Lymphomas Flashcards
What are the B cell Non-Hodgkin Lymphomas?
Follicular lymphoma
Mantle cell lymphoma
Burkitt lymphoma
Diffuse large B cell lymphoma
How would you diagnose a lymphoma?
You need an excisional tissue or lymph node biopsy
List some common B Cell markers
CD19
CD20
List some common T cell markers
CD3
CD2, 4, 5, 7, 8
Follicular Lymphoma
Symptoms
Painless lymphadenopathy
They may be totally asymptomatic
Follicular Lymphoma
What is the morphology of the cells?
Centrocytes
Small cells with cleaved or irregular nuclei
Centroblasts
Large cells with open nuclear chromatin and many nucleoli
Follicular Lymphoma
What chromosomal translocation is common? Why does this cause lymphoma?
t(14;18)
BCL2 / IGH fusion
BCL2 (anti-apoptotic) gets overexpressed along with the IGH gene
Follicular Lymphoma
What is seen on lymph node histology?
Tons of follicles all bunched up, not just underneath the capsule
Follicular Lymphoma
What is seen on gross imaging of the spleen?
Lots of white dots all over, which are many follicles proliferating
Follicular Lymphoma
How can you look at this disease with immunohistochemical stain?
Stain for BCL2 expression in the follicles
Mantle Cell Lymphoma
What is the appearance of the cells present?
Small cells with irregular nuclei
Mantle Cell Lymphoma
What chromosomal translocation is common? Why does this cause lymphoma?
t(11;14)
Fusion of the Cyclin D1 and IGH genes
Leads to overexpression of Cyclin D1, which causes increased cell proliferation
Burkitt Lymphoma
Who most commonly presents with this disease?
Kids and young adults
Burkitt Lymphoma
Symptoms
Tumors at extranodal sites (mandible tumors, abdominal tumors)
Burkitt Lymphoma
What is the appearance on histology?
Starry Sky Pattern
See lots of dark cells with some clear areas (benign macrophages clearing up apoptotic debris)
Burkitt Lymphoma
What chromosomal translocation is common? Why does this cause lymphoma?
t(8;14)
Fusion of the MYC and IGH genes
Causes overexpression of MYC
What are some other causes of Burkitt Lymphoma (not due to chromosome translocation)?
B cell neoplasm
EBV infection
HIV infection
What is the most common form of lymphoma in adults?
Diffuse large B cell lymphoma
Diffuse Large B Cell Lymphoma
What are the two distinct subtypes? Which has better survival?
Germinal center B Cell (GBC)
Activated B Cell (ABC)
GBC has better survival
Diffuse Large B Cell Lymphoma
What is the clinical presentation?
Rapidly enlarging symptomatic mass at single or extranodal site
Diffuse Large B Cell Lymphoma
What genetic abnormalities may be present?
30% have t(14;18) - BCL2 overexpression (anti-apoptosis)
30% have BCL6 rearrangement
Some have MYC rearranged to increase cell proliferation
Diffuse Large B Cell Lymphoma
What is the appearance on histology?
Large cells (4x normal size)
Vesicular chromatin ("bubbly" appearance of chromatin)Peripheral T Cell Lymphoma NOS
Clinical Presentation
Lymphadenopathy Eosinophilia Pruritis (itchy skin) Fever Weight loss
Peripheral T Cell Lymphoma NOS
How would you make the diagnosis of this disease?
Demonstrate it is a T cell (CD3+) with immunophenotypic and genotypic analysis
Normal T cells would also express CD5, but the neoplastic T cells in PTCL NOS do not express CD5
Hodgkin Lymphoma
Who tends to get this?
Young people (20s) and very elderly
Hodgkin Lymphoma
Where does it arise?
Generally arises in one lymph node and spreads contiguously to the nearby lymphoid tissues
Hodgkin Lymphoma
What are the characteristic cells?
Reed-Sternberg cells (Owl eyes)
List the 4 classic Hodgkin Lymphomas
Lymphocyte rich
Mixed cellularity
Lymphocyte depleted
Nodular sclerosis
What is the non-classic Hodgkin Lymphoma?
Nodular lymphocyte predominant
Hodgkin Lymphoma
What are the neoplastic cells? What activates the reactive cells?
B cells are neoplastic.
Reactive cells most likely due to cytokines made by RS cells
Hodgkin Lymphoma
What two antigens are expressed on the cell surface of classic Hodgkin Lymphoma?
CD15 and CD30
Hodgkin Lymphoma
What two antigens are expressed on the cell surface of NON-classic Hodgkin Lymphoma?
CD20 and CD45
Hodgkin Lymphoma
How would you make a diagnosis of nodular sclerosis?
If there is fibrosis present, you know it is nodular sclerosis
Hodgkin Lymphoma
How would you make a diagnosis of Lymphocyte Rich?
Lots of reactive small lymphocytes
Not too many RS cells
Hodgkin Lymphoma
How would you make a diagnosis of Mixed Cellularity?
Lots of RS cells with eosinophils, plasma cells, T lymphocytes, histiocytes
Hodgkin Lymphoma
How would you make a diagnosis of Lymphocyte Depleted?
Lots of RS cells with few reactive lymphocytes
What is the general appearance of Reed Sternberg cells?
“Owl eyes”
Binucleate
Big eosinophilic cells
May be mononuclear
Lacunar variant - more white space in cell(?)
What is the classic cell seen in Nodular lymphocyte Predominant Hodgkin Lymphoma?
Popcorn cells
Express CD20 and CD45
