Myelodysplastic syndromes (MDS) are a group of related conditions that interfere with your body’s ability to make healthy blood cells. MDS are a type of blood cancer.

In the early stages, there may be no symptoms. But, in time, a person may start to experience fatigue due to anemia, easy bruising and bleeding, and frequent infections.

Often, there is no clear cause, but exposure to certain chemicals — for instance, during chemotherapy or when working with solvents — may increase the risk.

Treatment is with medications or stem cell therapy, and the outlook depends on the type of MDS.

Inside most of your larger bones is a fatty, spongy tissue called bone marrow. It’s here that “blank” stem cells transform into immature blood cells (called blasts).

They’re destined to become either a mature:

This process is called hematopoiesis.

If you have MDS, your bone marrow can still produce stem cells that become immature blood cells. However, many of these cells don’t develop into healthy, mature blood cells.

Some blood cells die before they leave your bone marrow. Others that do get into your bloodstream may not function normally.

The result is low numbers of one or more types of blood cells (cytopenia) that are abnormally shaped (dysplastic).

The World Health Organization (WHO)’s Classification of Myelodysplastic Syndromes takes into account:

  • kind of blood cells affected
  • percentage of immature cells (blasts)
  • number of dysplastic (abnormally shaped) cells
  • presence of ring sideroblasts (an RBC that has extra iron collected in a ring in its center)
  • changes in chromosomes seen in bone marrow cells

The types include:

  • MDS with single linage dysplasia (MDS-SLD)
  • MDS with ring sideroblasts (MDS-RS)
  • MDS with multilinear dysplasia (MDS-MLD)
  • MDS, unclassified (MDS-U)
  • MDS associated with isolated del(5q)
  • MDS with excess blasts-1 (MDS-EB1)
  • MDS with excess blasts-2 (MDS-EB2)

The percentage of blasts in bone marrow and blood differentiates MDS EB1 and EB2.

The symptoms of MDS depend on the disease stage and the blood cell types that are affected.

MDS is a progressive disease. In the early stages, there are usually no symptoms. In fact, MDS are often discovered accidentally when low blood cell counts are found when blood tests are done for another reason.

In later stages, low blood cell levels cause different symptoms depending on the type of cell involved. You may have several types of symptoms if more than one cell type is affected.

Red blood cells

Red blood cells (RBCs) transport oxygen throughout your body. A low RBC count is called anemia. It’s the most common cause of MDS symptoms, which may include:

White blood cells

White blood cells (WBCs) help your body fight infections. Low WBC counts (neutropenia) are associated with symptoms of bacterial infections that vary depending on where the infection occurs. Often, you’ll have a fever.

Common sites of infection include:

  • The lungs: Pneumonia may occur, which features a cough and shortness of breath.
  • The urinary tract (UTI): UTIs can cause painful urination and blood in your urine.
  • The sinuses: A sinus infection may involve a stuffy nose and head pain above the eyes.
  • The skin: An infection in the deeper layers of the skin, known as cellulitis, can cause warm areas that may drain pus.


Platelets help your body form clots and bleeding.

Symptoms of low platelet counts, known as thrombocytopenia, may include:

When blood cell counts get very low, complications can develop. They’re different for each blood cell type. Some examples are:

  • Severe anemia: This can lead to severe fatigue, trouble concentrating, confusion, and difficulty standing due to dizziness.
  • Severe neutropenia: This can lead to recurrent infections and a risk of sepsis.
  • Severe thrombocytopenia: This can result in nosebleeds that won’t stop, bleeding gums, and internal bleeding, such as from an ulcer, that’s difficult to stop.

Over time, MDS can transform into another blood cancer called acute myeloid leukemia (AML).

According to the American Cancer Society, about 1 in 3 people with MDS develop AML.

Often, the cause of MDS isn’t known, but some factors may increase the risk, such as:

Having been exposed to certain chemicals and substances for a long time may also increase your risk. Some of these substances are:

  • tobacco smoke
  • pesticides
  • fertilizers
  • solvents such as benzene
  • heavy metals such as mercury and lead

Three types of treatment are used for different reasons.

