<unk>   are a group of eight disease subtypes of the bone marrow in which excess cells are produced.<unk>  may be classified according to the World Health Organization into eight subtypes, including polycythemia vera, essential thrombocythemia, primary myelofibrosis, chronic myelogenous leukemia, chronic neutrophilic leukemia, chronic eosinophilic leukemia,<unk>  not otherwise specified, and mastocytosis.They are related to, or may evolve into, myelodysplastic syndrome and acute myeloid leukemia, although the<unk>  diseases on the whole have a much better prognosis than these conditions. Clinical and pathologic features in the<unk> s are due to dysregulated proliferation and expansion of myeloid progenitors in the bone marrow, resulting in altered populations of granulocytes, erythrocytes, or platelets in the peripheral blood.<unk>  is caused by a mutational events in the BCR-ABL, ''Janus kinase 2'' (JAK2), ''calreticulin'' (CALR), or<unk>  leukemia (MPL) genes. Patients may be asymptomatic at diagnosis. However, if symptoms present, symptoms of<unk>  include fever, fatigue, and bleeding. The mainstay of therapy for<unk>  is chemotherapy, cytoreduction, aspirin, and palliative care.
Myeloproliferative neoplasm
Immunoproliferative disorders
Lymphoproliferative disorders
Plasma cell disorder
Leukemoid reaction
Myelofibrosis
Congenital disorders of the bone marrow
Myelodysplastic syndrome