Miscellaneous II Flashcards
CD4:CD8 ratio
BM not good sample for this- rather PB is optimal
Causes of dyserythropoiesis
NK/T cell neoplasm
LGL neoplasm
Aplastic anemia
Hypocellular MDS
Should see increased blasts (otherwise, don’t flat out call it!)
Could be an evolving aplastic anemia
Monoblasts by flow
Show decreased expression of CD14 and CD36 (also CD64)
AML from MDS morphology
Often see a less packed marrow than de novo AML- still see background erythroid islands
Burkitt lymphoma in HIV
Can look plasmacytoid
Vacuoles in Burkitt
Fat- oil red O positive
Vacuoles in Erythroleukemia
Glycogen- PAS positive
c-MYC threshold IHC
50-70%
Look for Parvovirus when you see…
Anemia and erythroid hypoplasia
Percent dysplasia to call
at least 10%
Hematogones in MDS
decreased
MDS comment:
These findings (dyserythropoiesis) are non-specific, and may be seen in:
- nutritional deficiency
- meds
- infection
- autoimmune
- low grade MDS
Percent hypersegmented PMNs to call
Greater or equal to 6%
Granulocytic finding in Folate/B12 deficiency
giant band
Assessing marrow cellularity
Better to do on a bad core than on a good clot section (clot section compresses fat and falsely increased cellularity)
Left-shifted erythroids vs lymphoblasts
left-shifted erythroids= more cytoplasm
lymphoblasts= less cytoplasm
MPN with lots of mature neutrophils, lacking myelocyte bulge
Consider PMF, atypical CML, and CNL
Cat-scratch lymphadenitis
Stellate microabscess formation
if inguinal LN, cannot distinguish from lymphogranuloma venereum
Plasma cell neoplasm oral cavity
ALWAYS remember to order HHV8 and EBER
NLPHL architecture
If see PTGC but no effacement- Do NOT call NLPHL (without effacement)
Marrow s/p rituxin
can see T cells in the marrow (see Foucar paper)
Increased CD8 T cells
Can see in reactive conditions too (throws off CD4:CD8)
Burkitt
- paucity of small lymphs
- “jigsaw” appearance
- DDx: ALL, blastic mantle cell, myeloid sarc
Lymph node with histiocytes and/or granulomas
Aside from the usual AFB/GMS, consider also doing a PAS to look for Whipple’s disease (PAS+)
Amyloidoma
AKA nodular amyloid:
- asymptomatic elderly with nodule on chest xray w/o evidence of systemic disease
- good prognosis, dont often progress to lymphoproliferative disorders
- well circumscribed amyloid, often with T lymphocytes and plasma cells
- granulomatous reaction to amyloid common, often calcification and ossification
Nodular LP HL
LP cells are positive for BCL6, EMA, OCT2, BOB1; negative for CD15 and CD30 (BUT you can see CD30 positive large cells that are reactive immunoblasts unrelated to LP cells
Percent IHC positivity for Hans algorithm
30%
“Tumor Stage MF”
Even in the presence of an atypical T cell proliferation with loss of CD7 and CD5, you cannot call MF. This could still be REACTIVE! Need hx of MF to call MF/lymphoma.
IHC for MCL
Should do both cyclin d1 and sox-11 because sox11 can also be positive in burkitt, lymphoblastic lymphoma, and blastoid variant of mcl (dont use it to distinguish these)
Bcl2
Expressed in all low grade cell lymphomas- careful with nodular pattern of mcl
FL by flow
Dim CD19
FL marrow involvement
Almost always see by morphology. Due to paratrabecular location, the aspirate for flow may miss it, but usually the core will show.
Buffy coat M:E
Can be falsely increased bc erythroids cluster together
Disrupted cells on aspirate
Tend to be erythroid. Thats way you actually over estimate the M:E a little on aspirate vs core
Weird FL
If FL starts expressing T cell markers like CD5, it must have either CD10 or t(14;18) to call it. Otherwise think about mantle cell or marginal zone. Also CD11c very rare in FL, more common in MZL
Atypical CLL
???
Iron stain helps you
Can tell erythroid precursors vs plasma cells; also helps you tell the M:E ratio better
Very dysplastic looking mature PMNs (abnormal lobation, hypogranularity- really ugly), increased blasts and left shift on marrow
Can be due to GCSF- do not call high grade MDS
Monocyte/macrophage/histiocyte associated markers
Lysozyme, CD14, CD68
Hb H inclusions
- seen 3 gene deletion alpha (Hb H) and may be positive in 2 gene deletion (alpha thal minor)
- whole blood with brilliant cresyl blue causes oxidation and ppt of Hb h
- golf ball pattern