Erythroid maturation

Proerythroblast

Basophilic erythroblast

Polychromatophilic erythroblast

Acidophilic erythroblast

Reticulocyte

Mature RBC

Erythroid Dysplasia

Myeloid maturation Myeloblast Promyelocyte Myelocyte Metamyelocyte Band Neutrophil

Myeloblast

Promyelocyte

Myelocyte

Metamyelocyte

Mature neutrophil

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Megakaryoblas

Plasma cell

leukemia

Leukemia A disorder characterised by the accumulation of malignant white cells in the BM and PB. Acute leukemia Chronic leukemia

Acute leukemia A malignant disorder in which blasts constitute >20% of the BM cells Classification: Acute Myeloid Leukaemia (AML) Acute Lymphoblastic Leukaemia (ALL) The acute leukaemias are aggressive diseases in which the malignant transformation causes accumulation of early progenitor cells called blasts. They are defined as the presence of >30% blasts in the bm. They are subdivided into AML and ALL depending as to whether the blasts present are myeloblasts or lymphoblasts.

AML FAB classification Acute myeloblastic leukemia ( M0, M1, M2 ) Acute promyelocytic leukemia ( M3, M3v ) Acute myelomonocytic leukemia ( M4, M4Eo ) Acute monocytic leukemia ( M5a, M5b ) Acute erythroleukemia ( M6 ) Acute megakaryocytic leukemia ( M7 ) According to the FAB classification AML is subdivided into 7 different categories, from M1 in which the cells present are very primitive through to the other categories in which the cells show more tendency to differentiate along normal cell lines. In M5 the cells resemble monocytes. In M6 or erythroleukaemia the cells develop along the red cell pathway. The newer classification from the WHO is slightly different in that its not so related to the morphology of the cells as to the aetiology……

Distinguishing AML from ALL Light microscopy AML: Auer rods, cytoplasmic granules ALL: no Auer rods or granules. Flow cytometry Special stains (cytochemistry)

Cytochemistry AML Myeloblastic - SBB, MPO, Chloroacetate Esterase Monoblastic - Non Specific Esterase ALL B lineage – PAS T lineage – Acid Phosphatase

AML-M0

AML-M1

AML-M1

AML-M1 (MPO)

AML-M2

AML-M2 (MPO)

AML-M3

AML-M3 (MPO)

AML-M4E0

AML-M5a

AML-M5b

AML-M5a Cytochemistry NBE

AML-M6

AML-M6

AML-M7

AML-M7 (Dirty Field)

AML-M7 Cytochemistry MPO

AML-M7 (PAS)

CML

ALL-L1

ALL-L2

ALL-L3

CLL

PLL

HCL