Supportive care

This is used to make you feel better, improve your symptoms, and help avoid complications from MDS.

It may include:

  • transfusions to boost low RBC or platelet counts
  • antibiotics to treat or lower the risk of infections due to low WBC counts
  • growth factors to boost the production of RBCs in the bone marrow

Treatment to slow MDS progression

Treatment for MDS will depend on the severity and progression of the condition.

Low-intensity chemotherapy

A doctor prescribes weaker drugs at lower doses to reduce the risk of severe side effects. Examples include azacytidine and decitabine.

Low-intensity chemotherapy is typically an option for older adults and those with low risk MDS.

High-intensity chemotherapy

These are strong drugs given at high doses, which means they may cause severe side effects. A doctor may prescribe these drugs to treat MDS that’s transformed into AML or in preparation for a stem cell transplant.

  • cytarabine
  • daunorubicin
  • idarubicin


Also called biologic therapy, immunotherapy helps your body’s defense systems fight disease. There are a number of different types.

Treatment for long-term remission

A stem cell transplant is the only available option that can cause long-term remission for MDS.

A person will first need high dose chemotherapy to destroy the stem cells in their bone marrow. A transplant then replaces these with healthy donor stem cells.

What are the current treatment options for MDS?

Several tests are used to diagnose and determine the subtype of MDS.

  • Complete blood count (CBC): A CBC shows the number of each type of blood cell. One or more types will be low if you have MDS.
  • Peripheral blood smear: For a peripheral blood smear, a technician will place a drop of your blood on a slide to examine it under a microscope. It’s checked to determine the percentage of each type of blood cell and if any cells are dysplastic.
  • Bone marrow aspiration and biopsy: A bone marrow aspiration and biopsy involves inserting a hollow needle into the center of your hip or breastbone to remove samples from the bone marrow. It can confirm or rule out MDS.
  • Cytogenetic analysis: These tests use blood or bone marrow samples to look for genetic changes.

Doctors use a complex scoring system to estimate an individual’s outlook with MDS. This will depend on the type of MDS they have.

The system classifies the person’s condition into a lower-risk or higher-risk group based on:

  • MDS subtype
  • number of blood cell types with low counts and their severity
  • percentage of blasts in the bone marrow
  • presence of chromosome changes

The groups indicate how MDS might progress in that person if they don’t have treatment. They don’t tell you how it might respond to treatment.

Lower-risk MDS tends to progress slowly. It may be years before it causes severe symptoms, so it’s not treated aggressively.

Higher-risk MDS tends to progress rapidly, and severe symptoms appear sooner. It’s also more likely to transform into AML, so it needs more aggressive treatment.

A doctor will look at your risk group as well as a variety of other factors to determine the best treatment options for you.

What is the life expectancy of someone with myelodysplastic syndromes?

This will depend on the type of MDS and how a person’s body responds to treatment. Some types develop slowly over many years, while others progress more rapidly.

Is myelodysplasia a form of leukemia?

MDS is a group of conditions that are a type of blood cancer. Around one third of people with MDS will develop acute myeloid leukemia, or AML.

Can myelodysplasia be cured?

A stem cell transplant is usually considered the only potential cure for MDS. It can come with a risk of serious complications, so speak with your doctor about whether this treatment may be an option for you.

If a transplant is not an option, there are other treatments that can prolong a person’s life and help improve their comfort and quality of life.

What is the main cause of MDS?

It’s not clear what the main cause is, but genetic features and exposure to certain chemicals may increase the risk. It does not usually run in families.

MDS are a type of blood cancer in which your bone marrow fails to produce adequate numbers of functioning blood cells. There are several different subtypes, and the condition may progress rapidly or slowly.

Chemotherapy can help slow the progression of MDS, but a stem cell transplant can achieve longer-term remission.

Other treatments are available for supportive care when symptoms such as anemia, bleeding, and recurrent infections occur.