Myelodysplastic Syndromes - MDS: Diagnosis

Approved by the Cancer.Net Editorial Board, 12/2017

ON THIS PAGE: You will find a list of common tests, procedures, and scans that doctors use to find the cause of a medical problem. Use the menu to see other pages.

Doctors use many tests to find, or diagnose, cancer. They also do tests to learn the extent of the disease. Doctors may also do tests to learn which treatments could work best.

For most types of cancer, a biopsy is the only sure way for the doctor to know if an area of the body has cancer. In a biopsy, the doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis.

This list describes options for diagnosing this type of cancer. Not all tests listed below will be used for every person. Your doctor may consider these factors when choosing a diagnostic test:

  • The type of cancer suspected

  • Your signs and symptoms

  • Your age and general health

  • The results of earlier medical tests

In addition to a physical examination, the following tests may be used to diagnose MDS:

  • Blood tests. A complete blood count, or CBC, measures the numbers of red blood cells, white blood cells, and platelets. Blood tests may also be done to rule out other conditions that can cause symptoms similar to MDS, such as low levels of vitamin B12, folate, copper, and thyroid problems.

  • Peripheral (circulating) blood smears. A drop of blood is placed on a slide, smeared into a thin film, and placed under a microscope for examination. The percentages of the different types of cells are counted. Also, the appearance of cells under the microscope, called cell morphology, is looked at to find out if or how the cells are different from healthy cells.

  • Bone marrow aspiration and biopsy. These 2 procedures are similar and often done at the same time to examine the bone marrow. Bone marrow has both a solid and liquid part. A bone marrow aspiration removes a sample of the fluid with a needle. A bone marrow biopsy is the removal of a small amount of solid tissue using a needle.

    A pathologist then analyzes the sample(s) to determine the percentage of red blood cells, white blood cells, platelets, and blasts. A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease. A common site for the bone marrow aspiration and biopsy is the pelvic bone, which is located in the lower back by the hip. The skin in that area is numbed with medication beforehand. Other types of anesthesia, which is medication to block the awareness of pain, may also be used. The appearance of the bone marrow tissue, along with blood cell counts and chromosomal analysis (see below), is needed to confirm a diagnosis of MDS.

  • Molecular testing. Your doctor may recommend running laboratory tests on a bone marrow sample to identify specific genes, proteins, and other factors unique to MDS. Results of these tests can help determine your treatment options, find out how treatment is working, and learn about the likelihood of recovery after a stem cell/bone marrow transplant.

  • Cytogenetic (chromosomal) analysis. Looking at the chromosomes of the cells in the blood and bone marrow shows specific abnormalities that help doctors tell the difference between MDS and other blood disorders. About 50% of people with MDS have 1 or more chromosomal abnormalities, regardless of the subtype. Primary MDS often has 1 chromosomal abnormality. Secondary MDS often has many or complex chromosomal changes. The most common abnormalities affect chromosomes 5, 7, 8, 11, 12, and 20.

  • Immunophenotyping. Immunophenotyping is the examination of antigens, a specific type of protein, on the surface of the MDS cells. Immunophenotyping can help identify the type of MDS.

After diagnostic tests are done, your doctor will review all of the results with you. If the diagnosis is MDS, these results also help the doctor describe the disease.

The next section in this guide is Subtypes and Classification. It explains the system doctors use to describe MDS. Use the menu to choose a different section to read in this guide.