Path/Heme Maligs III Flashcards
Name some Ig promoters
IgH (14q32) Ig lambda (22q11) Ig kappa (2p12)
Bcl2 and Bcl6 are overproduced in these neoplasms
Germinal center derived
Cyclin-D1 and Myc are overproduced in these neoplasms
naive B cell neoplasms
Cyclin D3 and Pax5 are overproduced in these neoplasms
memory B cell neoplasms
Where does CLL primarily manifest?
Peripheral blood
Where does follicular lymphoma primarily manifest?
Lymph nodes
Where does Burkitt’s lymphoma primarily manifest?
GI tract
CLL is derived from what type of cell?
Memory B cells (already class switched)
What is a good prognosis in CLL?
13q del only
What is a bad prognosis in CLL?
del(17p) (p53)
Immunophenotype of CLL
Light chain restriction (clonal)
CD5+ (odd but characteristic)
Somatic hypermutation markers
Two other genetic events leading to CLL
Trisomy 12 and del11q
How do smudge cells help predict prognosis of CLL?
> 30% is good
Morphology of CLl
Smudge cells
Pseudofollicular lymph nodes
Small lymphocytes with sparse cytoplasm and mature chromatin
Common presentation of CLL
lymphocytosis in older males with recurrent infections (hypogammaglob)
Common presentation of MCL and what does it mimic closely?
lymphocytosis in older males with recurrent infections (hypogammaglob); mimics CLL
Where does mantle cell lymphoma primarily manifest?
Lymph nodes
What is the key difference between CLL and MCL?
No proliferation centers in MCL
What immunomarkers are helpful in distinguishing CLL from MCL and how so?
CD20+ very strong in MCL, much weaker in CLL
What translocation is common in MCL?
t(11;14) aka (IgH;CyclinD1) which is ALWAYS seen by FISH
What is the key clinical predictor of MCL?
Ki-67 immunostain for mitotic rate
Where do plasma cell neoplasms primarily manifest?
Bone marrow
What are some smear and lab findings of plasma cell neoplasms?
Rouleaux on PB; inc total protein (antibodies)
What would you expect to see on a plasma cell neoplasm gel?
IgG spike
What are two important clinical predictors of plasma cell neoplasms?
B2-microglobulin (bad) and del 17p (p53) - bad
What is the common immunophenotype of plasma cell neoplasms?
CD38+++
CD138+++
light chain restricted
Describe follicular lymphoma pathogenesis
Failure of germinal center B-cells to undergo apoptosis because they overexpress Bcl-2 due to translocation under IgH
What are some morphological findings of follicular lymphoma?
No polarity
No tingible body macrophages (no food!)
Reduced mitotic figures (bad, normally high)
Major immunomarker of follicular lymphoma?
BCL-2+
Genetic translocation in most follicular lymphomas
t(14;18) in 85%
Describe the prognostication of follicular lymphoma
Depends highly on grade; may progress to diffuse large B cell lymphoma
How is follicular lymphoma graded?
Amount of large cells (centroblasts)
Which is bigger, centroblasts or centrocytes?
Centroblasts
Diffuse large B cell lymphoma immunophenotype
CD19
CD20
CD10
Name two common translocations in diffuse large b cell lymphoma
t(v:3) Bcl-6
t(14;18) Bcl2-IgH
Most common presentation of Hodgkin’s
Males 30-50 with adenopathy
Morphology of Classical Hodgkin’s
Highly variable; look for Reed-Sternberg “owl eyes” cells
Diverse background of other cells
+/- Nodular fibrous bands
Morphology of Nodular lymphocyte predominant Hodgkin’s
Smaller R-S cells with less prominent nucleoli (“Popcorn cells”)
What is a Reed-Sternberg cell?
Rearranged Ig genes
Constitutive NFkB expression from mut or EBV
Or other apoptosis mutations
NO Immunoglobulin expression!
Immunophenotype of Classical Hodgkin’s
CD30+ (very important)
CD15+
pax5+ (b cell TF)
Key clinical predictors of Hodgkin’s
Stage and histological type
What is one way to differentiate between types of Hodgkin’s using cell surface markers?
Use +/- immunoglobulins on R-S cells:
+ is Nodular
- is classical
