If symptoms suggest that a person may have multiple myeloma, laboratory tests on blood and/or urine, x-rays of the bones, and a bone marrow biopsy are usually done.

Laboratory tests

Blood counts

The complete blood count (CBC) is a test that measures the levels of red cells, white cells, and platelets in the blood. If myeloma cells occupy too much of the bone marrow, these levels will be low.

Quantitative immunoglobulins

This test measures the blood levels of the different antibodies. There are several different types of antibodies in the blood: IgA, IgE, IgG, and IgM. The levels of these immunoglobulins are measured to see if any are abnormally high or low. In multiple myeloma, the level of one type may be high while the others are low.

Electrophoresis

The immunoglobulin produced by the myeloma cells is abnormal because it is monoclonal Serum protein electrophoresis (SPEP) is a test to measure the total amount of immunoglobulin in the blood and find any abnormal immunoglobulin. Then, another test, such as immunofixation or immunoelectrophoresis, is used to determine the exact type of antibody that is abnormal (IgG or some other type). Finding a monoclonal immunoglobulin in the blood may be the first step in making the diagnosis of multiple myeloma. This abnormal protein is known by several different names, including monoclonal immunoglobulin, M protein, M spike, and paraprotein.

Immunoglobulins are made up of protein chains: 2 long (heavy) chains and 2 shorter (light) chains. Sometimes the kidneys excrete pieces of the M protein into the urine. The protein in the urine is the part of the immunoglobulin called the light chain. This urine protein is also known as Bence-Jones protein. The test used for finding a monoclonal immunoglobulin in the urine is called urine protein electrophoresis (UPEP) and urine immunofixation.

Free light chains

This test measures the amount of light chains in the blood. This can be helpful in the rare cases of myeloma in which no M protein is found by SPEP. (The SPEP measures the levels of intact [whole] immunoglobulins.)

Beta-2 microglobulin

This is another protein produced by the malignant cells. Although this protein itself doesn’t cause any problems, it can be a useful indicator of a patient’s prognosis (outlook). High levels indicate more advanced disease and may indicate a worse prognosis.

Blood chemistry tests

Levels of blood urea nitrogen (BUN) and creatinine, albumin, calcium, and other electrolytes will be checked

• BUN and creatinine levels show how well your kidneys are working. Increased levels mean that kidney function is impaired. This is common in people with myeloma.

• Albumin is a protein found in the blood. Low levels can be a sign of more advanced myeloma.

• Calcium levels may be higher in people with advanced myeloma. High calcium levels can cause severe symptoms of fatigue,weakness, and confusion..

• Levels of electrolytes such as sodium and potassium may be affected as well.

Bone marrow biopsy

People with multiple myeloma have too many plasma cells in their bone marrow. The procedure to check the bone marrow is called a bone marrow biopsy and aspiration. It can be either done at the doctor's office or at the hospital.

In this procedure, the back of the pelvic bone is numbed with local anesthetic. Then, to do the bone marrow aspiration, a needle is inserted into the bone, and a syringe is used to remove a small amount of liquid bone marrow. For a bone marrow biopsy, a needle is used to remove a tiny sliver of bone and marrow, about 1/16-inch across and 1-inch long. There is some soreness in the biopsy area when the numbing medicine wears off. Most patients can go home immediately after the procedure. A doctor will use a microscope to look at the bone marrow tissue to determine if there are myeloma cells in the bone marrow and, if so, how many. The aspirate may be sent for chromosome tests.

Other biopsy tests

If an area looks abnormal on an x-ray, a biopsy may be needed to confirm that it is a plasmacytoma.

Fine needle aspiration biopsy:

Fine needle aspiration (FNA) uses a very thin needle and an ordinary syringe to withdraw a small amount of tissue from a tumor or lymph node. The doctor can aim the needle while feeling an enlarged node near the surface of the body. If the tumor is deep inside the body, the needle can be guided while it is viewed on a computed tomography (CT) scan (see discussion of imaging tests later in this section). The main advantage of FNA is that it does not require surgery. The disadvantage is that in some cases the thin needle cannot remove enough tissue for a definite diagnosis. FNA can be useful in diagnosing cancers that have spread to nodes from other organs.

Core needle biopsy

This test is similar to FNA, but a larger needle is used and a larger tissue sample is removed.

