Topic 24: intro to lymphoma. DO FIRST before lymphoma cards Flashcards
what is leukemia, lymphoma and plasma cell dyscrasia? generally
Leukemia: tumors that primarily involve the bone marrow and the peripheral blood.
Lymphoma: tumors that produce masses in involved lymph nodes or other tissues.
Plasma cell dyscrasia: tumors of the plasma cells which are usually present as discrete masses in the bones and causes systemic symptoms related to the production of a complete or partial monoclonal immunoglobulins.
In some cases, lymphomas or plasma cell tumors spill over to the peripheral blood, creating a leukemia-like picture. Conversely, leukemias can infiltrate lymph node, creating a histological picture of lymphoma. It’s important to know what kind of tumor cell it is, not location!
What must be done to classify the neoplasia?
-immunohistochemistry and flow cytometry to see markers and lineage specific antigens
this is important because lymphoid neoplasms are all monoclonal (originate from single mutated cell)
There are 4 ways to technically characterize leukemia of lymphoid origin (a lot of overlap with lymphomas)
- Hodkins vs Non-hodkins lymphoma
- Kiel classification: Low grade vs. High grade lymphoma
- characterization based on stage that differentiation block occurs
- WHO lymphoid leukemia classification
what is the characterization based on maturation stage?
having a block in a certain stage and accumulate in the previous stage
- Block in the bone marrow=pre germinal center tumor: acute lymphoblastic leukemia (ALL)
- Block in the germinal center: follicular lymphoma (t(14:18), Burkitt lymphoma t(8:14)
- Post Germinal center tumors: multiple myeloma
the majority of lymphoma are blocked at what stage?
The majority of the lymphomas are originated in the germinal center stage (or even post GC stage)
This is due to the somatic hypermutation and the immunoglobulin class switching, which generate genetic instability and place the B cells at relatively high risk for mutations that can lead to transformation. The genetic alterations are not enough in order to develop lymphoma, but other alterations should be present.
what is the treatment for B cell lymphoma?
MabtherA
merged Fab (mouse) and Fc (human) that is anti-cd20 to specifically target the B cell
According the the WHO lymphoma classification, how is it roughly divided?
B or T/Nk cell vs progenitor or mature stage
In the HL vs. NHL classification, what is the defining characteristic of HL?
- Reed-Sternberg cell - a cell with very prominent nucleoli
- HL is B cell originating lymphoma
- HL occurs often in a single group of lymph nodes
- NHL is a B or T cell origin
- NHL involves multiple peripheral nodes, messenteric nodes and waldeyer’s ring and has extranodal involvement (peripheral blood, BM)
What is the Kiel classification?
B or T cell and low-grade or high-grade
what is low grade lymphoma?
Low grade lymphoma: “citic”- composed of small cell. the mitotic figures and the proliferation is extremely low.
Survival is longer, good prognosis.
The problem is t(14,18) → upregulation of bcl2 → no apoptosis → cells accumulate.
With chemotherapy the prognosis is a little bit better, but not treatable (just prolongs a little the life)
what is high grade lymphoma?
High grade: “blastic” - large atypical cells and many cells with mitotic figures.
Proliferation is high. Bad prognosis: rapid death.
T(8,14) → upregulation of cMyc → pushing the cell for proliferation.
With chemotherapy: 50% chance to be cured!!
