Imaging Tests for Breast Cancer Diagnosis
To identify breast cancer, you may need tests with scanning machines that produce images of your body. A radiologist will interpret these images to understand the precise location and size of a tumor.
At Stanford, our imaging team is recognized by the American College of Radiology as a Breast Imaging Center of Excellence. That designation means our imaging technicians specialize only in breast cancer imaging, providing deep expertise you can trust. Imaging tests may include:
Diagnostic mammograms rely on X-rays to take pictures of the breast. Diagnostic mammograms take longer than screening mammograms, because your doctor wants more information about potentially abnormal tissue that was revealed during your screening mammogram. The technician will take more images of the breast and may enlarge specific areas.
This additional information helps our radiologists and other doctors determine whether suspicious findings are actually cancer. Your doctor recommended a diagnostic mammogram because you either had a:
- Lump or other changes in your breast
- Screening mammogram that shows abnormalities
After reviewing the diagnostic mammogram, your doctor may order more tests to evaluate the suspicious tissue and confirm the diagnosis.
Also known as digital breast tomosynthesis, 3-D mammography uses X-rays to take images of the breast from several different angles. The multiple images act like thin “cross-sections” and are combined to produce 3-D images of the breast.
3-D mammograms provide clearer, more focused images that make it easier for radiologists and other doctors to find breast cancer. Studies have shown that, compared to regular mammograms, the layered imaging in 3-D mammograms can help doctors:
- Detect small cancers earlier
- Find more areas of abnormal tissue
- View tumor size, shape, and location more accurately
- Reduce instances of false positive results (results that indicate cancer when there is none)
Your doctor may recommend a 3-D mammogram if you have dense breast tissue, but any woman can benefit from this type of imaging. Please note that 3-D mammogram can be more expensive than the standard kind. Be sure to check with your health insurance provider to see if your plan covers 3-D mammograms.
A breast ultrasound test uses high-frequency sound waves to create images of the breast. Ultrasound does not use radiation and is painless. It can provide clearer images of soft tissues than mammograms.
Our doctors use ultrasound after other tests, such as a mammogram or physical breast exam, to screen for breast cancer. Breast ultrasound can:
- Show greater detail after a mammogram finds breast abnormalities
- Distinguish between different types of tissues, such as fluid-filled cysts and solid masses
- Help guide a biopsy needle to take a tissue sample and test for cancer
Magnetic resonance imaging (MRI) uses radio waves and a powerful magnetic field to create detailed, cross-sectional pictures of the breast. MRI does not use radiation.
During the diagnostic process, MRI can help us:
- Better evaluate abnormal findings on a mammogram
- Measure cancer tumors after diagnosis
- Check for other tumors in the breasts
We also use MRI with mammography as a screening tool for women at high risk of developing breast cancer. Additionally, an MRI can show how well breast cancer treatment – surgery, chemotherapy, or radiation therapy – is working by monitoring the size of the tumor to see if it is shrinking.
If you receive a diagnosis of an invasive type of breast cancer, you may need a chest X-ray. This test can show your doctor whether the cancer has spread.
A bone scan can rule out whether breast cancer has spread to your bones. Also called skeletal scintigraphy, the test uses a small amount of radioactive material to highlight any abnormal tissue, which may indicate cancer. Your doctor may recommend a bone scan if you are diagnosed with an invasive type of breast cancer.
PET and CT scans
A positron emission tomography (PET) scan is a nuclear imaging test that uses a small amount of radioactive material to highlight areas of suspicious cells. Computed tomography (CT) scans use X-ray technology to take cross-sectional images of the body. We use these technologies alone or combined, depending on the information we need from the scans.
During treatment for breast cancer, our doctors use PET scans alone to:
- Determine whether cancer has spread to the lymph nodes (small glands that filter bacteria, viruses, cancer cells, and other impurities) or other parts of the body and, if so, where
- Monitor how well cancer is responding to treatment
- See if cancer has returned after treatment
We rarely use CT scans alone to evaluate cancer in the breast. CT is helpful in examining other areas of the body to see if breast cancer has spread.
We offer combined PET/CT scanning, which takes both scans at the same time and in the same machine to keep you in the same position. This technique allows us to combine CT images of the body with PET scans that highlight possible areas of cancer.
The combined PET/CT images show the specific locations of any cancer, providing more precise information for treatment. We use PET/CT scans to:
- Stage breast cancer
- Check other parts of the body to see if breast cancer has spread there
- Monitor cancer’s response to treatment
Bone mineral density test
Your doctor may recommend a bone mineral density test before treatment for breast cancer. Breast cancer treatment can put you at a higher risk for developing osteoporosis, a condition that causes bone loss and fragile, brittle bones. Measuring your bone mineral density before treatment gives us a baseline, so we can compare later test results with initial bone loss.