Imaging studies

Bone x-rays

Bone destruction caused by the myeloma cells can be detected with x-rays. Often doctors will do a series of x-rays that includes most of the bones. This is called a bone survey.

Computed tomography

The computed tomography (CT) scan (also known as a CAT scan) is an x-ray procedure that produces detailed cross-sectional images of your body. Instead of taking one picture, like a conventional x-ray, a CT scanner takes many pictures of the part of your body being studied as it rotates around you. A computer then combines these pictures into an image of a slice of your body. Sometimes, this test can help tell if your bones have been damaged by myeloma.

You may be asked to drink 1 to 2 pints of a solution of contrast material before the scan. This helps outline the intestine so that it is not mistaken for tumors. You may also receive an intravenous (IV; in the vein) line through which a different contrast dye is injected. This helps better outline structures in your body. The injection can cause a feeling of warmth throughout the body (flushing). Some people are allergic to the IV contrast and get hives. Rarely, more serious reactions like trouble breathing and low blood pressure can occur. Medicine can be given to prevent and treat allergic reactions. Be sure to tell the doctor if you have ever had a reaction to any contrast material used for x-rays. If IV contrast is being used, it is important you tell the radiology people that you have myeloma. Some of these contrast agents can damage the kidneys of people with myeloma.

CT scans are more tedious than regular x-rays because they take longer and you usually need to lie still on a table a while they are being done. But just like other computerized devices, they are getting faster and your stay might be pleasantly short. Some modern scanners can complete the study in seconds. Also, you might feel a bit confined by lying within the equipment while the pictures are being taken.

CT scans can also be used to guide a biopsy needle precisely into a suspected tumor. For this procedure, called a CT-guided needle biopsy, the patient remains on the CT scanning table while a radiologist advances a biopsy needle toward the location of the tumor. CT scans are repeated until the doctors are confident that the needle is within the mass. A fine needle biopsy sample (tiny fragment of tissue) or a core needle biopsy sample (a thin cylinder of tissue about ½-inch long and less than 1/8 inch in diameter) is removed and examined under a microscope.

Magnetic resonance imaging

MRI scans use radio waves and strong magnets instead of x-rays. The energy from the radio waves is absorbed and then released in a pattern formed by the type of tissue and by certain diseases. A computer translates the pattern of radio waves given off by the tissues into a very detailed image of parts of the body. Not only does this produce cross-sectional slices of the body like a CT scanner, it can also produce slices that are parallel with the length of your body. A dye (contrast material) might be injected just as with CT scans but is used less often.

MRI scans are very helpful in looking at bones, the brain, and the spinal cord. They may be able to find plasmacytomas that cannot be seen on regular x-rays. MRI scans are a little more uncomfortable than CT scans. First, they take longer -- often up to an hour. Also, you have to be placed inside tunnel-like equipment, which is confining and can upset people with claustrophobia. The machine also makes a thumping noise that you may find disturbing. Some places provide headphones with music to block this out.

Positron emission tomography

In this test, which is also called a PET scan, radioactive glucose (sugar) is injected into the patient's vein to look for cancer cells. Because cancers use glucose (sugar) at a higher rate than normal tissues, the radioactivity will tend to concentrate in the cancer. A scanner is used to spot radioactive deposits. When a patient appears to have a solitary plasmacytoma, a PET scan may be used to look for other plasmacytomas.

Interpreting test results

Results of any single test are not enough to make a diagnosis of multiple myeloma. Diagnosis is based on a combination of factors, including the patient's description of symptoms, the doctor's physical examination of the patient, and the results of blood tests and x-rays. The diagnosis of multiple myeloma requires either:

• a plasma cell tumor (proven by biopsy)

OR

• at least 10% of the cells in the bone marrow be plasma cells.

And also one of the following:

• M protein over a certain level in the blood (3g/dL)

OR

• M protein in the urine over a certain level (1g/dL)

OR

• holes in bones due to tumor growth are found on imaging studies.

Smoldering myeloma

This is a term used to mean early myeloma that is not causing any symptoms or problems. People with smoldering myeloma have normal blood counts, normal calcium levels, normal kidney function, and no bone or organ damage. Smoldering myeloma does not need to be treated right away.

Last Medical Review: 02/13/2009
Last Revised: 05/12/2009