Frequency of JAK2V617F, MPL and CALR driver mutations and associated clinical characteristics in a Norwegian patient cohort with myeloproliferative neoplasms.

Myeloproliferative neoplasms are hematological disorders characterized by increased production in one or more myeloid cell lines, associated with driver mutations in and genes. The aims of this study were to investigate the prevalence of these driver mutations in a Norwegian patient cohort with myeloproliferative neoplasms, and to assess whether the different mutations were associated with different clinical presentation and natural history.Results from 820 patients in whom analysis for V617F and had been performed at Haukeland University Hospital in the period 2014-2019 were retrieved and analyzed together with clinical variables related to diagnosis, hematological blood parameters and complications, obtained from patient records.We identified 182 cases of myeloproliferative neoplasms: 78 with V617F, 28 with mutations, two with -mutations and 23 cases without a driver mutation. There was a lower prevalence of V617F mutation than expected in the polycythemia vera group, likely related to overdiagnosis. In patients with essential thrombocytosis, we found significantly higher levels of hemoglobin and erythrocyte volume fraction for V617Fmutated disease, and significantly higher levels of platelets and lactate dehydrogenase for mutated disease. Patients with V617Fmutated primary myelofibrosis had significantly higher levels of hemoglobin, and there was an increased number of smokers or former smokers in this group compared to patients with mutations.Except for a lower prevalence of V617Fmutation in polycythemia vera, the mutational distribution in our patient cohort was similar to previous findings in other populations. The novel finding of a higher prevalence of smokers in V617Fmutated primary myelofibrosis warrants further investigation.