NK-lymphoblastic leukemia/lymphoma Flashcards
1
Q
What is the issue with this
disease entity ?
A
- very difficult entity to define
- many of the cases in the literature previously that were CD56 positive have been found to be BPDCN
2
Q
What is true about NK cell
progenitors when they develop ?
A
- they express no specific markers OR they express markers that overlap with T-ALL
- CD7, CD2
- even CD5 can be positive
- cCD3 epsilon
- CD16
- more mature marker of NK cells
- rarel ever expressed in NK cell leukemia
IMP: difficult to distinguish between T-ALL and NK-cell tumors
3
Q
What are other relatively specific markers
for NK cells ?
A
- relatively specific and expressed on NK cell progenitors
- CD94
- CD161
- unfortunately these are uncommonly tested
4
Q
In what circumstance can a diagnosis of NK
lymphoblastic leukemia/lymphoma be considered ?
A
- as of now this is a provisional entity
- can consider this diagnosis IF:
- cells express CD56
- immature T associated markers: CD7, CD2, cCD3
- lack of B and myeloid antigens
- TR and IG genes are in the germline configuration
- BPDCN has been excluded