Making a diagnosis of myeloma depends on finding abnormal plasma cells or their products somewhere in the body. Plasma cells are cells of the immune system that make antibodies when they are functioning normally. In myeloma, these cells begin to grow and divide abnormally, and they make abnormal amounts of antibody-like proteins.
The growth of these plasma cells in the bone marrow can reduce the normal function of the bone marrow. It can also result in thinned, weakened bones that are apt to break. Accumulation of the abnormal antibody-like protein in the blood can cause problems with blood flow to the kidney and other parts of the body. Usually, symptoms related to these changes bring a patient to the doctor or raise the suspicion of myeloma.
The diagnosis and prognosis of multiple myeloma include the following:
Diagnosis begins with a visit to the doctor. Sometimes, multiple myeloma is noted when blood tests are ordered for an unrelated reason. A biopsy will be necessary to confirm the presence of myeloma cells.
The doctor will ask about your symptoms and medical history. He or she will inquire about how your symptoms have progressed. The doctor may also ask about anything that may increase your risk of multiple myeloma, such as exposure to radiation or toxic chemicals.
The doctor will perform a complete physical exam. This will focus on uncovering evidence of bone damage,
anemia, or impaired circulation, each of which might be the result of myeloma.
To help with the diagnosis, your doctor may do any of the following:
Urine tests—to check for high levels of antibody proteins
Blood tests—to check for problems associated with multiple myeloma:
Low levels of white or red blood cells
Increased levels of calcium, which can result from the destruction of bone by myeloma cells
High levels of antibody proteins and chemicals in the body related to decreased kidney function
Bone marrow aspiration or
biopsy—A sample of liquid bone marrow is removed and tested for the presence of myeloma cells. This test can also indicate how well the bone marrow is functioning. The sample is obtained by inserting a needle into the pelvic bone, which may be done in the hospital or outpatient setting.
Cytology is the study of cells. The cytology of cancer cells differs significantly from normal cells. Doctors use the unique cellular features seen on biopsy samples to determine the diagnosis and assess the prognosis of a cancer.
To diagnose myeloma, the doctor will look for abnormal plasma cells, which are the cells responsible for myeloma. A plasma cell labeling index, which measures the percentage of dividing plasma cells, is available in some labs. This test gives an idea of how fast the cancer cells are growing. A higher labeling index is associated with a worse prognosis because it means that there are more, faster reproducing plasma cells present than there should be.
Staging is the process by which doctors determine the prognosis of a cancer that has already been diagnosed. Staging is essential for making treatment decisions (eg, surgery vs. chemotherapy). Several features of the cancer are used to arrive at a staging classification, the most common being the size of the original tumor, extent of local invasion, and spread to distant sites (metastasis). Low staging classifications (0-1) imply a favorable prognosis, whereas high staging classifications (4-5) imply an unfavorable prognosis.
The Durie-Salmon staging system is used to stage multiple myeloma. The amount of tumor in the body is estimated based on the following factors:
Blood or urine level of abnormal antibody-like proteins—These are produced by myeloma cells.
Blood level of calcium—High levels are associated with bone damage caused by myeloma cells growing in the bone marrow and destroying the surrounding bone as their mass expands.
Bone damage evident on x-ray—This is also a result of destruction of bone caused by growing myeloma cells. This damage has a characteristic appearance on x-ray, and sometimes an x-ray alone will give good evidence of myeloma.
Blood hemoglobin level—Hemoglobin is the red pigment in red blood cells that carries oxygen to the cells. Low levels may indicate decreased production of red cells due to myeloma cells occupying the bone marrow.
Blood level of beta-2-microglobulin—This is another protein produced by myeloma cells. Increased levels of this protein suggest a large amount of myeloma in the body.
In general, the more myeloma cells and/or their products present in the body, the higher the stage and the worse the prognosis. Patients with higher stage disease also tend to have more symptoms from their disease. Based on the Durie-Salmon system, staging of multiple myeloma is as follows:
A relatively small number of myeloma cells are present. (This can be measured by plasma cell index.)
Hemoglobin levels are slightly low.
Bone x-rays show no damage or only one area of damage.
Calcium levels are normal indicating that there is not much bone damage.
There is a small amount of abnormal antibody-like protein in the blood or urine.
A moderate amount of myeloma cells are present.
Other factors fall in a range between Stage I and Stage III.
A large amount of myeloma cells are present.
Hemoglobin levels are very low, indicating that the normal bone marrow cells are being crowded out.
Calcium levels are high, indicating that there is a large amount of bone destruction.
X-rays show more than three areas of bone destruction.
A large amount of abnormal antibody-like protein is in the blood or urine.
Prognosis is a forecast of the probable course and/or outcome of a disease or condition. Prognosis is most often expressed as the percentage of patients who are expected to survive over five or ten years. Cancer prognosis is a notoriously inexact process. This is because the predictions are based on the experience of large groups of patients suffering from cancers at various stages. Using this information to predict the future of an individual patient is always imperfect and often flawed, but it is the only method available. Prognoses provided in this monograph and elsewhere should always be interpreted with this limitation in mind. They may or may not reflect your unique situation.
The five-year survival rates for multiple myeloma based on stage are as follows:
Please be aware that this information is provided to supplement the care
provided by your physician. It is neither intended nor implied to be a
substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER
IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the
advice of your physician or other qualified health provider prior to
starting any new treatment or with any questions you may have regarding a