How is myelodysplastic syndrome found?

Follow-up exams and blood tests may help find some cases of MDS in people who were treated with certain chemotherapy drugs in the past. But at this time, no special tests are used to look for myelodysplastic syndromes (MDS) in people without symptoms.

Signs and symptoms of MDS

MDS can cause many signs and symptoms such as weight loss, fever, and loss of appetite. Of course, these problems are most often caused by something other than cancer.

Shortages of one or more types of blood cells cause many of the symptoms of MDS.

• A shortage of red blood cells can cause tiredness, shortness of breath, and pale skin.
• A shortage of normal white blood cells can lead to infections and high fevers.
• A shortage of platelets can cause easy bruising and bleeding.

Tests used to find and classify MDS

If there is any reason to suspect MDS, the doctor will look at cells from your blood and bone marrow to find out if the disease is really there.

Blood cell counts and blood cell exams

The complete blood count (CBC) is a test that measures the different cells in the blood, like red blood cells, white blood cells, and platelets. Patients with MDS will often have changes in the numbers of different blood cell types. Under the microscope the cells may also look different in shape and size. Blood tests can suggest MDS, but the doctor will need to look at a sample of bone marrow cells to be sure.

Bone marrow tests

Bone marrow samples are taken by a bone marrow aspiration and biopsy. These 2 tests are most often done at the same time. For these tests, you lie on a table (either on your side or on your belly). The sample is taken from the back of the hip (pelvic) bone. After cleaning the area, the skin is numbed and then a needle is used to suck out a small amount of liquid bone marrow. Even with the numbing medicine, most patients have some brief pain when the marrow is removed.

A bone marrow biopsy is usually done just after the aspiration. A small piece of bone and marrow is removed with a different needle that is twisted as it is pushed down into the bone. The biopsy may also cause some brief pain. Once the biopsy is done, pressure will be applied to help prevent bleeding.

A doctor with special training (a pathologist) will look at the sample of cells under a microscope to see if cancer is present and if so, what kind it is. The percentage of marrow cells that are blasts is very important. Blasts are very early cells that are made by bone marrow stem cells. Over time, blasts should change (mature) into normal blood cells. In MDS, the blasts do not mature, so there may be too many blasts and not enough mature cells. A patient with less than 20% blasts in the bone marrow has MDS. A patient who has more than 20% blasts in the bone marrow is considered to have acute leukemia.

Other tests

There are a number of other ways to study the cells from blood or bone marrow. These tests use chemicals or other methods to help the doctor pinpoint the exact type of cells that are present. You can ask your doctor to explain what types of tests were done and what they showed.