Myelodysplastic syndromes (MDS) are a group of conditions that cause problems with new blood cell production. With MDS, blood cells in the bone marrow are abnormal, which leads to fewer healthy red blood cells, white blood cells, and platelets.

Having too few red blood cells causes symptoms of anemia, such as shortness of breath and fatigue. A lack of white blood cells can also lead to more frequent infections. Having too few platelets increases the risk of bruising and bleeding.

There are six types of MDS. The types are based on which blood cells are affected and how abnormal those cells look under a microscope.

MDS is one of the most common blood cancers. Between 60,000 and 170,000 people in the United States live with this condition. Up to 20,000 people in the United States are diagnosed with MDS each year.

Experts don’t know exactly what causes MDS. The condition is more common in women and in people who:

  • are over 50 years of age
  • have had chemotherapy to treat cancer
  • have a history of smoking
  • have a family history of MDS or inherited conditions like Fanconi anemia or Diamond Blackfan anemia
  • have been exposed to chemicals such as benzene

A diagnosis can take time because MDS progresses slowly over many months to years. It’s also easy to mistake for leukemia.

Often MDS doesn’t cause any symptoms in its early stages. Doctors sometimes discover low blood cell counts while doing blood tests for another reason. A bone marrow aspiration and bone marrow biopsy confirm the diagnosis.

About 1 in 3 people with MDS develop acute myeloid leukemia (AML), a type of blood cancer. Your likelihood of progressing to AML depends on the type of MDS you have.

Doctors divide MDS into lower and higher risk types based on the number of abnormal blood cells in bone marrow, as well as other factors. Around 1 in 4 people with MDS have the high risk type. High risk MDS is more likely to turn into AML than low risk MDS.

Racial, ethnic, and gender differences exist in MDS diagnosis and care.

A 2022 study found that non-Hispanic white people had the highest likelihood of getting MDS compared with Hispanic and Black people. But in people under age 50, the rate of MDS was higher in Black people. Black people also had higher survival rates than Hispanic and non-Hispanic white people.

Women are diagnosed with MDS at a slightly younger age than men, according to a 2021 study. Women and men also typically have different gene mutations. And women with lower risk MDS have higher survival rates than men, but not women with higher risk MDS.

An MDS care team includes a few different types of specialists, such as:

  • oncologists
  • hematologists
  • bone marrow transplant specialists
  • physician assistants (PAs)
  • nurse practitioners
  • nurses
  • social workers
  • dietitians

There are three main types of treatments for MDS.

Supportive care

These treatments relieve symptoms caused by low blood cell counts and help you feel better. Supportive care includes blood transfusions and growth factors to boost blood cell counts, and antibiotics to prevent or treat infections.

Drug therapy

A few medicines slow MDS progression. These include:

  • lenalidomide (Revlimid), for a specific MDS subtype (deletion 5q cytogenetic abnormality)
  • immune-suppressing medications like antithymocyte globulin (ATG)
  • azacitidine (Vidaza) and decitabine (Dacogen) to help the bone marrow make new, healthy blood cells
  • Inqovi, a pill that combines decitabine and cedazuridine, for adults with MDS

Chemotherapy with a stem cell transplant

Chemotherapy kills the abnormal blood cells in bone marrow. After chemotherapy, you get stem cells taken from your own blood or bone marrow, or from a donor’s bone marrow, to replace them.

MDS affects your body’s ability to make new, healthy red blood cells, white blood cells, and platelets. How quickly it progresses and whether it turns into AML depends on the type of MDS you have. Higher risk MDS is more likely to turn into AML than lower risk MDS.

Symptoms like fatigue, shortness of breath, bleeding or bruising, and infections can happen when blood cell counts drop.

Supportive treatments such as blood transfusions help to relieve these symptoms. Medications and stem cell transplants slow MDS by helping your body make more healthy blood cells.