title: Polycythemia vera: new clinicopathologic perspectives.
abstract: BACKGROUND
  Polycythemia vera (PV) is a clonal myeloproliferative disease characterized by an erythroid dominant trilineage proliferation of hematopoietic precursor cells. Classified as a chronic myeloproliferative disease, PV represents a histopathologic spectrum of 2 recognized stages, the polycythemic and postpolycythemic phase. The clinical manifestations of hemorrhage, thrombosis, and increased red cell mass are directly related to primary bone marrow dysfunction. Prognosis is strongly associated with thrombosis risk and disease progression; thus, treatment is directed toward minimizing coagulopathic complications and preventing leukemic transformation. Recently, a specific point mutation in the Janus kinase 2 (JAK2) gene was described in a majority of PV patients. The potential diagnostic and/or prognostic value of JAK2V617F is discussed.
  
  
  OBJECTIVE
  To review important developments from the recent and historical literature. Modern diagnostic criteria and emerging molecular findings are emphasized.
  
  
  METHODS
  A comprehensive review was performed of the relevant literature indexed in PubMed (National Library of Medicine) and referenced medical texts.
  
  
  CONCLUSIONS
  Modified clinical, histologic, and laboratory criteria have clarified the diagnosis of PV. Also, continuing studies on the recently discovered JAK2V617F gene mutation may significantly improve our understanding of PV pathogenesis and facilitate its medical management.
authors.affiliation: Department of Pathology, The Methodist Hospital, Houston, Tex 77030, USA.
authors.forename: Ming
authors.initials: M
authors.lastname: Cao
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Olsen
authors.forename: Youli
authors.initials: Y
authors.lastname: Zu
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D001853:Bone Marrow / Q000473:pathology; D004911:Erythrocyte Volume; D006470:Hemorrhage / Q000209:etiology / Q000473:pathology; D006801:Humans; D053614:Janus Kinase 2; D017354:Point Mutation; D011087:Polycythemia Vera / Q000150:complications / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D011505:Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D013927:Thrombosis / Q000209:etiology / Q000473:pathology
chemical_list: D015415:Biomarkers; D011518:Proto-Oncogene Proteins; D011505:Protein-Tyrosine Kinases; C507924:JAK2 protein, human; D053614:Janus Kinase 2