The significance of bone marrow biopsy and JAK2V617F mutation in the differential diagnosis between the "early" prepolycythemic phase of polycythemia vera and essential thrombocythemia.
It has been suggested that polycythemia vera (PV) could be preceded by an "early" phase of the disease (e-PV), in which the increase in the red cell parameters is lower than required for a PV diagnosis. In this study, we compared the clinicopathologic and molecular features of 17 patients with e-PV with those of 14 patients with essential thrombocythemia (ET) and 19 with PV. The results for e-PV were more similar to those for PV than for ET. In fact, patients with e-PV were characterized by an increase in the red cell parameters, splenomegaly (P<.05), and hepatomegaly (P=.038), together with hypercellular bone marrow due to increased erythropoiesis and granulopoiesis, associated with megakaryocytic hyperplasia, with pleomorphic aggregates (P<.001). The frequency of the JAK2V617F mutation was similar in e-PV (16 cases tested [100%]) and PV (18/19 [95%]) but was significantly lower (7/13 [54%]) in ET (P=.0007). We propose a diagnostic algorithm helpful to distinguish ET from the early prepolycythemic phase of PV.
Gianelli
Umberto
U
Pathology Unit, Department of Medicine, Surgery, and Odontology, University of Milan, San Paolo Hospital, Milan, Italy.
Iurlo
Alessandra
A
Vener
Claudia
C
Moro
Alessia
A
Fermo
Elisa
E
Bianchi
Paola
P
Graziani
Daniela
D
Radaelli
Franca
F
Coggi
Guido
G
Bosari
Silvano
S
Deliliers
Giorgio Lambertenghi
GL
Zanella
Alberto
A
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001853:Bone Marrow / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011087:Polycythemia Vera / Q000175:diagnosis*; D012189:Retrospective Studies; D013920:Thrombocythemia, Essential / Q000175:diagnosis*
C507924:JAK2 protein, human; D053614:Janus Kinase 2