Chronic Myeloproliferative Disorders Treatment (PDQ®): Treatment - Health Professional Information [NCI] - General Information About Chronic Myeloproliferative Disorders
The chronic myeloproliferative disorders consist of chronic myelogenous leukemia, polycythemia vera (p. vera), primary myelofibrosis, essential thrombocythemia, chronic neutrophilic leukemia, and chronic eosinophilic leukemia. All of these disorders involve dysregulation at the multipotent hematopoietic stem cell (CD34), with one or more of the following shared features:
Overproduction of one or several blood elements with dominance of a transformed clone.
Patients with p. vera and essential thrombocythemia have marked increases of red blood cell and platelet production, respectively. Treatment is directed at reducing the excessive numbers of blood cells. Both p. vera and essential thrombocythemia can develop a spent phase late in their courses that resembles primary myelofibrosis with cytopenias and marrow hypoplasia and fibrosis.[1,2,3] A specific point mutation in one copy of the Janus kinase 2 gene (JAK2), a cytoplasmic tyrosine kinase, on chromosome 9, which causes increased proliferation and survival of hematopoietic precursors in vitro, has been identified in most patients with p. vera, essential thrombocythemia, and idiopathic myelofibrosis.[4,5,6,7,8,9] Researchers are pursuing specific targeting of this aberrant protein.
Sedation may be considered for comfort.
Patients with advanced cancer or near the end of life may have:
A lot of emotional distress and physical pain.
Difficult and painful breathing.
Confusion (especially when body systems begin to fail).
Sedation can be given to ease these conditions. This is called palliative sedation. Deciding to use palliative sedation may be difficult for the family as well as the patient. The patient and family can get support from the health care team and...
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