Immunophenotyping

Author(s): S. Fruehauf, A. Pitkus
Institution(s): Heidelberg University Medical Centre
Last change of this image collection: 2004/10/01

Immunophenotyping: Immunophenotyping was attempted on a bone marrow specimen, but it was an insufficient specimen. Immunophenotyping was successfully performed on a second fresh bone marrow specimen, a week later. In the forward and side scatter plots, the mononuclear cell populations are well defined. In the electronic gate around the cell populations with characteristic light scatter features, lymphocytoid cells comprising 47% of the total cells, monocytoid cells comprising 3% of the total cells, and granulocytoid cells comprising 51% of the total cells were noted. In the CD45 and side scatter plot is a blast population with low CD45 expression and low side scatter characteristics, comprising 19% of the cells with the exclusion of the red cell precursors which comprise 23% of the cells. In the mononuclear cell gate, this population shows the following phenotype: CD34 -, CD7+, HLA DR -, cCD3+, CD4 -, and TdT+. Myeloid markers were not analyzed. There is a small population of B-Cells, which are CD19+.

Comment on this image collection: A population of >20% of the mononuclear cells express two early t-cell markers and lack the lineage specific myeloid markers. Therefore the diagnosis is a pro T-cell acute lymphocytic leukemia.