Myelodysplastic syndromes (MDS) are a group of rare blood cancers that occur when the blood-forming cells in the bone marrow become abnormal. This leads to low numbers of one or more types of blood cells, and MDS is considered a type of cancer. There are several different types of MDS, based on how many types of blood cells are affected and other factors. MDS tends to affect people over age 60, and its more common in men than in women. Common risk factors for MDS include age, gender, smoking, exposure to radiation and benzene, and past treatment with chemotherapy or radiation therapy for cancer. Symptoms of MDS include shortness of breath and feeling tired.

In about 1 in 3 patients, MDS can progress to a rapidly growing cancer of bone marrow cells called acute myeloid leukemia (AML) . The risk of this happening depends on what kind of MDS a person has and the number of normal and abnormal blood cells they have. MDS that develops after use of cancer chemotherapy or radiation is called “secondary MDS” and is usually associated with multiple chromosome abnormalities in cells in the bone marrow.

Treatments for MDS include blood transfusions, medications to stimulate blood cell production, chemotherapy, and bone marrow transplant. The choice of treatment depends on the type of MDS, the severity of the disease, and the persons overall health.