Tests provide much of the information that will help you understand your cancer. This page describes the major tests involved in the diagnosis and treatment of metastatic breast cancer. Remember that not all tests work for every diagnosis.

You deserve the best information about your tests, so if you feel unsure or don’t understand your doctor’s approach, ask questions.

The most typical scans include:

• Bone Scans
• Chest X-Ray
• CT Scan (Computerized Tomography; CAT Scan)
• MRI (Magnetic Resonance Imaging)
• PET Scan (Positron-Emission Tomography)
• Blood Tests

Bone Scans

As their name implies, these scans test if cancer has spread to the bones. In a quarter of metastatic-breast-cancer cases, metastases occur in the bones first. The test looks at the bones for “hot spots” that may reveal cancer. These tests provide an opening for understanding your cancer, helping doctors determine which further tests to perform. To conduct a bone scan, your doctor injects dye and then waits a few hours for it to move through the bloodstream, becoming visible in the scan.

Chest X-Ray

This test may reveal if breast cancer has spread to the lungs. Metastases in the lungs rarely cause pain, a symptom doctors commonly look for in other parts of the body, but these metastases can cause shortness of breath or a cough that won’t go away.

CT Scan (Computerized Tomography; CAT Scan)

This scan provides a more-detailed x-ray of the body, usually in order to look for metastases in the brain, lungs or liver. Before the scan, you will either ingest a contrast dye and/or have it injected into a vein. The dye can highlight specific areas of the body—a possible sign of cancer growth. Then the exam table is moved through the scanner and a computer creates multi-dimensional images for the doctor to examine.

MRI (Magnetic Resonance Imaging)

This test looks for cancer throughout the body or a particular area in question such as the brain. Patients lie on a table which goes inside the MRI machine which takes three-dimensional pictures of the body using radio waves, a magnet and a computer. You may be given a contrast die before or during the scan. Doctors use these pictures to look for cancer. Please note that some people feel claustrophobic inside the machine. This test can take 20 minutes or more. If this might trouble you, talk to your healthcare team about ways to make the test less uncomfortable.

PET Scan (Positron-Emission Tomography)

This scan works by monitoring the use of glucose in specific parts of the body. Cancer cells use more glucose, a source of energy, than normal cells do. Before the scan, you will have some radioactive glucose called a “tracer” injected into a vein. A computer then takes images and looks for the areas using the most glucose. The PET scan can sometimes find cancer that other tests miss.

Blood Tests

Different blood tests may be used to detect breast cancer:

• The CA 27.29 blood test measures the level of a protein called the CA 27.29 antigen, often found in the blood of women with breast cancer. In theory, the level rises with more breast cancer. However, this test does not accurately check for metastases. It can, in some patients, help determine if cancer is growing in the body, and thus if treatments are working.
• Similar tests include the CA-15-3 and CEA.
• Another blood test measures circulating tumor cells (CTCs). These appear frequently in people with metastatic cancer, but not healthy individuals or those with nonmalignant diseases. Evidence shows that CTC tests can help doctors measure and predict cancer progression and test how well therapies work.