Overview

Immunophenotyping is a laboratory technique used to identify specific types of leukemia cells based on the proteins (antigens) expressed on their surface. It helps distinguish acute lymphoblastic leukemia (ALL) from acute myeloid leukemia (AML) and subtypes within them. Peripheral blood (P.B.) can be used if there are circulating blasts, otherwise bone marrow is preferred.

Purpose / Clinical Use

• Classify leukemia type and subtype.
• Guide treatment decisions.
• Monitor minimal residual disease (MRD).
• Prognostic assessment.

Risk Assessment

• Sample collection risks: Minimal; involves routine venipuncture.

• Patient-related risks: Mild bruising or discomfort at the puncture site.

• Laboratory risks: Low; standard biohazard precautions applied.

Normal Range 

• Normal peripheral blood: No significant population of blasts; normal distribution of lymphoid and myeloid cells.

• Leukemia: Presence of abnormal blasts expressing lineage-specific markers.

  • B-ALL: CD19+, CD10+, CD22+, TdT+

  • T-ALL: CD3+, CD7+, CD5+, TdT+

  • AML: CD13+, CD33+, CD117+, MPO+

(Exact patterns vary by subtype and lab panel.)

Interpretation

• Positive for lineage-specific markers: Confirms leukemia type.

• Aberrant marker expression: Can indicate mixed-lineage leukemia or prognosis.

• No abnormal population: Leukemia unlikely or very low-level disease; may need bone marrow evaluation.

Sample Type

• Primary: Peripheral blood (P.B.)

• Alternate: Bone marrow aspirate (if blasts are low in blood)

• Collection: EDTA anticoagulated tube