Lymphocytic Neoplasia Flashcards
What three cells make up lymphocytes?
B cells ,T cells NK cells
What is the difference between leukemia and lymphoma?
Leukemia is when the lymphocyte neoplasm is primarily in the blood or bone marrow
Lymphoma is when the primary lymphocyte neoplasm is in the lymph node or solid tissue like the spleen
How are leukemias and lymphomas classified?
Genetically, phenotypically and morphologically
What is an immunophenotype?
What two things can it help you infer?
an antigenic “fingerprint” of cells determined by the types of molecules they express.
It can infer:
1. cell lineage
2. documentation of abherrant expression
What are the normal B cell markers?
CD19, 20, 22
CD79a
Pax 5
k and l Ig light chains
What are the typical T cell markers?
CD1a, 2, 3, 4, 5, 7, 8
What are the typical NK cell markers?
CD 2, 7, 8 (same as T)
CD 16, 56
What is CD45?
Leukocyte common antigen. It is seen on all normal leukocyte populations (except plasma cells)
What are the markers from Hodgkin’s lymphoma?
What can the markers allow you to do?
CD 45 CD 30 CD 15 CD 20 CD 3 The markers can help you differentiate between classic hodgkins and nodular lymphocyte predominant Hodgkins
What are CD34 and TdT markers for?
What other marker has the same principle role, but is more specific?
They are a sign of immaturity in lymphoid populations so can tell you if the leukemia/lymphoma is blastic.
CD1a is also an immaturity marker but only for T cells
What are the CD10 and CD5 marker useful for?
They help subcategorize B-lineage lymphomas and leukemias.
Certain B-cell lymphomas have neither of these markers.
Other B-cell lymphomas have ONE of these markers.
NO B-cell lymphoma have both.
What is Ki67 a marker for?
Cell proliferation which can help us determine the number/percentage of neoplastic cells that are actively proliferating.
What are the techniques used for cytogenetic investigation used to categorize leukemia/lymphoma and aid in prognosis and therapeutic planning?
FISH and karyotyping (because a lot of the lymphocytic neoplasms are translocations)
Tumors compose of immature lymphocytes are designated with what 4 titles?
Tumors of mature lymphocytes are designated by what 2 titles?
Immature:
- blastic
- acute
- precursor
- central
Mature:
- chronic
- peripheral
What “blast” is not really an immature lymphocyte?
Immunoblast- is a transformed, reactive, mature lymphocyte that has a few features that appear immature (dispersed chromatin, large nucleoli)
What is lymphocytosis? What are 4 potential causes?
It is too many lymphocytes in the periphery.
- Chronic immunologic stimulation (TB)
- Viral infection
- Bordetella pertussis
- Stress (car accident, cerebral vascular accident)
Neoplasms of immature lymphoid cells arise from:
- defects in stem cells that lead to clonal expansion of leukemic blasts
- secondary suppression of normal hematopoiesis`
What are the two major types of acute lymphoblastic leukemia/lymphoblastic lymphoma (ALL/LBL) ?
Which are 85% of the cases in the US?
- B-ALL/LBL- immature B cells “hematogones”
- T-ALL/LBL- immature T cells “thymocytes”
B-ALL/LBL accounts for 85% of cases in US
What is a hematogone? What cancer is it associated with?
What are the markers?
It is an immature B cell in B-ALL/LBL
CD19, 22, CD79a (sometimes CD20)
CD10
CD34 and Tdt
What is a thymocyte? What cancer is it associated with?
What are the markers?
It is an immature T-cell associated with T-ALL/LBL.
CD1a, 2, 3, 4, 5, 7, 8
CD34, TdT
Benign counterparts of hematogones and thymocytes express the same markers. How do you differentiate benign from neoplastic?
The intensity and pattern of the expression
What is the age distribution for ALL/LBL?
Bimodal with a peak in early childhood and the elderly (over 65)
What are common symptoms of ALL/LBL?
- bone/joint pain (due to overproduction of precursor WBC in the marrow)
- Lymphadenopathy
- skin lesion
- organomegaly
What mass is associated with T-ALL/LBL?
anterior mediastinal mass with or without vena caval syndrome
Is ALL/LBL aggressive or indolent?
Is it curable or incurable?
Both B an T forms are highly aggressive and require intense chemo.
Cure rate is high in children with continued therapy (3 years after undetectable)
Cure rate is bad in elderly (less than 10% make it 3 years)
Speaking generally, what is the difference in cure rate between indolent and aggressive cancers?
Indolent are not that bad and people can live with them for a long time, but there is no cure.
Aggressive need to be caught early because they can be devastating, but if caught early, they can be cured.
What are the two broad categories of mature lymphoma?
- Non-Hodgkin’s lymphoma
2. Hodgkin’s lymphoma
Non-Hodgkins lymphomas (NHL) are roughly _____% B cell lineage and ___% T cell lineage.
80% B cell
20% T cell
NK are categorized as T cell lymphomas because of the similar clinical behavior
Where do the majority of NHLs manifest predominantly?
Where do the remaining cases occur?
60-70% are in the lymph nodes.
The rest are in extra-nodal locations
What are the 3 ways a NHL can arise?
- polyclonal lymphoid proliferation with a second mutation allowing for a monoclonal outgrowth (MALT with chronic gastritis)
- Translocation of an oncogene into an antigen receptor locus (Ig or TCR) to overexpress the oncogene
- genetic rearrangement to make a novel hybrid protein with uncontrolled cell growth
What are the characteristics of an indolent (low grade) lymphoma?
- cell size
- rate of proliferation
- location
- small lymphoid cells
- low rate of proliferation
- disseminated at presentation
Basically, because the cells are so small and grow so slowly, it was disseminated before the person even noticed
What are the characteristics of aggressive lymphomas?
- cell size
- rate of proliferation
- location
- larger cells
- high rate of proliferation (high expression of Ki67)
- localized at presentation