Outcome of childhood acute lymphoblastic leukemia treatment in a single center in Brazil: A survival analysis study

BACKGROUND Acute lymphoblastic leukemia (ALL) is the most common neoplasm in childhood. The probability of current overall survival (OS) is around 90% in developed countries. There are few studies that demonstrate the results in Brazil. AIM This work aims to analyze the results of children with ALL treated at a single institution in Rio de Janeiro. METHODS AND RESULTS Retrospective analysis survival study of a cohort of childhood ALL patients treated in Hemorio. Kaplan-Meier and log-rank methods were used for the analysis of OS and events-free survival (EFS) and the Cox proportional hazards regression model for multivariate analysis. The probability of OS and EFS at 6 years was 52% and 45%. The probability of OS and EFS in 6 years for patients aged 10-17 years was 31% and 28% and for the younger was 65% and 55%, respectively (p < .001). A probability of OS and EFS in 6 years for patients with more than 100 000 leukocytes/mm3 at diagnosis was 19% and 16% and those with less than 100 000 were 62% (p = .007) and 55% (p = .008). Those who received less than 10 doses of native Escherichia coli asparaginase had a probability of OS and EFS in 6 years of 27% and 21% and those who received at least 10 doses were 74% and 65% (p < .001). CONCLUSIONS The presence of a high number of adolescents and high-risk patients, as well as many patients who discontinued the use of asparaginase or any substitute led to a lower probability of OS and EFS in our cohort.