Acute lymphoblastic leukaemia under 2 years.

Area of Science:

• Pediatric Oncology
• Hematology
• Leukemia Research

Background:

• Acute lymphoblastic leukemia (ALL) is a significant childhood cancer.
• Outcomes for infants diagnosed with ALL are not well-established.
• Understanding disease presentation and natural history in young children is crucial for treatment optimization.

Purpose of the Study:

• To assess the presenting features and natural history of acute lymphoblastic leukemia in children under two years of age.
• To compare outcomes in infants and young children with older children diagnosed with ALL.
• To identify specific challenges and toxicities in treating very young ALL patients.

Main Methods:

• Retrospective analysis of 48 children diagnosed with ALL under two years of age.
• Categorization into two groups: under 1 year (Group 1) and 1-2 years (Group 2).
• Comparison with a control group of 348 children aged 2-14 years (Group 3).

Main Results:

• Children under 1 year (Group 1) showed higher rates of null-cell ALL, elevated white blood cell counts, hepatosplenomegaly, and increased central nervous system (CNS) relapse.
• Disease-free and overall survival in children aged 1-2 years (Group 2) were comparable to older children (Group 3).
• Group 2 experienced a significantly higher CNS relapse rate compared to Group 3.
• Neurological toxicity from methotrexate and radiation therapy was prevalent in children under two years.

Conclusions:

• Infants under one year with ALL have a particularly poor prognosis.
• Children aged 1-2 years have a similar prognosis to older children but require strategies to mitigate higher CNS relapse rates.
• Novel approaches to CNS prophylaxis are essential to reduce both CNS disease incidence and treatment-related toxicity in young ALL patients.