Patient-Reported Outcomes in PHiladelphia-nEgative Cytogenetic mYeloproliferative Neoplasms (PROPHECY).

Inclusion Criteria: * Patients diagnosed with Polycythemia Vera (PV), Essential Thrombocythemia (ET) and Primary Myelofibrosis (pre-PMF, overt-PMF) and post-ET/post-PV Myelofibrosis (MF), (i.e. Philadelphia chromosome negative myeloproliferative neoplasm (MPN)) according to 2016 WHO classification. * Known IPSS/IPSET/DIPSS risk score category at time of initial diagnosis of PV, ET and PMF, respectively. * Initial diagnosis of MPN within one year before date of registration. * Having a full baseline PRO Evaluation completed. * Adult patients (≥ 18 years old). * Written informed consent provided. Exclusion Criteria: * Having any kind of psychiatric disorder or major cognitive dysfunction problems hampering a self-reported evaluation. * Not able to read and understand local language (i.e. Italian).