Myelodysplastic Syndrome
Epidemiology
Etiology
Physiology
Diagnosis
WHO Classification of Myelodysplastic Syndromes [MEDLINE]
Refractory Anemia (RA)
- Blood Findings
- Bone Marrow Findings
- Eythroid Dysplasia Alone
- <5% Blasts
- <15% Ringed Sideroblasts
Refractory Cytopenia with Unilineage Dysplasia
- Epidemiology: accounts for <5% of myelodysplastic syndrome cases
- Blood Findings: one of the following
- Refractory Anemia (see Anemia, Anemia)
- Refractory Neutropenia
- Refractory Thrombocytopenia
- Bone Marrow Findings
Refractory Anemia with Ringed Sideroblasts (RARS)
- Epidemiology: accounts for <5% of myelodysplastic syndrome cases
- Blood Findings
- Bone Marrow Findings
- Erythroid dysplasia alone
- < 5% blasts
- ≥ 15% ringed sideroblasts
Refractory Cytopenia with Multilineage Dysplasia (RCMD)
- Epidemiology: accounts for 70% of myelodysplastic syndrome cases
- Blood Findings
- Cytopenias (bicytopenia or pancytopenia)
- no or rare blasts
- no Auer rods
- < 1 billion monocytes per liter
- Bone Marrow Findings
- Dysplasia in ≥ 10% of cells in ≥ 2 myeloid cell lines
- < 5% blasts
- No Auer rods
- <15% ringed sideroblasts
Refractory Cytopenia with Multilineage Dysplasia and Ringed Sideroblasts
- Epidemiology: accounts for 70% of myelodysplastic syndrome cases
- Blood Findings
- Cytopenias (bicytopenia or pancytopenia)
- No or rare blasts
- No Auer rods,
- < 1 billion monocytes per liter
- Bone Marrow Findings
- Dysplasia in ≥ 10% of cells in ≥ 2 myeloid cell lines
- < 5% blasts
- No Auer rods
- ≥ 15% ringed sideroblastsxx
Refractory Anemia with Excess Blasts-1 (RAEB-1)
- Epidemiology: accounts for 25% of myelodysplastic syndrome cases
- Blood Findings
- Cytopenias
- < 5% blasts
- No Auer rods
- <1 billion monocytes per liter
- Bone Marrow Findings
- Unilineage or multilineage dysplasia
- 5—9% blasts
- No Auer rods
Refractory Anemia with Excess Blasts-2 (RAEB-2)
- Epidemiology: accounts for 25% of myelodysplastic syndrome cases
- Blood Findings
- Cytopenias
- 5—19% blasts
- Occasional Auer rods
< 1 billion monocytes per liter
- Bone Marrow Findings
- Unilineage or multilineage dysplasia
- 10—19% blasts
- Occasional Auer rods
Myelodysplastic Syndrome with Isolated del(5q)
- Epidemiology: accounts for 5% of myelodysplastic syndrome cases
- Blood Findings
- Anemia (see Anemia, Anemia)
- <5% Blasts
- Platelet count normal to increased
- Bone Marrow Findings
- Normal-to-increased megakaryocytes with hypolobated nuclei
- < 5% blasts
- No Auer rods
- Isolated del (5 q)
Myelodysplastic Syndrome, Unclassified (MDS-U)
- Epidemiology: accounts for <5% of myelodysplastic syndrome cases
- Blood Findings
- Cytopenias
- No or rare blasts
- No Auer rods
- Bone Marrow Findings
- Unilineage dysplasia in granulocytes or megakaryocytes
- <5% blasts
- No Auer rodsx
Clinical Manifestations
Pulmonary Manifestations
- Pulmonary Hypertension (see Pulmonary Hypertension, Pulmonary Hypertension)
- Early Chest Series of Unexplained Pulmonary Hypertension in Myeloproliferative Disorders (2001) [MEDLINE]: 14/26 patients had platelet counts >600k
- 12 patients had diagnosis of myeloid metaplasia with myelofibrosis
- 5 patients had diagnosis of essential thrombocytosis
- 6 patients had diagnosis of polycythemia vera
- 2 patients had diagnosis of myelodysplastic sydrome
- xxx
- xxx
- xxx
- xxx
Other Manifestations
Treatment
References
- Unexplained pulmonary hypertension in chronic myeloproliferative disorders. Chest. 2001 Sep;120(3):801-8 [MEDLINE]
- The World Health Organization (WHO) classification of the myeloid neoplasms. Blood. 2002 Oct 1;100(7):2292-302 [MEDLINE]
- Incidence of pulmonary hypertension in patients with chronic myeloproliferative disorders. Haematologica 2004;89:245—7 [MEDLINE]
- Pulmonary hypertension in patients with chronic myeloproliferative disorders. Eur Respir J. 2010 Jun;35(6):1396-406. doi: 10.1183/09031936.00175909 [MEDLINE]
- Non-infectious pulmonary complications of myelodysplastic syndromes and chronic myeloproliferative disorders. Rev Mal Respir. 2011 Jun;28(6):e18-27. doi: 10.1016/j.rmr.2009.04.001. Epub 2011 Jun 8[MEDLINE]