Table 1.

The 2008 WHO classification of chronic myeloid neoplasms

Category	Characteristics	Diseases
Myeloproliferative neoplasms	Effective maturation of RBC, WBC, and platelets	Chronic myelogenous leukemia, polycythemia vera, essential thrombocythemia, primary myelofibrosis, chronic neutrophilic leukemia, chronic eosinophilic leukemia, mastocytosis, unclassifiable myeloproliferative neoplasm
Myelodysplastic syndrome	Ineffective maturation of RBC, WBC or platelets with dysplastic features	Refractory cytopenia with unilineage dysplasia, refractory anemia with ring sideroblasts, refractory cytopenia with multilineage dysplasia, refractory anemia with excess sideroblasts, myelodysplastic syndrome with isolated deletion of chromosome 5q, unclassifiable myelodysplastic syndrome, refractory cytopenia of childhood
Myelodysplastic–myeloproliferative disorders	Hybrid dysplastic and proliferative features	Chronic myelomonocytic leukemia, juvenile myelomonocytic leukemia, atypical chronic myeloid leukemia, unclassifiable myelodysplastic– myeloproliferative, neoplasm