Comparison of Polystemia Vera Patients Diagnosed Before and After the Updated Diagnostic Criteria

Polycythemia vera is a chronic, clonal and progressive myeloproliferative disease characterized by leukocytosis, thrombocytosis and splenomegaly with increased erythroid series. In this study, we aimed to compare the clinical and laboratory features of patients diagnosed with PV according to the 2008 and 2016 WHO diagnostic criteria and the complications that developed during follow-up, and to retrospectively evaluate the impact of the change in diagnostic criteria on real life. A total of 100 polycythemia vera patients with positive JAK2-V617F mutation were enrolled in the study, 50 between 2011-2015 and 50 between 2016-2020. When the two groups were compared in terms of laboratory values at the time of diagnosis, hemoglobin, hematocrit and red blood cell count were significantly higher in the group diagnosed before 2016 (p=0.036). When patients were evaluated for complications of thrombosis, hemorrhage, progression to myelofibrosis, leukemic transformation, and transformation of myelodysplastic syndrome at last follow-up, it was found that 19 (38%) patients in the pre-2016 group and 5 (10%) patients in the post-2016 group developed complications (p=0.002). The number of patients who developed a myelofibrosis complication was significantly higher in the pre-2016 group (p=0.006). The number of patients who developed thrombosis was higher in the pre-2016 group, but the difference did not reach a statistically significant level (p=0.055). About other complications, there was no difference between the two groups (p > 0.05). In summary, our study found a significant difference only in the number of patients with myelofibrosis complications. Further studies with more patients will be needed to determine the impact of the 2016 change in diagnostic criteria on other complications.