A bone marrow differential shows 20% blasts with flow cytometry showing CD10+, CD19+, CD22+ and CD13/CD33-. Which disease is most compatible?

A bone marrow differential shows 20% blasts with flow cytometry showing CD10+, CD19+, CD22+ and CD13/CD33-. Which disease is most compatible?

• A. AML
• B. ALL
• C. CML
• D. CLL

Answer: (B)

Immunophenotyping with flow cytometry is used to identify the lineage of leukemia blasts. The blasts express CD19, CD22, and CD10, which are classic B-cell–lineage markers, with CD10 (CALLA) commonly seen in precursor B cells. The absence of myeloid markers like CD13 and CD33 supports a non-myeloid (lymphoid) origin. While 20% blasts can be seen in various settings, the strong B-lineage profile fits precursor B-cell acute lymphoblastic leukemia rather than AML. CLL would typically show mature B-cell markers such as CD5 and CD23 with fewer or no blasts, and CML would present with a different myeloid/phenotypic pattern and often BCR-ABL positivity.

Immunophenotyping with flow cytometry is used to identify the lineage of leukemia blasts. The blasts express CD19, CD22, and CD10, which are classic B-cell–lineage markers, with CD10 (CALLA) commonly seen in precursor B cells. The absence of myeloid markers like CD13 and CD33 supports a non-myeloid (lymphoid) origin. While 20% blasts can be seen in various settings, the strong B-lineage profile fits precursor B-cell acute lymphoblastic leukemia rather than AML. CLL would typically show mature B-cell markers such as CD5 and CD23 with fewer or no blasts, and CML would present with a different myeloid/phenotypic pattern and often BCR-ABL positivity.