Diagnosis

Doctors use many tests to diagnose cancer and determine if it has metastasized (spread). Some tests may also determine which treatments may be the most effective. For most types of cancer, a biopsy is the only way to make a definitive diagnosis of cancer. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis. Imaging tests may be used to find out whether the cancer has metastasized. Your doctor may consider these factors when choosing a diagnostic test:

• Age and medical condition
• The type of cancer suspected
• Severity of symptoms
• Previous test results

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

Blood and urine tests. Myeloma cells secrete an antibody known as the M protein (monoclonal immunoglobulin). Levels of the M protein in a patient's blood and urine are used to determine the extent of the disease and to monitor the effectiveness of treatment. Blood tests are also used to measure kidney function, calcium levels, and blood counts (for possible anemia).

Bone marrow biopsy. In a bone marrow biopsy, a needle is inserted through the skin into the back of the pelvic (hip) bone to remove a small amount of tissue. The tissue is then examined under a microscope by a pathologist (a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease). To minimize pain during the procedure, a local anesthesia is given to numb the area or the patient may be sedated.

Fat pad aspirate. If amyloidosis (a disorder where certain proteins accumulate in body tissues and organs) is a consideration, it may be necessary to take a sample of the abdominal fat pad (the collection of fat around a person's abdomen) for examination under a microscope, called a biopsy.

Imaging

X-ray. An x-ray is a picture of the inside of the body. X-rays are typically the first step in evaluating myeloma in the bones.

Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. An MRI can show replacement of normal bone marrow by myeloma cells or plasmacytoma (a plasma cell tumor growing in bone or soft tissue), especially in the skull, spine, and pelvis. The detailed images may also show compression fractures of the spine or a tumor pressing on nerve roots. A contrast medium (a special dye) may be injected into a patient’s vein to create a clearer picture.

Computed tomography (CT or CAT) scan. A CT scan creates a detailed, cross-sectional view that shows any abnormalities or tumors in soft tissues. A computer then combines these images into a three-dimensional picture of the inside of the body. Sometimes, a contrast medium is injected into a patient’s vein to provide better detail, but it is used cautiously in patients with multiple myeloma because of a risk of kidney failure

Positron emission tomography (PET) scan. A PET scan is a way to create pictures of organs and tissues inside the body. A small amount of a radioactive substance is injected into a patient’s body and absorbed by the organs or tissues being studied. This substance gives off energy that is detected by a scanner, which produces the images.

Bone scan. A bone scan uses a radioactive tracer to look at the inside of the bones. The tracer is injected into a patient’s vein. It collects in areas of the bone and is detected by a special camera. Healthy bone appears gray to the camera, and areas of injury, such as those caused by cancer, appear dark.

To learn about the terms used in this section, read the Cancer.Net Feature: Cancer Terms to Know: Newly Diagnosed.

To learn more about what to expect during common diagnostic tests, read Cancer.Net: Tests and Procedures.