Hi Bemish,

Thanks for the query.

Blast cells are the precursor cells which would divide into two different types of cells and undergo maturation in bone marrow and these matured cells will circulate in the peripheral blood. Normally, it is very rare to find blast cells in Peripheral blood.

In malignancy, as there would be excess production of blood cells converted to Blast cells and would not undergo maturation in the bone marrow due to limited resources like Growth factors and so it can be detected in peripheral blood smears which is considered as a sign of abnormality.

Blast cells can be detected in Blood smears in majority of cases of malignancy and other systemic abnormalities but the Bone marrow examination is considered to be a confirmatory and diagnostic investigation. So is preferred to be done along with Peripheral Blood smears and also is helpful in considering the future line of treatment.

Hope this answers your query. In case of any doubts, I am available for the follow ups.,

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