Rapid Development of Unclassified Myeloid Lineage Acute Leukaemia With Trisomy 6 and U2AF1 Mutation.

We present a case of acute clonal bone marrow 98% infiltration of atypical myeloid cells with borderline hypogranular/agranular promyelocytes/myelocytes and occasional blast cells maturity, which also formed extramedullary tumours in the chest wall, with isolated trisomy of chromosome 6 and pathogenic variant U2AF1 (S34F) that escapes established acute myeloid leukaemia (AML) diagnostic criteria according to the World Health Organization (WHO) classification. Following standard daunorubicin and cytarabine induction therapy, the disease progressed with the appearance of a previously undetected clone of leukaemic cells with a distinct immunophenotype demonstrating monocytoid differentiation and clonal evolution to a hypo-tetraploid karyotype with an average number of 84 chromosomes and new pathogenic NRAS and ZRSR2 mutations. The patient reactivated refractory disseminated intravascular coagulation (DIC) leading to a progressive supratentorial hematoma and finally cardiac arrest.

Analysis of Predictive Factors for Early Response to Ruxolitinib in 320 Patients with Myelofibrosis From the Polish Adult Leukemia Group (PALG) Registry.

Introduction: Ruxolitinib is widely used in myelofibrosis (MF). However, some patients do not optimally respond and require more efficacious treatment. Our analysis aimed to establish predictors of ruxolitinib response.