Acute Lymphoblastic Leukaemia: Prognostic Features

Key points

• Acute lymphoblastic leukaemia is a malignancy of lymphoid progenitor cells (B or T lineage) causing arrested maturation and proliferation of immature lymphoblasts, leading to bone marrow failure
• Most common childhood cancer; peak age 2–5 years; accounts for ~80% of childhood leukaemias
• Good prognostic factors: FAB L1 subtype, common ALL, pre-B phenotype, low initial white cell count, age 2–10 years
• Poor prognostic factors: age < 2 or > 10 years, male sex, high initial white cell count (> 20 x10⁹/L), T or B cell surface antigens, non-Caucasian ethnicity, presence of Philadelphia chromosome