85 Primary Myelofibrosis Flashcards
(133 cards)
TRUE OR FALSE
The the fibrosis in PMF is secondary, not primary
TRUE
The the fibrosis in PMF is secondary, not primary
The only cancer in the medical lexicon not so designated; rather, it is named for an epiphenomenon in the extracellular matrix
PMF
Central pathologic change in PMF
Neoplastic (dysmorphic) megakaryocytopoiesis
Mutations in PMF
50% JAK2 gene
25% Calreticulin (CALR) gene
~5%Thrombopoietin receptor (C-MPL) gene
Percentage of triple-negative PMF
10%
In infants, the disorder can mimic the classic disease or show certain features but not others, such as ________________
Absence of hepatosplenomegaly
TRUE OR FALSE
In young and middle-age adults, PMF is similar to that in older subjects, although the proportion of indolent cases may be higher, and the disease occurs in boys twice as frequently as in girls.
FALSE
In young and middle-age adults, PMF is similar to that in older subjects, although the proportion of indolent cases may be higher, and the disease occurs in girls twice as frequently as in boys.
TRUE OR FALSE
In adults, the disease occurs with about equal frequency in men as in women.
TRUE
In adults, the disease occurs with about equal frequency in men as in women.
Exposure to high concentrations of __________ or __________________ preceded the development of PMF in a very small number of cases in the past.
Benzene
Very-high-dose ionizing radiation
Benzene in exposures greater than __________ is associated with an increased relative risk of acute myelogenous leukemia (AML) but not of chronic myelogenous leukemias.
40–200 ppm-years
TRUE OR FALSE
Most lymphocytes, and especially most long-lived T-lymphocytes are formed before acquired JAK2 V617F mutational event and are thus not part of PMF clone.
TRUE
Most lymphocytes, and especially most long-lived T-lymphocytes are formed before acquired JAK2 V617F mutational event and are thus not part of PMF clone.
JAK2 gene mutation in exon 12 account for _____ of PMF
~1%
JAK2 V617F is a dominant, gain-of-function mutation in the gene residing on chromosome _________
Chromosome 9p24
Percentage of JAK2 Mutation in:
PV:
PMF:
ET:
Percentage of JAK2 Mutation in:
PV: 98%
PMF: 60%
ET: 55%
Absent in most healthy individuals
A negative regulator of three important pathways in hematopoiesis—JAK2/STAT5, AKT, and MAPK—as well as in inflammation
LNK protein
Non-Driver Somatic Mutations that predict an inferior prognosis
ASXL1/SRSF2
Non-Driver Somatic Mutations associated with progression to AML from an MPN
RUNX1, TP53, NRAS, WT1, FLT3, IDH1/2, and TET2
High levels of fibroblastic factors __________________ resulted in intense fibrosis in animal models.
TGF-β 1 and platelet-derived growth factor [PDGF]
Increased ______________ was thought to be the principal cause of osteosclerosis
Osteoprotegerin
In PMF, it is the most prominent alteration in this clonal myeloid disease and is responsible for most of its major manifestations
Neoplastic megakaryopoiesis
Constitutive mobilization and circulation of CD34+ cells are prominent features of the clonal expansion.
TRUE OR FALSE
Microvessel density and marrow blood flow are increased in patients with PMF.
TRUE
Microvessel density and marrow blood flow are increased in patients with PMF.
Causes of anemia in PMF
- Decreased erythropoiesis
- Shortened red cell survival
- Effects of splenomegaly on the distribution of red cells in the circulation
- Hemolysis
Synonym for PMF
Megakaryocytic myelosis
Chronic megakaryocytic leukemia
Four of the five major types of collagen are present in normal marrow:
- Type I in bone
- Type III in blood vessels
- Types IV and V in basement membranes