[Effect of Chemotherapy Course Delay on the Relapse of Paediatric B-cell Acute Lymphoblastic Leukemia].

ABSTRACT

OBJECTIVE: To investigate the effect of course delay of CCLG-ALL-2008 regimen on the relapse of paediatric B-cell acute lymphoblastic leukemia (B-ALL) patients. METHODS: Paediatric B-ALL patients newly diagnosed and treated with CCLG-ALL-2008 regimen in the Children's Hospital of Soochow University from January 2011 to December 2014 were retrospectively analyzed to clarify the relationship between chemotherapy course delay and relapse, and explore the causes of course delay which led to relapse. Patients were followed up until July 2019. RESULTS: The correlation between treatment delay (number of weeks) and relapse rate was statistically significant (P=0.034), and hazard ratio indicated that longer than 4 weeks had a significant effect. The effect of positive minimal residual disease (MRD) (1×10-4≤MRD≤1×10-2) at the 12th week on the relapse rate was also statistically significant (P=0.041). Among the causes of treatment delay, the effect of myelosuppression on the relapse rate was statistically significant (P=0.01). CONCLUSION: Treatment delay exceeding 4 weeks, positive MRD at the 12th week, and myelosuppression are independent prognostic factors for relapse.