TABLE 2

Polycythemia vera: 2016 revision to the 2008 World Health Organization diagnostic criteria

Major criteria

  1. Hemoglobin > 16.5 g/dL in men, > 16.0 g/dL in women; or hematocrit > 49% in men, > 48% in women; or increased red cell mass (> 25% above mean normal predicted value)

  2. Bone marrow biopsy showing hypercellularity for age with trilineage growth (panmyelosis) with prominent erythroid, granulocytic, and megakaryocytic proliferation with pleomorphic, mature megakaryocytes (differences in size)

  3. JAK2 V617F or JAK2 exon 12 mutation

Minor criterion
 Subnormal serum erythropoietin level
Diagnosis requires all three major criteria, or the first two major criteria and the minor criteriona

  • ↵a Criterion 2 (bone marrow biopsy) may not be required in cases with sustained absolute erythrocytosis: hemoglobin levels > 18.5 g/dL in men (hematocrit 55.5%) or > 16.5 g/dL in women (hematocrit 49.5%) if major criterion 3 and the minor criterion are present. However, initial myelofibrosis (present in up to 20% of patients) can only be detected by performing a bone marrow biopsy. This finding may predict a more rapid progression to overt myelofibrosis (post-polycythemia vera myelofibrosis).

  • Republished with permission of the American Society of Hematology, from Arber DA, Orazi A, Hasserjian R, et al. The 2016 revision to the World Health Organization classification of myeloid neoplasms and acute leukemia. Blood 2016; 127:2391–2405.