independently predicted improved survival (adjusted HR per month, 0.82; 95% CI, 0.75-0.90; P < .001). Despite superior long-term survival, early mortality was more frequent in AML than ALL (14.7% vs. 7.0%; P = .015).

These findings identify age and leukemia type as independent predictors of survival during the first 6 months of life and provide a population-based benchmark for evaluating emerging biologically directed therapies.