MDS is an updated term for what was previously known as pre-leukemia. It refers to a group of blood disorders that occur when specific types of blood cells become dysfunctional.

Myelodysplastic syndrome (MDS) used to be referred to as “pre-leukemia” or sometimes “smoldering leukemia.” MDS is a group of conditions that occur when blood-forming cells found in bone marrow become abnormal. It can cause you to have low levels of:

  • red blood cells
  • white blood cells
  • platelets

Several different types of MDS exist. They’re primarily based on the cells’ appearance when viewed under a microscope. Other factors, such as how many types of blood cells are affected, also play a role.

Symptoms of MDS can vary depending on which type (or types) of blood cells are affected. Many people with MDS have no symptoms, and their diagnosis is made with incidental findings on blood work.

If they do occur, possible MDS symptoms include:

1. Fatigue

MDS can cause low levels of red blood cells, a condition known as anemia. Red blood cells are important because they carry oxygen and nutrients throughout your body. This can result in fatigue, a well-known symptom of anemia.

Other symptoms of anemia include:

  • shortness of breath
  • lightheadedness, dizziness
  • paleness
  • cold hands and feet
  • general weakness
  • irregular heart rate
  • headache
  • chest pain

Symptoms of anemia tend to get worse over time.

2. Unexplained bruising or pinpoint spots on the skin

You may experience some skin symptoms if MDS causes thrombocytopenia, or low levels of platelets.

Platelets are the components of your blood that enable it to clot. Problems with blood clotting, such as a lack of sufficient blood clotting when needed, can cause bleeding into your skin, leading to unexplained red, brown, or purple bruises, known as purpura, or red or purple pinpoint spots, known as petechiae.

These pinpoint spots may be raised or flat on the skin. They usually aren’t itchy or painful but stay red even if you press them.

3. Bleeding easily

Low platelet levels can cause you to bleed easily, even after just a minor bump or scrape. You may also experience spontaneous nosebleeds or bleeding gums, especially after dental work.

4. Frequent infections

Frequent infections may occur if you have low levels of white blood cells called neutrophils. A low level of neutrophils is also known as neutropenia.

A low white blood cell count is known as leukopenia. White blood cells are an important part of your immune system, helping your body fight infection.

Low levels of white blood cells can make you more susceptible to infections that affect your:

  • lungs
  • throat
  • sinuses
  • skin
  • mouth
  • ear
  • gums

5. Bone pain

If MDS becomes severe, it can cause bone pain.

MDS is caused by defective bone marrow stem cells. Bone marrow is the material found inside your bones. It’s where your blood cells are made. Stem cells are a type of cell found in your bone marrow that is responsible for producing your blood cells.

In MDS, these bone marrow stem cells start producing abnormal blood cells that aren’t properly formed and die too quickly or are destroyed by your body. This leaves your body with too few functioning blood cells to carry oxygen, stop bleeding, and fight infections.

What causes the defective stem cells is not always known, although scientists think genetic mutations may be the cause. There are two classifications of MDS. Most people have primary MDS or de novo MDS. In primary MDS, the defective bone marrow stem cells have no known cause.

Secondary MDS is treatment-related. It usually occurs in people who have been treated for prior cancer. This is because chemotherapy and radiation therapy can damage the stem cells in your bone marrow.

Several factors can increase your risk of developing MDS:

  • previous treatment with chemotherapy
  • previous radiation therapy or other long-term exposure to radiation
  • long-term exposure to high levels of benzene or toluene

The vast majority of people diagnosed with MDS are in their 70s. It’s uncommon to develop the condition before age 50. Males are more likely than females to develop MDS.

If you are at higher risk of developing MDS and have some of the symptoms, make an appointment to see your doctor.

Many people with MDS have no symptoms or only minor symptoms. A doctor may recommend testing for MDS based on the results of a routine blood test.

In MDS, blood counts are usually low. But in some cases, the white blood count level or platelet counts are higher than normal.

To diagnose MDS, a doctor orders a bone marrow aspiration and a bone marrow biopsy. During these procedures, a thin, hollow needle is inserted into a hip bone to remove a sample of marrow, blood, and bone.

A microscopic analysis of the chromosomes, known as a cytogenetic study, will reveal the presence of any abnormal bone marrow cells.

An allogeneic blood and marrow transplantation (BMT), also known as a bone marrow transplant or stem cell transplant, is the only potential cure for MDS.

BMT involves using high dose chemotherapy drugs followed by infusion of donor blood and bone marrow. It can be a dangerous procedure, especially for older adults. It isn’t appropriate for everyone.

When BMT isn’t an option, other treatments can reduce symptoms and delay the development of acute myeloid leukemia (AML). Some of these are:

  • transfusion therapy to increase the number of red blood cells and platelets
  • antibiotics to prevent infection
  • chelation therapy to remove excess iron from the blood
  • growth factor therapy to increase the number of red blood cells
  • chemotherapy to kill or stop the growth of fast-growing cells
  • epigenetic therapy to stimulate tumor-suppression genes
  • biologic therapy to improve red blood cell production in people missing the long arm of chromosome 5, otherwise known as 5q minus syndrome

Symptoms of MDS and early AML are similar. About one-third of people with MDS eventually develop AML, but early treatment for MDS can help delay the onset of AML. Cancer is easier to treat in the earliest stages, so it’s best to get a diagnosis as quickly as possible.

Is pre-leukemia a cancer?

Myelodysplastic syndrome is considered a cancer.

It’s a set of conditions that occur when cells in the bone marrow that produce new blood cells are dysfunctional. When these damaged blood cells form new blood cells, they develop defects and either die earlier than normal cells or the body destroys the abnormal cells, leaving the patient with low blood counts.

In about one-third of patients diagnosed with MDS, acute myeloid leukemia develops due to the progression of rapidly growing cancer of the bone marrow. Because this condition does not occur in most MDS patients, the terms “pre-leukemia” and “smoldering leukemia” are no longer used.

How long can you live with myelodysplastic syndrome?

The life expectancy of a person with myelodysplastic syndrome can vary widely according to their risk level on one of the two scoring systems used to predict the outlook for people with these cancers. The median survival rating can vary from less than one year to almost 12 years, depending on a person’s score. It’s also important to note these statistics improve over time as treatments improve.

What are the early warning signs of leukemia?

Leukemia can cause fatigue, frequent infections, frequent bleeding and bruising, and anemia, among other symptoms. People with myelodysplastic syndrome, which in some cases can develop into acute myeloid leukemia, may not experience any symptoms. But they may have a low blood cell count or a high white blood cell or platelet count.

Is there such a thing as borderline leukemia?

A person receives a diagnosis of leukemia when the bone marrow shows greater than or equal to 20% blasts (immature blood cells). If the sample on bone marrow biopsy is close to 20%, it may be considered borderline leukemia.

Myelodysplastic syndrome (MDS) occurs when a person’s bone marrow produces cells that are dysfunctional. In one-third of people with MDS, acute myeloid leukemia develops.