TREATMENT OUTCOMES OF HIGH-RISK PEDIATRIC ALL PATIENTS UNDERGOING INTENSIFIED CHEMOTHERAPY PROTOCOLS

Abstract

Background: High-risk acute lymphoblastic leukemia (ALL) in children is associated with an increased likelihood of induction failure, relapse, treatment-related complications, and mortality. Objective: To evaluate treatment response, treatment-related toxicities, relapse, survival outcomes, and prognostic factors among children with high-risk ALL treated with intensified chemotherapy protocols. Methods: This retrospective observational study was conducted in Pediatrics department of Mayo Hospital Lahore from January 2021 to December 2021. Data regarding demographic characteristics, immunophenotype, complete remission following induction, end-induction MRD status, treatment-related toxicities, relapse, mortality, event-free survival (EFS), and overall survival (OS) were obtained from medical records. Results: The mean age of the patients was 8.2 ± 3.6 years, and 52 (61.2%) were male. B-cell ALL was diagnosed in 68 (80.0%) patients, whereas 17 (20.0%) had T-cell ALL. Complete remission after induction chemotherapy was achieved in 72 (84.7%) patients. End-induction MRD negativity was documented in 60 (70.6%) patients, while 25 (29.4%) remained MRD positive. Mucositis was the most frequent treatment-related toxicity, occurring in 40 (47.1%) patients, followed by febrile neutropenia in 32 (37.6%), severe infections in 24 (28.2%), and hepatotoxicity in 15 (17.6%). During follow-up, 15 (17.6%) patients experienced relapse and 8 (9.4%) died because of disease progression or treatment-related complications. The estimated 3-year EFS and OS were 74.1% and 82.4%, respectively. Conclusion: Intensified chemotherapy protocols achieved encouraging remission and survival outcomes in children with high-risk ALL. However, treatment-related toxicities remained frequent.