Flashcards in Hematopathology 1 Deck (44)
How are hematopoietic malignancies classified?
acute (presence of blasts - very immature cells)
chronic (presence of differentiated, mature cells)
What 2 cell types are involved in hematopoietic malignancies?
What characterizes leukemias?
malignant neoplasms of hematopoietic cells that replace bone marrow
True or false: leukemic cells usually spill over into peripheral blood
What differentiates a leukemia from lymphoma?
leukemia = present with widespread involvement of bone marrow and blood
lymphoma = describes proliferation arising as discrete tissue masses
What 3 blood metrics are common in ALL and AML?
What are some clinical features of acute leukemias?
- abrupt stormy onset
- depression of normal marrow function (fatigue (anemia) fever (neutropenia) bleeding (thrombocytopenia))
80% of acute leukemias of in children are _____
(acute lymphoblastic leukemia)
When is the peak incidence for ALL in kids?
4 years (but most under 15 years)
What kind of cells are neoplastic in ALL?
lymphoblasts (precursor B or T lymphocytes)
What are the majority of ALL neoplastic cells?
pre-B cell neoplasms
What is the main population at risk for T-ALL?
What are microscopic tools to diagnose ALL?
lymphoblasts show scant basophilic cytoplasm and fine nuclear chromatin
What are the markers used to diagnose ALL?
Terminal deoxynucleotidyl transferase (TdT)
CD19, 20, 21 (B cells)
CD1, 2, 3, 4, 5, 7, 8 (T cells)
TdT is diagnostic for which blood cancer?
acute lymphoblastic leukemia
True or false: 90% of ALL patients have numerical or structural changes in chromosome of leukemic cells correlating with immunophenotype and prognosis
What are the 4 chromosomal changes found in ALL?
1) hyperdiploidy (>50 chromosomes)
2) TEL1-AML1 (t(12;21))
3) BCR-ABL (t(9;22))
4) AF4-MLL (t(4;11))
What are 3 favorable prognostic indicators in ALL?
1) age 2-10
3) t(12;21) TEL1-AML1
What are 3 UNfavorable prognostic indicators of ALL?
1) age under 2
2) adolescent or adult
3) presence of t(9,22) PHILADELPHIA chromosome
What is the philadelphia chromosome?
first genetic link to cancer
What is acute myeloid leukemia?
a disease of adults peaking after 60 years (only 20% of childhood leukemias)
What are the neoplastic cells in AML?
heterogenous disease (reflects the complexities of myeloid cell differentiation)
What AML associated genetic abnormality has the worst prognosis?
What are 4 WHO classifications of AML?
1) AML with recurrent genetic abnormalities
2) AML arising from myelodysplastic syndrome (MDS)
3) therapy related
4) not otherwise specified)
GENERALLY ARISE FROM MDS
Define myelodysplastic syndromes (preleukemia)
clonal stem cell disorders showing defective and ineffective hematopoiesis with increased risk for transformation to AML
What are the two types of MDS?
2) therapy related (following chemo)
What are signs of myelodysplastic syndrome?
1) hypercellular marrow with peripheral cytopenia (poor hematopoiesis)
2) clonal cytogenetic abnormalities
3) MDS arise on a background of stem cell damage
4) morphologic abnormalities seen in all lineages (mostly nuclear)
How can the bone marrow be hypercellular but still have peripheral cytopenia in AML?
bone marrow cells apoptose
What are some of the morphologic findings in myelodysplastic syndrome?
1) highly abnormal RBCs
2) megakaryocytes with multiple, separated nuclei
What kinds of MDS subtypes are associated with a poorer prognosis?
those with higher blasts in blood or marrow
(leads to worse cytopenia)
Which disease, ALL or AML, has more severe signs/symptoms related to infiltration of tissues?
ALL (although AML does have some mild lymphadenopathy and organomegaly)
Which disease, ALL or AML leads to CNS problems?
In which type of acute leukemia is DIC found?
acute promyelocytic leukemia 1(15;17)
What is the most severe acute leukemia that if you suspect it even a little bit you should begin treatment?
APL (need to initiate therapy in order to avoid bleeding in the brain)
What is the main morphological hallmark of APL?
auer rods (HUGEly diagnostic)
little rods in the cytoplasm
What is the fusion gene for APL?
abnormal retinoic acid receptor that blocks myeloid cell differentiation
How can you treat the differentiation block in APL?
What cancer can you treat by giving trans retinoic acid?
What are 4 diagnostic signs of AML?
- myeloblasts >20%
- myeloperoxidase or alpha napthyl butyrate esterase stains
- CD13, 33, 34, 117
- AUER RODS
What is the strongest support of an AML diagnosis?
What type of cancer has multiple auer rods?
What is the prognosis for AML
GOOD for t(15;17) t(8;21) of inversions of chromosome 16
POOR for chromosome 11q23 (MLL)
What two genetic mutations are implicated in AML and what are the prognoses for them?