آزمایشگاه پزشکی پاستور

Definition of Myeloblast:

A)Myeloblast were defined in terms of several nuclear characteristics,including:

1-a high nuclear/cytoplasmic ratio

2-easily visible nucleoli and

3-usually but not invariably,fine nuclear choromatin

4-nuclear shape is variable

B)cytoplasmic characteristics include:

1-variable cytoplasmic basophilia

2-there may or may not be granules or Auer rods but no Golgi zone is detected.

3-The exception to this last observation may be seen in cases of AML with t(8;21) where there may be blast cells with a small distinc Golgi,with or without an Auer rods but with no other features of promyelocyte.

After reviewing all the available bone marrow smear,the IWGM group recommended that:

-Myeloblasts in MDS (WHO in AML) should be classified as agranular or granular.

-the agranular blasts correspond to the type I blasts of the FAB classification.

-Granular blasts are cells that have the nuclearof blast cells but also have cytoplasmic granules.

-These cells will thus include TypeII blasts as defined by FAB,as well as typeIII blasts as defined by Goasguen et al.

-Granular blasts must be distinguished from promyelocytes.