bcr/abl-negative, classic myeloproliferative disorders: Diagnosis and treatment

Essential thrombocythemia, polycythemia vera, and myelofibrosis with myelold metaplasia constitute the "classic" bcr/abl-negative myeloproliferative disorders (MPDs). Each of these MPDs represents a stem cell-derived clonal myeloprollferation with the respective features of thrombocytosis, erythrocytosis, and bone marrow fibrosis. Unlike with cases of chronic myeloid leukemia, in which the bcr/abl mutation is Invariably detected, current diagnosis of essential thrombocythemia, polycythemia vera, and myelofibrosis with myelold metaplasia Is based on a consensus-driven set of clinical and laboratory criteria that have undergone substantial modification In recent times. The recent discovery of a recurrent activating Janus tyrosine kinase (JAK2) mutation (JAK2^V617F) In all 3 classic MPDs offers another opportunity for refining current diagnoses and disease classifications. In this article, we outline contemporary diagnostic algorithms for each of these disorders and provide an evidence-based approach to management.