Most common cancer in children (33% of all malignancies)
Most without cause but increased incidence with paternal age, maternal fetal loss, higher birthweight, familial clusters, and some genetic syndromes (Down syndrome)
3/4 of pediatric<unk> 
5-year survival 75%-80%
Peak incidence 2-5yr old
Usually B lineage
1/5 of pediatric<unk> 
Worse prognosis
More complications (more intense chemo treatment required)
Leukemia 
Leukemias will often involve >1 cell line; other conditions restricted to single line
Leukopenia
Aplastic anemia
Acute myeloid leukemia
Iron deficiency anemia
Myelofibrosis
Viral infection 