Acute Lymphoblastic Leukaemia (ALL)
N.B. Most common leukaemia in children
This is where there's uncontrolled proliferation of the lymphoid progenitor cell, which leads to lots of early lymphoid precursor cells replacing the normal haematopoietic cells of the bone marrow and infiltrating different organs. It leads to Pancytopenia (anaemia, leukopenia, thrombocytopenia).
N.B. Acute = Immature WBCs proliferating. Chronic = Mature WBCs proliferating.
Presentation
Failure to thrive
S+S of bone marrow failure
Anaemia – Fatigue, Pallor
Neutropenia – Recurrent infections
Thrombocytopenia – Petechiae, Abnormal bruising, Unexplained bleeding
S+S of organ infiltration
Bone pain
Lymphadenopathy
Hepatosplenomegaly
Investigations
FBC!
Blood film, which will show blast cells
Bone marrow and Lymph node biopsy
N.B. ALL is also associated with the Philadelphia chromosome (t(9;22) gene translocation), where it is a poor prognostic marker.

Management
Chemotherapy
Bone marrow transplant
There's around an 80% cure rate in those started on treatment!