CMML Flashcards
1
Q
Are immunophenotypic abnormalities seen in reactive monocytosis?
A
- yes, but usually limited to one or at most two abnormalities.
2
Q
What are some immunophenotypic abnormalities described in CMML?
A
- Decreased expression of monocytic markers (HLA-DR, CD13, CD15, and CD36)
- Over-expression of CD56
3
Q
What is important to remember about CD56 expression on monocytes?
A
- As the sole abnormality does NOT imply neoplasm
- CD56 can be seen on monocytes in reactive conditions and during marrow regeneration after chemotherapy.
4
Q
What key marker seemed to differentiate CMML monocytes from reactive ones?
A
- CD14
- patients with CMML more likely to have a subset of monocytes expressing decreased or moderate levels of CD14.
- This finding in the presence of 20% or more monocytes in the marrow with one more immunophenotypic abnormality found to be sensitive for CMML vs. reactive monocytosis
5
Q
What does the decrease in CD14 expression on the monocytes likely represent?
A
- likely represents at least some left shift with presence of monoblasts and promonocytes
- IMP: the CD14 clone is important to know because some only mark mature monocytes
6
Q
What other cell population has been noted to be increased in CMML?
A
- plasmacytoid dendritic cells
- Found in the blast gate
- Show expression of bright CD123 and HLA-DR