The Survival of Childhood Acute Lymphoblastic Leukemia and its Related Factors Using Competing Risks Model: A Retrospective Study from 2011 to 2019 in Northwestern Iran

Abstract

Background: We aimed to evaluate the survival rate and define the prognostic factors in children with acute lymphoblastic leukemia (ALL). Method: In this retrospective study, the data were extracted from the medical records of 176 children with ALL who referred to Motahari Hospital in Urmia from 2011 to 2019. Endpoints of overall survival study were event-free survival, disease-free survival, and recurrent mortality. Overall survival and disease-free survival were the time from diagnosis to death of any cause or recurrence. Event-free survival time was calculated as the distance from the date of diagnosis to the date of the last prevention with the first event. Non-recurrent mortality included all non-recurrent deaths. Data analysis was performed using a cause-specific hazard model. Results: The mean age of the patients was 5.61 ± 3.56 years and the median of diagnosis of ALL to death was 3.47 ± 2.61 years. The 1-year, 3- year and 5-year probability of survival were 83.1%, 75.10%, and 68%, respectively. Sex, hemoglobin level, and hepatosplenomegaly were significant in univariate and multivariate analysis (P < 0.05). Conclusion: The competing risks model was applied to identify the risk factors for all causes of death. The factors affecting the survival rate of patients in the model can be employed in making clinical decisions and proposing therapeutic protocols. Furthermore, it reduces the duration of response to therapy, thereby decreasing the rate of mortality in children.

Keywords

• acute lymphocytic leukemia
• cause-specific hazards
• childhood cancer
• competing risk