Leukemias
Acute Leukemia
● ↑ rate of clonal proliferation of blast cells, reduced apoptosis, lack of
differentiation
● Most aggressive form of hematopoietic malignancies. Sudden onset and rapid
progression
● Marrow blast cells indicate: 20% diagnosis, 4% remission/relapse, 60% infiltration, >80%
bone marrow failure + (death)
Factor AML ALL
Age Adults (children rarely) Children (adults rarely)
Blood Anaemia, neutropenia, Anaemia, neutropenia,
thrombocytopenia; myeloblasts thrombocytopenia; myeloblasts
and promyeloblasts and promyeloblasts
Morphology Medium to large blasts, more Small to medium blasts, scarce
cytoplasm than lymphoblasts, cytoplasm without granules,
cytoplasmic granules, distinct indistinct or absent nucleoli
nucleoli, Auer rods
Cytochemist Positive peroxidase and Sudan Negative peroxidase and Sudan
ry black, negative TdT black, positive TdT
Extramedull Common in spleen and liver, less Common in lymph nodes, spleen,
ary diseases common in lymph nodes and liver, CNS and gonads
CNS
● AML
○ FLT-3 gene has common translocation between retinoic acid receptor ά
(RARά) gene and promyelocytic lukemia protein (PML) gene. RARά involved
in myeloid differentiation (tyrosine kinase) and PML in suprresion of cell
growth and apoptosis
● ALL
○ High incidence in childhood from 2 hit theory that lymphoid progenitor undergoes
a ‘normal’ mutation after birth
Acute Leukemia
● ↑ rate of clonal proliferation of blast cells, reduced apoptosis, lack of
differentiation
● Most aggressive form of hematopoietic malignancies. Sudden onset and rapid
progression
● Marrow blast cells indicate: 20% diagnosis, 4% remission/relapse, 60% infiltration, >80%
bone marrow failure + (death)
Factor AML ALL
Age Adults (children rarely) Children (adults rarely)
Blood Anaemia, neutropenia, Anaemia, neutropenia,
thrombocytopenia; myeloblasts thrombocytopenia; myeloblasts
and promyeloblasts and promyeloblasts
Morphology Medium to large blasts, more Small to medium blasts, scarce
cytoplasm than lymphoblasts, cytoplasm without granules,
cytoplasmic granules, distinct indistinct or absent nucleoli
nucleoli, Auer rods
Cytochemist Positive peroxidase and Sudan Negative peroxidase and Sudan
ry black, negative TdT black, positive TdT
Extramedull Common in spleen and liver, less Common in lymph nodes, spleen,
ary diseases common in lymph nodes and liver, CNS and gonads
CNS
● AML
○ FLT-3 gene has common translocation between retinoic acid receptor ά
(RARά) gene and promyelocytic lukemia protein (PML) gene. RARά involved
in myeloid differentiation (tyrosine kinase) and PML in suprresion of cell
growth and apoptosis
● ALL
○ High incidence in childhood from 2 hit theory that lymphoid progenitor undergoes
a ‘normal’ mutation after birth
