Influence of initial treatment delay on overall survival and event-free survival in childhood acute lymphoblastic leukemia

Abstract

Background Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. Initial treatment delay is a modifiable prognostic factor that significantly affects overall survival (OS) and event-free survival (EFS) of childhood ALL in high-income countries. Nevertheless, the effect of delayed initial treatment in low-middle income countries had not been determined. Objective To analyze relationships between initial treatment delay with overall survival and event-free survival in children with ALL. Methods A retrospective study was conducted in children aged < 18 years newly diagnosed with ALL L1 and L2 from January 2013 until December 2018 at Dr. Sardjito Hospital, Yogyakarta. Initial treatment delay was defined as a time interval of more than 3 days between diagnosis and treatment. The outcomes of the study were OS and EFS. Negative events were defined as remission failure, re-lapse, dropping out, and death. Overall survival (OS) and event free survival (EFS) were analyzed by Kaplan-Meier and log-rank tests. Results Of 341 subjects, 188 (55.5%) underwent delayed initial treatment. There were no significant relationships between initial treatment delay and OS (HR 0.845; 95%CI 0.548 to 1.302; P=0.445) or EFS (HR 0.937; 95%CI 0.689 to 1.275; P=0.971). Multivariate analysis revealed that age was an independent prognostic factor for both OS (P<0.001) and EFS (P<0.001). Conclusion Initial treatment delay is not associated with OS or EFS. Age is an independent predictor for both OS and EFS.