Lymphadenopathy Flashcards
When looking at histology at lymph node what is the biggest marker of neoplasia?
– Loss of Architecture, if you don’t see distinct follicles and other structures, then increased chances of it being neoplasia.
What are different clinical symptoms of reactive vs neoplastic lymphadenopathy?
Reactive: Fast growth, painful, systemic symptoms (fever, etc.) and usually mobile.
Neoplastic: Slow growing over time, nontender, no other associated symptoms, location of uncommon LAD
What scenerio might a patient have reactive follicular hyperplasia that is non-neoplastic?
Autoimmune Disorder
HIV
Toxoplasmosis
When would the paracortical region of the lymph node be hyperplastic, not associated with neoplasm?
EBV
CMV
Herpes
(Viruses, since.. T-cells)
A middle aged man with presents with progressive lymphadenopathy throughout his body over the past 6 months. Painless LAD with mild spenlomegaly.
Follicular Lymphoma
What would histology find in follicular lymphoma patient lymph node biopsy?
Follicular Hyperplasia – more numerous follicules and decreases paracortical space.
What would be the most common surface markers of Follicular lymphoma?
CD10 – usually found on B-cells
CD19/CD20 – mature B-cells
Negative CD5 (T-cells)
Negative CD23 (Naive Mantle Cells)
What is the therapy for progressive follicular lymphoma?
Anti-CD20 Therapy
– Rituximab – Causes Complement, CD8 killing, and Apoptosis of CD20 expressing cells.
If a patient with follicular lymphoma for many years suddenly notices a rapid increase in size of my lymph nodes, what is most likely responsible?
Follicular Lymphoma has a high rate of transformation into a more aggressive form.
- Diffuse Large B-cell Lymphoma
- Burkitt Lymphoma
What is the common mutation associated with follicular lymphoma?
– t(14,18) where IgH fuses with BCL-2 (anti-apoptosis), thus harder for the cell to induce apoptosis when damaged because there is alot being produced.
How can you differentiate between Burkitt and Large B-cell Lymphoma?
Both of them are positive for CD19/CD20, but Burkitt will additionally have CD10
What kind of lymphoma frequent arises from mucosal lymphoid tissue that slowly develops over time?
Lymphoma arising from Margin of Follicle
– Extranodal Marginal Zone Lymphoma –
(Usually in MALToma)
– t(11,18) MALT1-IAP2 fusion
What is the common mutation in mantle cell lymphoma?
t(11,14) – cyclinD-IgH fusion
Allow cell cycle progression
What translocation and gene action is common associated with “Starry Night” histology?
Translocations involving c-MYC and an immunoglobulin loci
– t(8,14) or t(2,8) or (8,22)
What is a common antigenic marker of Mantle cell lymphoma to differentiate it from others?
Mantle Cell = CD5+ CD23-
CLL/SLL = CD5+ and CD23+
What differentiates Follicular and Marginal Zone Lymphomas?
Follicular = CD10+ Marginal = CD10-
What lymphoma is most common associated with EBV outside of the US?
Burkitt Lymphoma - most commonly
Extranodal NK/T-cell lymphoma
What are the EBV proteins EBNA1/LMP2 responsible for?
Induces the B-cells to move into the germinal center and proliferate without antigen recognition.
What commonly keeps the EBV infected cells under control?
Cytotoxic T-cells, thus immune compromised individuals can have re-activation of EBV
Who commonly is infected with EBV and what can be a marker of acute EBV infection?
Most people are infected in developing countries, less people in developed countries.
- Downey Cells (expanded CD8+ T-cells)
- Heterophile antibody expression by B-cells
When can you detect anti-EBNA antibodies in the serum?
Usually takes the body significant amount of time to get the EBV infection under control and would not be observed until 3-5 months later.
How can EBV contribute to oncogenesis?
- Direct Transformation, EBV genes cause overexpression of certain genes/unstable genome. Can increase the risk of a translocation.
- Chronic Inflammation / Bystander Cells get induced
If you find an ALK gene rearrangement, what might be the lympoma you are dealing with?
Anaplastic Large Cell Lymphoma
– t(2,5) tyrosine kinase receptor activation
What patient populations are common found with EBV associated Burkitt Lymphoma?
- EBV-endemic areas
- - Immunosuppressed individuals
