title: Myeloproliferative neoplasms: trends in incidence, prevalence and survival in Norway.
abstract: BACKGROUND
  Polycythemia vera (PV), essential thrombocythemia (ET) and myelofibrosis (MF) are clonal disorders collectively named as myeloproliferative neoplasms (MPN). Published data on epidemiology of MPN after the discovery of the JAK2 mutation and the 2008 WHO classifications are scarce. We aimed to study the incidence rates, prevalence and survival of MPN in Norway during the period 1993-2012.
  
  
  METHODS
  We identified 2453 persons diagnosed with MPN from the Cancer Registry of Norway between 1993 and 2012. We report age-adjusted incidence rates, prevalence, relative survival and standardised mortality rates.
  
  
  RESULTS
  The overall age-adjusted yearly incidence rate of PV increased from 0.4/10⁵ to 0.7/10⁵, ET increased from 0.3/10⁵ to 1.0/10⁵ and MF from 0.2/10⁵ to 0.5/10⁵. Prevalence of PV, ET and MF was 9.2, 8.6 and 3.0 per 10⁵ inhabitants, respectively. The five-year relative survival (RS) of ET and PV was slightly reduced with no improvement. The five-year RS of MF was 58.1% (2008-2012). Standardised mortality rate (SMR) was 1.9 (95% CI 1.2 - 2.7).
  
  
  CONCLUSIONS
  The incidence rates of ET, PV and MF doubled and tripled during the years 2007-2012 as compared to 1995-2006. This increment in incidence rates may be related to identification of the JAK2 mutation and the derived 2008 WHO guidelines for MPN. The RS was only slightly reduced in PV and ET, but was substantially reduced in MF.
authors: Dept of Medicine, Ostfold Hospital, Norway.
authors: Christina
authors: C
authors: Roaldsnes
authors: Dept of Medicine, Ostfold Hospital, Norway.|Oslo Centre for Biostatistic and Epidemiology, University of Oslo, Oslo University Hospital, Norway.
authors: René
authors: R
authors: Holst
authors: Odense University Hospital, Odense, Denmark.
authors: Henrik
authors: H
authors: Frederiksen
authors: Dept of Medicine, Ostfold Hospital, Norway.|Institute of Clinical Medicine, University of Oslo, Norway.
authors: Waleed
authors: W
authors: Ghanima
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009196:Myeloproliferative Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000401:mortality; D009664:Norway / Q000453:epidemiology; D011159:Population Surveillance; D015995:Prevalence; D012042:Registries
keywords: essential thrombocythemia; myelofibrosis; myeloproliferative neoplasms; polycythemia vera