Frequently Asked Questions
Q: I just found out that I have breast cancer! Do I need to do a PET scan?
- If the cancer is small or very early stage 0 – I with no evidence of spread to lymph nodes, then you do not need a PET scan. Only larger cancers with evidence of spread to lymph nodes might need a PET scan to make sure there is no spread to other organs. Thus, patients with more aggressive cancer or advanced cancer might need a PET scan.
Q: What is a PET scan and what does it show?
- PET stands for Positron Emission Tomography and uses radioactive glucose to show metabolically active tumors and areas of tumor spread. Aggressive tumors tend to be more metabolically active and take up more of the radioactive glucose.
Q: I have breast cancer that has been removed and I received chemotherapy and radiation. I never had a PET scan. Do I need one now?
- Your doctor can order PET scan only if you have any symptoms or test that may indicate the cancer is coming back or spreading. Sometimes, PET scans are needed to clarify a finding on other imaging modality like CAT scan, MRI or ultrasound, to see if the finding is cancerous or not.
Q: A friend of mine tells me that she had a PET scan and then she received more treatment and repeated PET scan. Why did she have a repeated PET scan?
- PET scan is a very good imaging modality to evaluate tumor response to treatment. So, it helps the clinicians find out if they are using the correct treatment for the kind of cancer or sites of spread or they need to change the treatment plan. The first PET scan usually serves as a baseline before the initiation of treatment and the second one is to evaluate the response to treatment.
Q: My doctor ordered a PET scan for me and I don’t know what to expect?
- PET scan is an easy test. You will have to fast for at least four hours before the test. You also need to eat a low carbohydrate diet the day prior to the scan. Before starting the PET scan you will be injected intravenously with glucose attached to radioactive tracer which does not have any side effects. Then you will stay in a quiet room for 30 minutes before starting the scan. The PET scanner is a ring-shaped machine that you will go through to take pictures just like a CAT scan. The machine is quiet and will never touch you throughout the scan. Imaging typically takes 30 minutes to complete.
Q: What is sentinel lymph nodes?
- It is the lymph node that receives drainage from the breast cancer area and thus would be the first lymph node(s) the cancer would spread to.
Q: Where are the sentinel lymph nodes found?
- Sentinel lymph nodes are usually in the armpit area or behind the sternum (breast bone).
Q: My surgeon ordered a sentinel lymph node test for me and I don’t know what to expect? Is it painful?
- Lymph node mapping test is usually done on the same day or prior day of the operation for breast cancer resection.
- Usually, a small amount of radioactive material is injected into the breast close to the cancer area or under the nipple, the radioactive material has no side effects. It might be slightly painful but not as bad as the breast cancer biopsy.
- Subsequently, images of the chest will be obtained and the camera will not touch you at all.
- The radioactive injection will go to the sentinel lymph node(s) and will be seen on the images.
- During the operation, the surgeon will look for these radioactive sentinel lymph nodes and remove them. Then, they are sent to Pathology lab, to look under the microscope for any tumor cells that spread to the sentinel lymph node(s).
Q: What happens if the sentinel lymph nodes show spread of cancer?
- The surgeon might re-operate and remove more lymph nodes or you might receive chemotherapy or radiation therapy.