Myelodysplastic syndromes (MDS) are types of cancer that affect the blood and bone marrow. Your bone marrow is the soft tissue inside bones that makes blood cells. Your blood cells have different roles. Red blood cells carry oxygen. White blood cells fight infection. Platelets help stop bleeding.
With MDS, the bone marrow makes blood cells that are not healthy. These cells may not grow as they should, or they may die too soon. This can cause low numbers of blood cells.
There are different types of MDS. The type is determined by how the blood cells look, if there are gene changes, and other factors. Knowing the type helps your care team choose your treatment options.
MDS happens most often in adults over age 65. For some people, MDS can stay stable for years. For about 1 in 3 people (30%), it can get worse over time and turn into a fast-growing blood cancer called acute myeloid leukemia (AML). Your doctor will check your blood and bone marrow regularly to watch for any changes.