High levels of circulating CD34 cells, dacrocytes, clonal hematopoiesis, and JAK2 mutation differentiate myelofibrosis with myeloid metaplasia from secondary myelofibrosis associated with pulmonary hypertension.
We studied 25 patients with myelofibrosis with myeloid metaplasia and 19 patients with secondary myelofibrosis associated with pulmonary hypertension (PH). In these 2 groups, we compared the peripheral-blood CD34 count, the clonality of granulocytes and platelets in peripheral blood, the mutational status of the JAK2 kinase gene, and the morphology of the peripheral blood and bone marrow. We found that the following were distinctive features of myelofibrosis with myeloid metaplasia but not of secondary myelofibrosis due to PH: high circulating CD34 cell count, the presence of clonal platelets and granulocytes and of peripheral-blood dacrocytes, and a JAK2 1849G>T (V617F) mutation. We conclude that these are intrinsic features of clonal progenitors present in patients with myelofibrosis due to myeloproliferative disorders and that these features are not due to the abnormal marrow architecture seen in secondary myelofibrosis.
Popat
Uday
U
Hematology Division, University of Utah, 30 North 1900 East, 4C416 SOM, Salt Lake City, 84132-2408, USA.
Frost
Adaani
A
Liu
Enli
E
Guan
Yongli
Y
Durette
April
A
Reddy
Vishnu
V
Prchal
Josef T
JT
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000378:metabolism; D001483:Base Sequence; D001772:Blood Cell Count; D004247:DNA / Q000235:genetics; D003937:Diagnosis, Differential; D005260:Female; D006410:Hematopoiesis; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications*; D053614:Janus Kinase 2; D008297:Male; D008875:Middle Aged; D009154:Mutation; D055728:Primary Myelofibrosis / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000235:genetics; D011446:Prospective Studies; D011505:Protein-Tyrosine Kinases / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000235:genetics
D018952:Antigens, CD34; D011518:Proto-Oncogene Proteins; D004247:DNA; D011505:Protein-Tyrosine Kinases; C507924:JAK2 protein, human; D053614:Janus Kinase 2