Myeloproliferative Neoplasms (MPNs) & Myelodysplastic Syndromes (MDS) Flashcards
myeloproliferative neoplasms definition:
heterogeneous group of CLONAL myeloid neoplasms characterized by sustained PROLIFERATIONG of one or more cell types in the peripheral blood, with minimal dysplasia (EFFECTIVE HEMATOPOIESIS) and variable progression to acute leukemia
myeloproliferative neoplasms features:
- chronic bone marrow disorders
- excess growth in myeloid cell line (RBC, WBC, PLTS)
- similar signs and symptoms with some overlap
common features of all myeloproliferative neoplasms:
1) insidious nset
2) initial chronic and relatively indolent phase
3) progressive erythrocytosis/leukocytosis/thrombocytosis
4) BASOPHILIA, SPLENOMEGALY
5) variable bone marrow fibrosis and failure
6) transformation to acute leukemia (blastic phase)
7) underlying molecular events knows -BCR/ABL1, JAK2
Chronic myelogenous leukemia (CML) -
1) what gene associated?
t(9,22) - philadelphia (Ph) chromosome - BCR/ABL1 fusion gene
most common MPN?
chronic myelogenous leukemia
1st leukemia described?
Chronic myelogenous leukemia
1st leukemia associated with chromosomal abnormality?
Chronic myelogenous leukemia
Disease for which “leukemia” (white blood) is coined?
Chronic myelogenous leukemia
Chronic myelogenous leukemia
-mediam age of diagnosis?
-median age 46-53 years at Dx but can occur at any age*
Chronic myelogenous leukemia
-clinical features:
- FREQUENTLY ASYMPTOMATIC*
- weakness, fatigue, lethargy, WL
- fever, NS, gout (hyperuricemia)
- bleeding, pallor, dyspnea
- splenomegaly
- tri-phasic disease: chronic-accelerated - blast
Chronic myelogenous leukemia - pathologic features of blood smear in chronic phase:
1) granulocytes?
2) neutrophils? other granulocytes?
3) blasts?
4) platelet/clotting related?
1) Severe left-shifted granulocytosis at all stage - 30K to 100K
2) neutrophilia with “myelocyte bulge” ; eosinophilia, monocytosis, basophilia; basophils <10%
3) blasts 1-2%
4) thrombocytosis common, thrombocytopenia rare
myelocyte bulge- think which sample and disease?
- Chronic myelogenous leukemia - CHRONIC PHASE = neutrophilia
- blood smear
Chronic myelogenous leukemia - pathologic features of bone marrow biopsy & aspirate in chronic phase:
1) cell number?
2) Myeloid:Erythroid (M:E) ration?
3) Blasts % and basophils %?
4) megakaryocytes appearance?
5) special cells? where are normally seen?
1) markedly hypercellular bc granulocyte & megakaryocyte proliferation
2) >10M:1E (normal is (2-3M):1E)
3) blasts
dwarf megakaryocytes - which sample and which disease?
- Chronic myelogenous leukemia - CHRONIC PHASE
- bone marrow aspirate and biopsy
How are pseudo-gaucher cells seen on bone marrow aspirate? what does this mean?
sea-blue histiocytes
-really high cell turnover
What are the ancillary studies involved in CML?
1) conventional cytogenetic analysis (karyotype) - cell in metaphase state: find 9,22 translocation
2) fluorescence in situ hybridization (FISH) - find 9,22 translocation - MORE SENSITIVE TEST!
3) qualitative/Quantitative polymerase chain reaction - find BCR/ABL1 mRNA
CML - Chronic myelogenous leukemia-
-Pathophysiology:
- 9,22 translocation = BCR/ABL1 protein tyrosine kinase is
- constantly active bc it can transfer a phosphate activating group to itself and generates signals that mimic the effect of growth-factor activation
- cells are less dependent on normal growth factor receptor signals for growth
- proliferative and differentiate unchecked
- anti-apoptotic effects
Chronic myelogenous leukemia - CML:
- three different gene regions of BRC:
- most common?
- Major p210 breakpoint: vast majority of CML* w/ conventional pathological characteristics
- Minor p190 breakpoint: seen in Ph chromosome ALL and CML with monocytosis
- p230 Breakpoint: CML with thrombocytosis
***Which BCR gene region is most common in CML?
p210 breakpoint***
p210 breapoint disease associations?
conventional CML with usual pathologic characteristcs
p190 breakpoint diease associations?
Ph chromosome ALL and CML with monocytosis
p230 breakpoint disease associations?
CML with thrombocytosis
CML - accelerated phase disease basically means? Other features?
- if left untreated the blasts and basophils will continue to increase
- -Peripheral blood or bone marrow blasts: inc to 10-19% (must be less that 20%)
- -peripheral blood basophils: inc to >20%
- persistent thrombocytopenia or thrombocytosis (unrelated or unresponsive to therapy)
- worsening leukocytosis, splenomegaly
- clonal evolution by cytogenetic analysis
Acute leukemia definition? related to CML accelerated phase?
-acute leukemia has >20% blasts while CML-accelerated has 10-19% increase
CML-blast phase:
- characteristics?
- myeloid vs lymphoid blasts pregression? significance?
-Peripheral blood or bone marrow blasts >20%
- myeloid-blast phase- 50-60%
- lymphoid blast phase- 15-30%
- Myeloid blast phase more often than lymphoid (this cancer can jump lineages)
How to distinguish lymphoid and myeloid lineage CMLs? which phase?
- immunophenotyping via flow cytometry
- blast phase CML
CML Treatment:
- tyrosine kinase inhibitors (Imatanib/Gleevac)
- stem cell transplantation for younger patients
CML prognosis:
- if chronic phase=6 years chronic phase
- if blast phase=terminal
- imatanib (Gleevac): prolonged survival
- goal to eradicate clone in Chronic Phase (CP), prevent AP (acute/accelerated phase)/BP (blast phase)
imatanib is treatment for?
CML
CML - differential diagnosis for chronic phase and for accelerated/blast phase?
1) Chronic Phase:
a) leukemoid reaction
b) other MPNs, aCML, CMML
2) Accelerated/Blast:
a) MPN/MDS
b) AML
c) ALL
What is a leukemoid reaction?
reactive benign neutrophilia due to infection or inflammatory state
What do you see in a benign leukemoid reaction vs a neoplastic CML?
Leukemoid /// CML
- Nml response to infection /// Clonal MPN
- WBC30-60K
- Segs and bands /// myelocyte bulge
- no basophilia or splenomegaly /// Yes to basophilia and splenomegaly
- explained clinically /// unexplained
- LAP (leukocyte alkaline phos) score elevated /// LAP score decreased
- normal megakaryocytes /// dward megak
Polycythemia vera-PV:
Definition:
Characteristics:
1) MPN with increase RBC production
2) characteristics:
* *a) INCREASED RBC MASS ( RBC, HGB, HCT)
b) may affect all cell lines
* *c) MEDIAN AGE 60 YEARS AT DIAGNOSIS
d) 5% younger than 40 yrs
e) a little bit more males than females affected
f) rarely develop into AML