The Outcome of Modified St. Jude Total XV Protocol in Turkish Children with Newly Diagnosed Acute Lymphoblastic Leukemia: A Single-Center Retrospective Analysis.

ABSTRACT

Objective: This study examines the prognostic factors and outcomes of Turkish children with newly diagnosed acute lymphoblastic leukemia (ALL) who were treated with Modified St. Jude Total XV Protocol, which was modified by adding high-dose methylprednisolone (HDMP) before induction in the original protocol. Materials and Methods: A cohort of 183 newly diagnosed ALL patients aged 1-18 years received Modified St. Jude Total XV Therapy between January 1, 2008 and January 30, 2016. HDMP was administered for 7 days, with randomized doses at 10 or 20 mg/kg/d, tapered during the subsequent 7 days to 5 and 10 mg/kg/d, followed by 2 mg/kg/d for 2 weeks. Absolute blast count in peripheral blood and minimal residual disease (MRD) in bone marrow were assesses at the end of the initial HDMP treatment (Day 7). MRD in the bone marrow was measured on day 15 and at the end of the induction period. These patients were followed until July 15, 2019. Results: The five-year event-free (EFS) and overall survival (OAS) rates for all patients were 85.6±2.6% and 89.2±2.3%, respectively. The steroid good responder rate (<1 000/mm3 absolute blast count in peripheral blood on Day 7) was 88%, with 97% of children achieving complete remission post-induction. No significant differences were observed between the two groups in survival rate and infection frequency. EFS and OAS correlated with initial leukocyte count, age 10-18 years at diagnosis, CD20 positivity at diagnosis, and gram-negative bacterial infection during remission induction. Conclusion: The notable response rates on day 7 and 15, along with encouraging EFS and OAS outcomes with Modified St. Jude Total XV in childhood ALL patients underscore the early and high response effect of HDMP. Short-term HDMP can be initiated at the onset of induction, administered at 10 mg/kg/day for the initial 7 days, aiming to minimize potential side effects.