Immnophenotypic markers in AML
From haematologyetc.co.uk
Table: Marker patterns that allow definite diagnosis of acute myeloid leukaemia; | |
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Pattern 1: A myeloid lineage-defining marker pattern is present and No lineage-defining markers of T or B cells are present. | |
MPO | MPO is the only "lineage-defining" marker of AML. MPO is expressed in around 80% of cases of AML and in the absence of any other lineage defining features detection of MPO expression allows a diagnosis of AML to be made (see notes). |
Pattern 2: At least two myeloid lineage-associated markers are present and There are no lineage defining markers of T or B cells and No more than one: T-cell or B-cell lineage-associated markers are present | |
CD38 | Variable expression in AML cases (around 20%) compared with higher expression on lymphoid blasts (particularly T-ALL). CD38 may identify leukaemia initiating cells and is a potential therapeutic target. |
HLA-DR | Expressed in around 70-80% of AML cases, but also frequently expressed in ALL. The most valuable aspect of HLA-DR is the absent or weak expression in APL when compared with reactive myeloid cells. |
TDT | TdT is more often associated with ALL, but the expression by around 20% of AML cases is well recognised, particularly in more primitive forms of the disease. |
CD7 | Regarded as a pan-T-cell marker expressed throughout T cell development, CD7 is also expressed frequently as an "aberrant" marker in AML where it is best regarded as a marker of their primitive nature |