If you’ve been diagnosed with breast cancer, your doctor will talk with you about the stage of the cancer. Stage is usually expressed as a number on a scale of 0 through IV — with stage 0 describing non-invasive cancers that remain within their original location and stage IV describing invasive cancers that have spread outside the breast to other parts of the body.
Knowing the stage of the breast cancer is important because it helps you and your doctor understand your prognosis (the most likely outcome of the disease) and make decisions about treatment.
Doctors sometimes have a hard time staging breast cancer that has spread extensively in the breast or to the nearby lymph nodes (called “locally advanced breast cancer”). In a recent study, researchers tested whether using an imaging test called the PET/CT improved the staging of this kind of cancer.
The study was published in The Journal of Nuclear Medicine in January 2013.
Over the course of 5 years, the researchers studied 117 patients with locally advanced breast cancer. The patients underwent conventional imaging tests, such as mammography, ultrasonography, and breast magnetic resonance imaging. The researchers determined the stage of each patient’s beast cancer based on the results of these tests.
Then the patients had a PET/CT, a test that combines positron emission tomography (PET) and computed tomography (CT) imaging.
- PET detects cancer by obtaining images of the body’s cells as they work. (A special camera scans the body and identifies areas where cells are suspiciously active, which can indicate cancer.)
- CT imaging uses an X-ray technique to create detailed pictures of the inside of the body. (A CT scan can show whether or not the cancer has moved into the chest wall, and if so, where in the body it has spread.)
Specialists who had no knowledge of the results from the conventional imaging tests reviewed the results of the PET/CT.
When the researchers compared the results of the two different approaches, they found that PET/CT provided more accurate information about each patient’s cancer than the conventional imaging tests:
- The PET/CT successfully identified all of the primary tumors in the 117 patients (35 with locally advanced inflammatory breast cancer and 82 with locally advanced noninflammatory breast cancer).
- The PET/CT found lymph node involvement in 32 more patients than the conventional imaging did.
- The PET/CT also found that the cancer had spread to distant areas in the body (such as into bone, the liver, or a lung) in 43 patients, compared to just 28 patients by conventional imaging.
- The findings from the PET/CT changed the stage of 61 of the 117 patients (more than 50%). As a result, the recommended treatment changed for these patients.
PET/CT isn’t used routinely to evaluate breast cancer. It’s an expensive, sophisticated test that requires special expertise, and it’s not available in all centers. But as these study results show, PET/CT can provide information that may allow doctors to better tailor treatment to the individual needs of each patient.
Although PET/CT is still being studied, you may want to ask your doctor whether this test would be useful in your treatment planning. If the answer is “yes,” you can ask where PET/CT is available in your area.
For more information on staging in breast cancer, visit the Breastcancer.org pages on Stages of Breast Cancer.