Looking for Breast Cancer Spread
Once breast cancer is diagnosed, one or more of the following tests may be done. Which of these tests (if any) is done depends on how likely it is that the cancer has spread, the size of the tumor, the presence of lymph node spread, and any symptoms you are having. These tests aren’t often done for early breast cancer.
This test may be done to see if the breast cancer has spread to the lungs.
A bone scan can help show if a cancer has metastasized (spread) to the bones. It can be more useful than standard x-rays because it can show all of the bones in the body at the same time and can find small areas of cancer spread not seen on plain x-rays.
For this test, a small amount of low-level radioactive material is injected into a vein (intravenously or IV). The substance settles in areas of bone changes throughout the entire skeleton over the course of a couple of hours. You then lie on a table for about 30 minutes while a special camera detects the radioactivity and creates a picture of your skeleton.
Bone changes show up as "hot spots" on your skeleton. They attract the radioactivity. These areas may suggest metastatic cancer, but arthritis or other bone diseases can also cause the same pattern. To distinguish between these conditions, your cancer care team may use other imaging tests such as simple x-rays or CT or MRI scans to get a better look at the areas that light up, or they may even take biopsy samples of the bone.
Computed tomography (CT) scan
The CT scan is an x-ray test that produces detailed cross-sectional images of your body. Instead of taking a single picture, like a regular x-ray, a CT scanner takes many pictures as it rotates around you while you lie on a table. A computer then combines these pictures into images of slices of the part of your body being studied. In people with breast cancer, this test is most often used to look at the chest and/or abdomen to see if the cancer has spread to other organs, such as the lungs or liver.
A CT scanner has been described as a large donut, with a narrow table in the middle opening. You will need to lie still on the table while the scan is being done. CT scans take longer than regular x-rays, and you might feel a bit confined by the ring while the pictures are being taken.
Before the test, you may be asked to drink 1 to 2 pints of a liquid called oral contrast. This helps outline the intestine so that certain areas are not mistaken for tumors. You may also receive an IV (intravenous) line through which a different kind of contrast dye (IV contrast) is injected to better outline structures in your body.
The injection might cause some flushing (a feeling of warmth, especially in the face). Some people are allergic and get hives. Rarely, more serious reactions can occur like trouble breathing or low blood pressure. Be sure to tell the doctor if you have ever had a reaction to any contrast material used for x-rays.
CT guided needle biopsy: If an abnormal area is seen on a CT scan, it may need to be biopsied to see if it is cancer. The biopsy can be done using the CT scans to precisely guide a biopsy needle into the area. For this procedure, you remain on the CT scanning table while a radiologist advances a biopsy needle through the skin and toward the location of the mass (abnormal area). CT scans are repeated until the doctors are sure 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 then removed and sent to be looked at under a microscope.
Magnetic resonance imaging (MRI) scan
Using MRI scans to look at the breast was discussed earlier in the section “How is breast cancer in men diagnosed.”
MRI scans are also used to look for cancer that has spread to various parts of the body, just like CT scans. MRI scans are particularly helpful in looking at the brain and spinal cord.
There are some differences between using this test to look at the breast and other areas of the body. Firstly, you will lie face up in the machine. Second, the contrast material called gadolinium is not always needed to look at other areas of the body. Also, you may have the option of having the scan in a less confining machine known as an open MRI machine. The images from an open machine are not always as good, though, so this is not always an option.
The use of this test to look at the breast was discussed earlier in the section “How is breast cancer diagnosed?” But ultrasound can also be used to look for cancer that has spread to some other parts of the body.
Abdominal ultrasound can be used to look for tumors in your liver or other abdominal organs. When you have an abdominal ultrasound exam, you simply lie on a table and a technician moves the transducer over the skin overlying the part of your body being examined. Usually, the skin is first lubricated with gel.
Positron emission tomography (PET) scan
A PET scan is useful when your doctor thinks the cancer may have spread but doesn't know where. The picture is not as finely detailed as a CT or MRI scan, but it can provide helpful information about your whole body. Some machines can perform both a PET and CT scan at the same time (PET/CT scan). The radiologist can compare areas of higher radioactivity on the PET with the appearance of that area on the CT. This is the most common type of PET scan used in patients with breast cancer.
This test can be useful in looking for cancer that has spread to distant organs, but it is not as helpful in looking for small deposits of cancer cells in the lymph nodes under the arm (axillary lymph nodes). PET scans are most often ordered for patients with large tumors or when the doctor suspects the cancer has spread.
For a PET scan, glucose (a form of sugar) that contains a radioactive atom is injected into the blood. Because cancer cells in the body are growing rapidly, they absorb large amounts of the radioactive sugar. After about an hour, a special camera is used to create a picture of areas of radioactivity in the body.
Last Medical Review: October 10, 2014 Last Revised: January 26, 2016