biostudies-literatureMasarova LNational Cancer InstituteNCI NIH HHS257-263https://www.ebi.ac.uk/biostudies/studies/S-EPMC5814342biostudies-literatureUnknown100(3)Severe thrombocytopenia (platelets <50 × 10⁹ /L) is associated with very poor outcome of patients with myelofibrosis (MF). As patients with primary myelofibrosis (PMF) differ from patients with postessential thrombocythemia (PET-MF) and postpolycythemia vera myelofibrosis (PPV-MF), we aimed to evaluate the significance of low platelets among these patients. We present clinical characteristics and outcome of patients with either PMF, PPV-MF, or PET-MF, and thrombocytopenia who presented to our institution between 1984 and 2015. Of 1269 patients (877 PMF, 212 PPV-MF, 180 PET-MF), 11% and 14% had platelets either <50 × 10⁹ /L or between 50-100 × 10⁹ /L, respectively. Patients with platelets <50 × 10⁹ /L were most anemic and transfusion dependent, haEuropean journal of haematologySignificance of thrombocytopenia in patients with primary and postessential thrombocythemia/polycythemia vera myelofibrosis.PMC5814342CA016672P30 CA016672Pierce SMasarova LKantarjian HPemmaraju NVerstovsek SDaver NAlhuraiji ACortes JBose PfalseSignificance of thrombocytopenia in patients with primary and postessential thrombocythemia/polycythemia vera myelofibrosis.Severe thrombocytopenia (platelets <50 × 10⁹ /L) is associated with very poor outcome of patients with myelofibrosis (MF). As patients with primary myelofibrosis (PMF) differ from patients with postessential thrombocythemia (PET-MF) and postpolycythemia vera myelofibrosis (PPV-MF), we aimed to evaluate the significance of low platelets among these patients. We present clinical characteristics and outcome of patients with either PMF, PPV-MF, or PET-MF, and thrombocytopenia who presented to our institution between 1984 and 2015. Of 1269 patients (877 PMF, 212 PPV-MF, 180 PET-MF), 11% and 14% had platelets either <50 × 10⁹ /L or between 50-100 × 10⁹ /L, respectively. Patients with platelets <50 × 10⁹ /L were most anemic and transfusion dependent, ha2018-01-01T00:00:00Z2018 Mar2025-04-05T12:16:35.797Z2019-08-04T07:05:56ZS-EPMC58143422922642610.1111/ejh.13005