Your doctor may want to check you for distant metastatic disease; that is, whether or not the cancer has spread to any other part of your body, particularly if your cancer is large or your lymph nodes are suspicious. Staging, or a metastatic work-up, is focused on finding cancer in the sites that are most often involved if cancer has spread beyond the breast and lymph nodes.
One of the most common places for breast cancer to go (outside of the breast and lymph nodes) is to the bones. A bone scan helps to find this cancer. A radioactive tracer is injected into your veins and a series of pictures are taken that help us to find cancer in any bone in your body. If something “lights up," your doctor may recommend further X-ray tests to look at that bone in more detail.
Your lungs, liver, adrenal glands, and other abdominal and pelvic organs could also be affected by distant metastatic disease (i.e., cancer that has spread beyond the breast and lymph nodes). A CT scan may be done of your chest, abdomen, and/or pelvis. In this test, you lie on your back on a hard table, which is then moved into a donut-like scanner. The tube is wider (i.e., less claustrophobic) and less noisy than an MRI. A contrast agent may be injected into your vein, and a series of pictures taken; this only takes a few minutes.
Sometimes, your doctor may recommend a PET-CT, which adds a PET scan to the CT scan described previously. The PET part is one in which a radioactive-labeled sugar is injected into your vein. Areas that are rapidly growing take up the sugar to use as fuel, and “light up." This can help us decide whether an x-ray detected spot is more or less likely to be cancer. PET scans require a significant amount of disease to be present in order to be abnormal, and therefore we usually will do a bone scan and a CT scan of your chest, abdomen, and pelvis instead.