Prospective validation of the dutch myeloproliferative neoplasm symptom assessment form (MPN-SAF: Dutch) in 236 MPN patients

Background. Myeloproliferative Neoplasma (MPN) give rise to specific symptoms generally not assessed by validated Quality-of-Life (QoL) Questionnaires. In view of the reported high impact of these specific symptoms on QoL and social participation, detailed information on the effect of new developed therapies is of importance. The MPNSymptom Assessment Form (MPN-SAF) is a concise instrument of patient reported outcomes designed to assess the unique spectrum of symptoms present in patients with MPN. Aims. We sought to validate this instrument and to assess symptoms in a representative Dutch population of patients with myelofibrosis (MF), essential thrombocythemia (ET) and polycythemia vera (PV). Methods. The MPN-SAF was translated in Dutch by one of the authors fluent in both languages, confirmed by one member of the Dutch patient MPN Foundation and sent to all members of the Dutch MPN Foundation. The Dutch EORTC-QLQ-C30 was co-administered for validation purposes. In addition, data were compared to a cohort of 102 USA MPN patients completing the MPN-SAF English. Results. The questionnaires were sent to 874 patients. The response rate was 39%. A total of 236 patients were included in the analysis (ET [n=72; 30.5%)], PV [n=119; 50,4%] and MF [n=45; 19,1%]), as 104 questionnaires (34%) had not been completely filled out. The distribution of the type of MPN (19.6%, 22.5% and 57.8% respectively, p