title: Validation of the revised 2008 WHO diagnostic criteria in 75 suspected cases of myeloproliferative neoplasm.
abstract: The objective of this study was to validate the recently revised 2008 WHO diagnostic criteria of myeloproliferative neoplasms (MPN) together with the analysis of correlation of JAK2 (Janus kinase 2)-V617F mutant allele burden with clinical/laboratory findings on each patient. We made a diagnosis of 75 suspected MPN patients based on both diagnostic criteria of the 2001 WHO classification and the revised 2008 WHO classification, and found that both criteria show a quite similar diagnostic power except for two patients (idiopathic erythrocytosis (IE) and thrombocytosis) who were diagnosed as essential thrombocythemia by the 2008 WHO criteria. From JAK2-V617F analysis, hemoglobin and hematocrit values were significantly higher and platelet count was lower in JAK2-V617F high allele burden group than JAK2-V617F middle allele burden group. Mutant allele burden of polycythemia vera (PV) group was higher than that of essential thrombocythemia group. Therefore, the amount of mutant allele seemed to define the disease phenotypes. We further found a PV case presenting a rare type of JAK2-exon12 mutation. In contrast, IE presented a good prognosis unlike MPN. Hereafter, the 2008 WHO criteria with JAK2 gene analysis are useful for precise diagnosis of MPN and the patients with erythrocytosis.
authors.affiliation: Department of Laboratory Medicine, Kawasaki Medical School, Okayama, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Kondo
authors.forename: Nanako
authors.initials: N
authors.lastname: Okuno
authors.forename: Hiromu
authors.initials: H
authors.lastname: Naruse
authors.forename: Mitsuyo
authors.initials: M
authors.lastname: Kishimoto
authors.forename: Taizo
authors.initials: T
authors.lastname: Tasaka
authors.forename: Takayuki
authors.initials: T
authors.lastname: Tsujioka
authors.forename: Akihito
authors.initials: A
authors.lastname: Matsuoka
authors.forename: Takashi
authors.initials: T
authors.lastname: Sugihara
authors.forename: Yumi
authors.initials: Y
authors.lastname: Tohyama
authors.forename: Kaoru
authors.initials: K
authors.lastname: Tohyama
mesh_terms: D000328:Adult; D000368:Aged; D003933:Diagnosis; D006403:Hematologic Tests; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics; D008875:Middle Aged; D009154:Mutation; D009196:Myeloproliferative Disorders / Q000145:classification / Q000175:diagnosis*; D011086:Polycythemia; D011087:Polycythemia Vera; D017410:Practice Guidelines as Topic / Q000592:standards*; D013920:Thrombocythemia, Essential; D013922:Thrombocytosis; D014944:World Health Organization
chemical_list: D053614:Janus Kinase 2