|L1||Lymphoblasts with uniform, round nuclei, and scant cytoplasm
Nucleoli are not prominent.
|L2||More variable lymphoblast and cytoplasm is abundant.
Nucleoli are large and may see one or more nucleoli.
|L3||Lymphoblasts with fine nuclear chromatin and blue to deep blue cytoplasm that contains vacuoles.
Lymphoblast is large and has prominent nucleoli and these are one or more than one.
|M1||Undifferentiated myeloblastic. No cytoplasmic granulation
Also called acute myeloblastic leukemia with no differentiation (20 %)
|M2||Differentiated myeloblastic cells and sparse granules in the cytoplasm
Also called AML with maturation
|M3||Acute Promyelocytic Leukemia
Granules are typical of promyelocytic morphology (5 to 10 %)
|M4||Acute Myeloid Monoblastic Leukemia
The mixed population of myeloblastic and monocytic morphology (15 to 20 %)
|M5||Acute Monoblastic Leukemia
Pure monobasic morphology (10 )
Predominantly immature erythroblast morphology, sometimes megaloblastic appearance ( 5)
|M7||Acute Megakaryoblastic leukemia
Megakaryocytic Cells with shaggy borders that may show some budding ( 1%)
|Characteristic Features||Acute Myelocytic Leukemia||Acute Lymphocytic Leukemia|
|Origin of the cells||Myeloid series cells||Lymphoid series cells|
|Features of Blast cells||Large is size,||Small in size|
|Cytoplasm is moderate||Cytoplasm is scanty|
|Chromatin is fine and lacy||Chromatin is dense|
|Nucleoli are prominent and >2||Nucleoli are indistinct and <2|
|Sudan black and peroxidase||Positive||Negative|
|Bone marrow||A mixed population of myeloid cells and blast cells||Mainly blast cells and very few WBCs or RBCs|
|Leukocyte Alkaline phosphatase (ALP)||Positive (differentiate CML from the leukemoid reaction.||Negative|
|Periodic Acid-Schiff (PAS)||Positive in Erythroblast in M6 leukemia||
Positive (block patterns) in L1 and L2
Negative in L3