A myelodysplastic syndrome (MDS) is one of a group of cancers in which immature blood cells in the bone marrow do not mature, and as a result, do not develop into healthy blood cells. Early on, no symptoms typically are seen. Later, symptoms may include feeling tired, shortness of breath, bleeding disorders, anemia, or frequent infections. Some types may develop into acute myeloid leukemia.Risk factors include previous chemotherapy or radiation therapy, exposure to certain chemicals such as tobacco smoke, pesticides, and benzene, and exposure to heavy metals such as mercury or lead. Problems with blood cell formation result in some combination of low red blood cell, platelet, and white blood cell counts. Some types have an increase in immature blood cells, called blasts, in the bone marrow or blood. The types of MDS are based on specific changes in the blood cells and bone marrow.Treatments may include supportive care, drug therapy, and hematopoietic stem cell transplantation. Supportive care may include blood transfusions, medications to increase the making of red blood cells, and antibiotics. Drug therapy may include the medications lenalidomide, antithymocyte globulin, and azacitidine. Certain people can be cured with chemotherapy followed by a stem-cell transplant from a donor.About seven per 100,000 people are affected, with about four per 100,000 people newly acquiring the condition each year. The typical age of onset is 70 years. The outlook depends on the type of cells affected, the number of blasts in the bone marrow or blood, and the changes present in the chromosomes of the affected cells.
The early identification, characterization and classification of this disorder were problematical, and the syndrome went by many names until the 1976 FAB classification was published and popularized the term MDS. Michael Brecker
Roald Dahl
Nora Ephron
Joe Farrell
Pat Hingle
John Kirby (attorney)
Joe Morgan (Cincinnati Reds player)
Paul Motian
James W. Nance
Robin Roberts (newscaster)
Carl Sagan
Susan Sontag
Fred Willard

French-American-British (FAB) classification
In 1974 and 1975, a group of pathologists from France, the US, and Britain produced the first widely used classification of these diseases. This French-American-British classification was published in 1976, and revised in 1982. It was used by pathologists and clinicians for almost 20 years. Cases were classified into five categories:

(A table comparing these is available from the Cleveland Clinic.) See also
Chloroma
Myeloproliferative syndrome
Clonal hematopoiesis

References
External links

Myelodysplastic syndrome at Curlie
Fenaux, P., et al. (2014). Myelodysplastic syndromes: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up † Myelodysplastic syndromes: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Annals of Oncology 25(suppl 3): iii57–iii69.