Leukemia and its classification

Leukemia

•         Definition:

            Leukemia is the malignant neoplasms of hemopoiectic stem cells characterized by diffuse replacement of bone marrow by neoplastic immature hemopoietic cells.

Classification

A)    Acute leukemias:

            Aute myeloblastic leukemia

            Acute lymphoblastic leukemia

B) Chronic leukemia:

            Chronic myeloid leukemia

            Chronic lymphocytic leukemia

                        -B cell leukemia

                        -T cell leukemia

           

Acute leukemias

a) Acute myeloblastic leukemia (FAB Classification):

•                     M0-minimally differentiated acute       myeloblastic leukemia

•                     M1-acute myeloblastic leukemia,         without maturation

•                     M2-acute myeloblastic leukemia, with            granulocytic maturation

•                     M3-acute promyelocytic leukemia

•                     M4-acute myelomonocytic leukemia

•                     M5-acute monocytic leukemia

•                     M6-acute erythroid leukemias

•                     M7-acute megakaryoblastic leukemia

b) Acute lymphoblastic leukemia: (FAB classification)

•         ALL-L1: small uniform lymphoblasts

•         ALL-L2: large varied lymphoblasts

•         ALL-L3: large varied lymphoblas ts with vacuoles (bubble-like features)

	AML	ALL
Auer rod	Present	Absent
N:C ratio	High	high
Nucleoli	3-4	1-2
Chromatin	Less dense	dense
PAS stain	Negative	Positive
MPO	Positive	Negative
Sudan black B	Positive	Negative