Heme Flashcards
What FISH tests do you have to check for DLBCL and what defines a double or triple hit lymphoma?
What other odd immunomarker to you check in DLBCL and why?
What should you check if the patient is really old?
1) c-MYC rearrangement
2) Bcl-2 rearrangement
3) Bcl-6 rearrangement
You MUST have a c-MYC rearrangement, and then 1 other for double hit, and both others for triple
Order CD30 IHC because it there is a targeted therapy against it that could be used if +.
If really old, check EBER - reclassify as EBV+ DBCL of elderly (worse prognosis)
What are the features useful to distinguish SLL from MCL on a small biopsy?
SLL- 1) dim light chain expression, 2) dim CD20, 3) FMC7 neg
MCL- 1) bright light chain expression, 2) bright CD20, 3) FMC7 pos, and cyclin D1
What does zap 70 expression mean (in terms of b-cell phenotype and clinically)?
zap70 + means IgH is still unmutated (non G.C. Type or pre GC) – worse clinical course only in SLL if > 30% cells are +
Zap70 neg means GC type (mutated IgH)
Characteristic features and immunophenotype for hairy cell leukemia?
Splenomegaly, pancyropenia, cd11c, 25, cd103
Annexin1 in tissue sections work also
TRAP cytochemical stain is quite specific!!
Diagnostic test is BRAF V600E mutation!!!!! Specific!!
For lymphomatoid granulomatosis: Epidemio (age, sex, sites) Gross fts and distribution Histology DDx
It is an angiocentric and angiodestructive B cell lymphoproliferative disorder that is driven by EBV (Grading based off of amount of large atypical B cells that are EBV +)
M>F, most frequent in young adults (30-40), immunosuppressed (associated with Wiscott Aldrich), >90% w/ Lung inolvement > kidney > brain = liver = skin
Multifocal, multinodular, bilateral, often with lots of necrosis
angiocentric and angiodestructive (often with lymphocytic vasculitis) polymorphous infiltrate that is MOSTLY reactive T cells, scattered p.c.s and histiocytes
Variable proportions of larger, atypical B cells hilited by EBER (proportion determines grade - 50/HPF grade 3)
DDx - extranodal NKcell lymphoma, nasal type (also angiodestructive and EBV associated, but also expressed CD56, and the neoplastic cells are CD3/4+ b/c they are T cells, not B cells like in LYG)
Note - they can be CD30 + so it should be in the differential of an anaplastic large cell lymphoma and Hodgkin!!
What is the unique ftr in the marrow aspirates of AML with inv(16)?
immature eosinophil precursors with mixed basophilic and eosinophilic granules
Describe the Hans Algorithm for DLBCL
Check CD10 first – if +, it is GC type
if negative –> Bcl-6 – if (-) then it is NGC type
if positive –> MUM-1 – if + NGC type, if (-) then GC type
Cleaved lymphocytes in the PBL make you think of what?
pertussis infection
cleaved lymphocytes in tissue = follicular lymphoma
What genes and lymphomas correspond to the following translocations:
t(11;14)(Q23;Q32) t(14;18)(Q32;Q21) BCL6 REARRANGEMENTS MYC REARRANGEMENTS t(11;18)(Q22;Q21) t(9;14)(P13;Q32) t(2;5)(P23;Q35) DUSP22 REARRANGEMENTS
t(11;14)(Q23;Q32); CCND1-IGH
- Mantle cell (cyclinD1 - IgH), Plasma cell neoplasms
t(14;18)(Q32;Q21); IGH-BCL2
- Follicular lymphoma (bcl-2 -IgH), DLBCL
BCL6 REARRANGEMENTS
- Follicular lymphoma, DLBCL
MYC REARRANGEMENTS
- Burkitt, DLBCL
T(11;18)(Q22;Q21); BIRC3-MALT1
-Marginal Zone of MALT (not seen in nodal MZL) —> The presence of this indicates resistance to antibiotic therapy
T(9;14)(P13;Q32); PAX5-IGH
- Nonspecific B cell lymphoprolierative neoplasms (basically can be seen in any B cell lymphoma)
T(2;5)(P23;Q35); ALK-NPM1
- Anaplastic large cell lymphoma, ALK + Large B cell lymphoma
DUSP22 REARRANGEMENTS
- ALK (-) Anaplastic large cell lymphoma
In working up a low grade B cell lymphoma, what are the main markers to get, and what do they indicate?
CD5 - + in CLL/SLL and Mantle cell (not low grade)
CD10 - + in follicular and Burkits and some DLBCL (Burkit and DLBCL not low grade)
CD23 - + in CLL/SLL (in follicular it will show a FDC network)
FMC7 - + in all B cell lymphomas, but is negative in CLL/SLL
Zap70 - if + in >30% of cells by flow in CLL/SLL, it portends a worse prognosis
Describe the different parts of the lymph node follicle and they’re the cell phenotypes. Include the lymphomas that arise from these.
center is germinal center (bcl6 +, bcl2-, CD10+) - Burkitt lymphoma has this phenotype
Next out is Mantle layer (these are naive B-cells waiting for antigen)
Next out is marginal zone (these are terminally differentiated B-cells after the GC)
What do you need to know about hairy cell variant?
Histology resembles hairy cell, but there is HIGH wbc count, and lack of cd25, and 103
Responds poorly to therapy for hairy cell.
No specific cytogenetic abnormality
CAN express cyclin d1, but NOT assoc with t(11;14)
Hide Answer
What are the 2 situations in which the Bcl2 is helpful?
1) reactive (neg) vs follicular lymphoma (pos)
2) Burkitt lymphoma (neg - makes sense b/c GC phenotype) vs. DLBCL (pos)
What are the only CD5+ B cell lymphomas?
CLL/SLL
Mantle cell
DLBCL! can also be CD5+
!rarely, rarely marginal zone also!
