20) MPN Flashcards
hypercellularity of the BM
dominance of one cell line in PB
MPN
3 most common cell lines involved in MPNs
- myeloid (CML)
- megakaryocytic (ET)
- erythroid (PV)
less common cell lines involved in MPNs
- fibroblasts
- eosinophils
- mast cells
- variable
MPN age group
40s-60s
in MPN, the BM eventually becomes ———
fibrotic
MPN can develop into…
acute leukemia
why might MPN result in splenomegaly?
EMH after BM fibrosis
only MPN with Philadelphia chromosome present
CML
3 stages of CML
- chronic: 2-10 years, responds well to therapy
- accelerated: 6-18 months
- blast crisis: 3-6 months, aggressive acute leukemia
median CML age of onset
70-90 years
loss of stamina
weakness
night sweats
weight loss
feeling of fullness
hepatosplenomegaly
CML
first signs of CML might be…
GI bleeding
retinal hemorrhage
plts don’t function well
clonal disorder of HSC; overproduction of defective granulocytes
CML
Philadelphia chromosome cell of origin
HSC
the Philadelphia chromosome is a juxtaposition of ——– proto-oncogene with a portion of ——- gene
ABL1
BCR
the novel BCR/ABL1 gene produces…
p210 fusion protein with abnormal tyrosine kinase activity
tyrosine kinase inhibitors
used to tx CML
platelets in CML
often > 1000 x 10^3
M:E 10-50:1
CML
leukemic hiatus is NOT seen in…
CML
CML erythropoiesis is normally…
normoblastic
may see pseudo-Gaucher
cells overloaded with cerebrosides
CML
indications of accelarated phase CML
- 10-19% blasts in PB
- basos in PB
- persistent thrombocytopenia or thrombocytosis
- additional chromosomal abnormalities
- 2+ mutations in BCR/ABL1 during TKI therapy (TKI resistance)
- splenomegaly unresponsive to therapy
blast crisis is ——- phase CML
terminal
clinical features similar to acute leukemia
CML can result in (AML/ALL) blast crisis
either one
mostly AML, but some ALL with Ph chromosome
rare MPN with sustained PB neutrophilia (>25 x 10^3) and mild left shift
chronic neutrophilic leukemia (CNL)
CNL is often associated with this cancer
MM
CNL median survival
2.5 years
parts of CNL diagnosis of exclusion
- other causes of neutrophilia ruled out
- no Ph chromosome
- no PDGFRA, PDGFRB, or FGFR1 mutations
- CSF3R mutation may be present
CSF3R mutation
CNL
bands + segs > 80% WBC
no dysgranulopoiesis
CNL
ET
essential thrombocythemia
MPN
pulmonary embolism
h/a
gangrene of toes and fingers
hemorrhagic episodes
palpable spleen
ET
ET median survival
19.8 years
ET can transform into…
PMF
acute leukemia
extreme and consistent thrombocytosis
giant bizarre platelets
ET
anemia in ET, if present, is ——-/——-
normo/normo
mutations in JAK2, MPL, or CALR
ET
mutation JAK2V617 rules out…
CML
PMF
primary myelofibrosis
——— is a very common cause of polycythemia
(not PV)
smoking
unregulated proliferation of erythroid elements in BM, and ↑ RBC
PV
mutations common in PV
JAK2 (V617F)
JAK2 exon 12
must differentiate PV from…
- relative polycythemia (↓ plasma volume)
- secondary polycythemia (↑ EPO)
inappropriate ↑ EPO causing polycythemia may be caused by…
renal tumor
smoking
high altitude
renal ischemia
PV
↑ RBC mass → ————– → CV disease
blood hyperviscosity
1/3 of PV patients have ——– or ——— episodes
thrombotic
hemorrhagic
Hct >60%
PV
PV factors affecting survival
- age
- abnormal karyotype
- leukocytosis
- history of thrombosis
Hgb & Hct diagnostic requirements for PV (male and female)
Male
Hct: >49%
Hgb: >16.5
Female
Hct: >48%
Hgb: >16.0
PV often shows —–lineage growth in BM
tri
EPO will be —– in PV
↓↓
nonspecific RBC morphology associated with PV
poik
targets
pencil cells
acanthocytes
most aggressive MPN
primary myelofibrosis
PMF survival
4-5 years
mutations common in PMF
JAK2
CALR
MPL
PB findings in PMF
teardrops
blasts
large plts