CLL and Non-Hodgkin Lymphoma Flashcards
What are the layers of a follicle beginning in the middle and moving outwards?
Germinal center, mantle zone, marginal zone.
Makes sense right?
Germ=seed
mantle=crust
margin=past the crust.
What types of cells are found in the Medullary cord of the Medulla of a lymph node?
Plasma cells, MacrophagesLymphocytes
These are the darker areas of the medulla
What types of cells are found in the medullary sinus of the medulla of a lymph node?
Histiocytes.
These are the lighter areas of the medulla.
The dark zones of a germinal center contain mostly _______ while the light zones of a germinal center contain ____, ______, ______, and ______
centroblasts (immature B cells) mixed centrocytes (Mature B cells), T cells, dendritic cells, and histiocytes
The medulla is in what part of the lymph node?
paracortex
CD20 is a marker that highlights _____ and _____ B cells (location).
mantle zone
germinal center
What are the important B cell markers for immature B cells (germinal center/ mantle zone)?
CD19, CD20, CD22 (CD20 is the most important)
Remember B-ALL and T-ALL? Same story.
What are important cell markers that are positive in paracortical T cells?
CD3, CD4, CD5, CD8 (CD3 is the most important).
Remember B-ALL and T-ALL? Same story.
What hematologic malignancies arise from problems in Immature B-cells?
Acute lymphoblastic leukemia or lymphoma (B-ALL/LBL)
What hematologic malignancies arise from problems in a mantle cell?
mantle cell lymphoma
What hematologic malignancies arise from problems in Germinal center B-cells?
Follicular lymphoma
Burkitts lymphoma
Hodgkin lymphoma
What hematologic malignancies arise from problems in pre- or post-germ center B cells?
Chronic lymphocytic leukemia/Small Lymphocytic Lymphoma (CLL/SLL)
What hematologic malignancies arise from problems in plasma cells?
plasma cell myeloma
A soccer ball appearance is a morphologic feature of cells associated with what hematologic malignancy?
CLL/SLL
CD10 and BCL6 are both expressed in normal ______.
Normal germinal B cells
What are pseudofollicles?
They are proliferation centers–pale areas containing transformed larger cells. It is seen in SLL where the lymph node is so packed full of cells that normal lymph node histology is indeterminable.
In CLL/SLL which markers would we expect to be positive and which would we expect to be negative?
positive: CD5, CD23, CD19 (CD5 is a T cell marker so this is abnormal, and CD23 is just a weird one, CD19 is normal B cell marker)negative: CD10 (this is because CD10 is a germinal center B-cell marker. CLL/SLL is with pre- and post-germinal center cells)
T or F: under regular conditions the follicles should be variable in size?
True.They should also be far apart (not touching), and only in the cortex. FL reverses all these observations.
What happens to the location of follicles in follicular lymphoma?
They spread all over the lymph node (they are not just in the cortex as they should be).Also they to touch each other. In normal lymph node they should be far apart
In FL follicles are positive for _____. Normally they would be negative.
BCL2 gene
What does BCL2 do?
It turns off apoptosis. Want this to be turned off in the follicles of normal cells because want to allow for selection of lymphocytes. In Follicular lymphoma this is gene is on (due to the 14-18 translocation, this gene gets placed under the influence of a new promoter)
What are some of the important morphologic features of FL? Can you see tingible-body macrophages?
cannot identify mantle-zone or dark and light zone within germinal center.Do not see tingible body macrophages
What sort of cytogenetic finding is characteristic of FL?
t(14;18)
In FL B-cells are positive for which markers?
CD19, CD20 (B cell markers)CD10, BCL6 (germinal center B-cell markers)They are also BCL2 positive (the apoptosis gene)They are negative for CD5 and CD23 (this is how you can know that it isn’t CLL/SLL)
How do you tell the difference between reactive follicular hyperplasia (normal immune response) and Follicular lymphoma?
FL has strange morphologic features of the follicles that does not exist in hyperplasia:-tightly packed (sometimes touching)-monomorphic follicles (no variation in morphology- i.e. lost light zone, dark zone)-absent or obscured mantle zones-no tingible body macrophagesalso, reactive follicles would not be positive for the BCL2 gene which is turned on in FL.
over expression of cyclin D is a component of which hematologic malignancy?
Mantle Cell Lymphoma (MCL)
How does MCL Mantle Cell Lymphoma compare with B cell lymphomas in aggressiveness?
B-cell lymphomas are indolent
Whereas MCL is fairly aggressive.
MCL patients often present with Stage ___ or ___ lymphadenopathy and _____ involvement.
III, IVmarrow
What are some important morphologic features of Mantle Cell lymphoma?
tumor cells are small to medium size, slightly larger than normal lymphocytes. irregular nuclear contour. Especially–> nuclei have moderately dispersed chromatin and small nucleoli.
How can you tell MCL from other B cell lymphomas such as SLL using cell markers?
MCL is + for CD19, CD20, CD22 (B-cell markers)It is also + for CD5 (as in CLL/SLL). This is abnormal because it is a T cell marker.Unlike CLL/SLL MCL is - for CD23. It is also Negative for germ center IDs (CD10 and BCL6)MCL is positive for BCL1 gene (this is due to a gene rearrangement and leads to the cyclin D1 expression.positive- CD19, CD20, CD22, CD5, BCL1negative- CD23, CD10, BCL6
What is the role of cyclin D1?
It is important for G1/S transition and cell division. This is overexpressed in MCL.
What is the characteristic cytogenetic finding of MCL?
t(11;14) Involves the BCL1 gene which leads to cyclin D1 over expression.
What are the 3 types of Burkitts lymphoma and what do they all have in common?
EndemicSporadicImmunodeficiency-associatedAll these have EBV (ebstein-barr virus) association
What is characteristic of Endemic Burkitts lymphoma?
occurs in africa or in the malaria beltaffects jaw and abdomen most
What is characteristic of Sporadic Burkitts lymphoma?
affects the Ileocecal area
What is characteristic of Immunodeficiency-associated Burkitts lymphoma?
Primarily affects HIV patients (immunocompromised)
What is the characteristic cytogenetic finding of Burkitts lymphoma?
t(8;14) Changes the MYC gene (puts it next to the IGH promoter (that part is probably not that important))
Is Burkitts an aggressive or an indolent lymphoma?
aggressive
What are the cell markers for Burkitts Lymphoma?
It is a B cell lymphoma so it is + for CD19, CD20. It is also + for BCL6 and CD10 bc its in the germinal center. - for CD5 and CD23.Unique feature is that it is + for the MYC gene (turned on by the t(8;14) translocation).
What is the most common type of non-hodgkins lymphoma?
Diffuse Large B-Cell Lymphoma (BLBCL)
What is characteristic of the morphology of DLBCL?
Big Fatties. Large neoplastic B cells twice the size of a lymphocyte. nuclear size is greater than or equal to that of a histiocyte. Also, it is diffuse through the lymph node so the histological architecture of the lymph node is obliterated
How are the types of DLBCL subclassified?
by gene expression, location, and morphology
How do you tell the difference between a centroblast and an immunoblast?
Immunoblasts have a central notch nucleolus
