Learning About Myelodysplastic Syndromes (MDS)

What are myelodysplastic syndromes (MDS)?

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.

What puts you at risk for MDS?

Anyone can get MDS. But some people are more likely to develop it. Things that can raise your risk include:

Older age. MDS is rare in people younger than 50. It is most common in people in their 70s or 80s.
Being biologically male. Men are diagnosed with MDS more often than women. The reason is not fully known. Talk to your doctor if you have questions about your risk.
Past cancer treatment. People who have had certain chemotherapy or radiation treatments for cancer are at higher risk. But only a small number of people who get cancer treatment develop MDS later.
Smoking. Harmful chemicals from smoke can enter the blood and travel through the body, damaging many tissues.
Environmental exposure. Long-term exposure to benzene and other chemicals used in the petroleum, rubber, and farming industries can increase your risk.
Some genetic conditions. Conditions such as Fanconi anemia, Down syndrome, Bloom syndrome, and others can increase the risk of MDS.
Family health history. In some families, MDS is more common because of a gene change. But sometimes the cause is unknown.

What are the symptoms of MDS?

Some people with MDS have no symptoms at first. Symptoms are caused by low levels of blood cells.

Symptoms of low red blood cells (anemia) can include:

Feeling tired, weak, or short of breath.
Looking pale.

Symptoms of low white blood cells (neutropenia) can include:

Getting infections more often.
Getting infections that are more serious or long-lasting.

Symptoms of low platelets (thrombocytopenia) can include:

Bruising or bleeding easily.
Getting a bloody nose often.
Having bleeding gums or small purple spots on your skin (petechiae).

How is MDS diagnosed?

You may have one or more of these tests:

Complete blood count (CBC). This is a simple blood test. It measures the number of each type of blood cells.
Blood smear. The sizes and shapes of your blood cells are looked at under a microscope.
Bone marrow biopsy. A small sample is taken from your bone to check the cells in the marrow.
Genetic tests. These look for chromosome changes in your cells.

How is MDS treated?

Treatment depends on the type of MDS and your age, health, and symptoms. Treatments include:

Blood transfusions. These are done to give your body more healthy blood cells.
Growth factor medicines. These help your body make more blood cells.
Antibiotics. These medicines are used to treat infections.
Chemotherapy (chemo). Chemo medicines such as azacitidine, decitabine, or lenalidomide can help slow MDS.
Stem cell (bone marrow) transplant. This can help replace diseased cells with healthy ones. But it's not an option for all people and may not work well with some types of MDS.

New treatments are being tested in clinical trials. You can learn about them at clinicaltrials.gov or talk with your doctor. You can ask if there is a trial you may be able to join.