Ruxolitinib in Primary Myelofibrosis and Secondary to Essential Thrombocythemia or Polycythemia Vera

The study is observational multicenter retrospective and prospective cohort study of patients with primary or secondary myelofibrosis who have initiated therapy with ruxolitinib, prescribed as part of the normal course of care and completely independent of study participation. Laboratory tests and histological, cytogenetic, molecular, and radiological investigations performed by the patient and collected for study will be conducted in accordance with clinical practice, independent of the patient's participation in the study. In particular. data on systemic symptoms and splenomegaly will be collected at diagnosis and disease reassessments performed in the context of normal clinical practice. The minimum planned duration of individual patient observation is 3 months and the planned duration of the study is 10 years.