Week 2 Flashcards
Pancytopenia
loss of all cell types, anemia, thrombocytopenia, leukopenia
What is a “leuko-erythroblastic picture”?
bone marrow cells seen on peripheral blood smear
What findings suggest bone marrow pathology?
nucleated red cells, basophilic stippling, Howell-Jolly bodies, giant platelets, myelocyte, blasts
What 3 things will be obtained in a bone marrow biopsy and why?
- Aspirate (.5 cc) for morphologic studies
- Additional aspirate for special studies (5-20cc)
- Core biopsy for histological studies
What sample from the bone marrow biopsy will be hemodilute?
aspirate for special studies
Blasts should make up less than ____% of cell in bone marrow.
5
Myeloid cells should outnumber erythroid cells by what ratio?
2:1 to 5:1
How is the cellularity of bone marrow biopsies estimated?
100%-age; the rest is fat
___ is the best way to gauge a pt’s iron stores.
looking directly at bone marrow
B cell antigens
CD45, CD79a, CD 20, CD 10, kappa and lambda light chain
T cell antigens
CD45, CD4, 7, 8
The most reliable means of counting particular cell types is ____.
flow cytommetry
The aspirate used in flow cytometry is usually ____. What is done about this?
hemodilute; red lysis procedure will lyse erythroid precursors
___ scatter in flow cytometry is proportional to cell size.
foward
___ scatter in flow cytometry is indicative of granules or segmented nuclei.
side
What are the 2 methods of immunophenotyping?
flow cytometry and immunohistochemistry
CD34 is a marker of what?
hematopoietic stem cells
CD33 is a marker of what?
granulocytes
Routine cytogenetic studies identify and number the chromosomes present in _____ cells.
dividing (metaphase)
Routine cytogenetics can identify a philedelphia chromosome. This is indicative of what disease?
Chromosome 22: Chronic myelogenous leukemia
What are the methods of identifying abnormal genotypes?
routine cytogenitics, FISH, PCR, complete genome sequencing
Describe the philedelphia chromosome and who identified it
translocation between 9 and 22. Janet Rowley
FISH visualizes cells in what phase?
interphase
What mutations are needed in AML?
Class 1: proliferation advantage
Class 2: impaired differentiation/apoptosis
When using PCR to assess an AML pt with normal cytogenetic findings, what 2 samples are used?
leukemia cells, skin biopsy
Why is complete genome sequencing unlikely to be a routine clinical procedure?
most mutations are likely irrelevant, epigenetic changes could play a role
What type of malignancies arise from mutations in HSC?
- acute leukemia
- myeloproliferative disorder
- Myelodysplastic syndrome (MDS)
What HSC malignancy has rapidly proliferative clones, lots of blasts in BM and often blood stream?
acute leukemia
What HSC malignancy has chronically proliferating clones which differentiate to circulating cells (normal but high numbers)
myeloproliferative disorder
What HSC malignancy has poorly functioning clones (normal number)?
myelodysplastic disorder
What is acute myeloid leukemia?
rapidly proliferating clones; blasts in marrow and often blood stream in the myeloid, erythroid, and meg lineages
What is acute lymphoid leukemia?
malignancy with rapidly proliferating clones; blasts in bone marrow and often blood stream of lymphocyte lineage
What type of acute leukemia appears to be derived from stem cells which have not committed to a lineage?
acute undifferentiated leukemia
What are the 3 clinical presentations of acute leukemias?
- many blasts in blood and marrow
- few blasts in blood, many in marrow
- blasts outside marrow such as myeloid sarcoma or lymphoblastic lymphoma
A marrow blast number of ____ usually implies acute leukemia.
greater than 20%
What are the advantages of genotype diagnostic criteria?
increased prognostic value, predicts response to therapy, identifies moelcular targets for therapy development
What 4 things may be used to diagnose?
blast count, blast mophoplogy, imuunophenotype, genotype
A mutation in Jak2 is what type of mutation?
Class 1
How are the Class 1 and 2 mutations needed for AML identified?
cytogenetic analysis, genomic sequencing
Describe the genetics of AML with t(8:21); Runx1-Runx1T1
fusion protein of 2 transcription factor, 5% of AML; dominant negative repressor of myeloid maturation (class 2 mutant). Requires Class 1 mutation concurrently.
how is t(8:21) Runx1-runx1t1 identified?
cytogenetics
Clinical presentation of pt with AML with t(8:21); Runx1-Runx1T1
younger pt/kids
Morphology of AML with t(8:21); Runx1-Runx1T1
some maturation to myelocytes, occasional crystallization of granule contents (Auer rods)
Immunophenotype of AML with t(8:21); Runx1-Runx1T1
CD34+, HLA-DR+, CD13+, CD33 weak
What is the prognosis of AML with t(8:21); Runx1-Runx1T1
good response to chemo
Describe the genetics of AML with t (15:17) PML-RARA
fusion of PML (transcription factor) with RARA (transcription factor) occurs in 5-8% of AML cases. This results in Class 2 dominant negative blockade of differentiation.
Clinical presentation of AML with t (15:17) PML-RARA
DIC, severe thrombocytopenia
Morphology of AML with t (15:17) PML-RARA
big blasts, cleaved “bat wing” nuclei, many granules, auer rods in stacks
immunophenotype of AML with t (15:17) PML-RARA
weak/absent CD34, HLA-DR+, CD13+, CD33+
Prognosis and Rx of AML with t (15:17) PML-RARA
Good if diagnosis is made: ATRA is an RA analogue that blocks PML-RARA. It induces differentiation of blasts to granulocytes –> clinical remission
HOw is AML with t (15:17) PML-RARA identified?
cytogenetics
Auer rods are diagnostic of ____.
AML
Describe the genetics of AML with inv(16); CBFB-MYH11
Class 2 dominant negative repressor of myeloid maturaion
How is the mutation of AML with inv(16); CBFB-MYH11 identified?
cytogenetics
Clinical presentation of AML with inv(16); CBFB-MYH11
younger pt/kids
Morphology of AML with inv(16); CBFB-MYH11
mixed granulocyte-monocyte features (myelomonocytic). Increased eosinophilia in blood and marrow
Immunophenotype of AML with inv(16); CBFB-MYH11
CD34+, CD117+, CD13+, CD33+, CD14+, CD11b+
What markers are found on monocytes?
CD14+ and CD11b+