PET stands for Positron Emission Tomography. In it images of body cells are captured as they work. The process involves injection of radioactive composite (sugar + small amount of radioactive material) in the body. As the cancer cells are relatively more active as compared to normal cells, they absorb the radioactive sugar. Now with the help of a special camera which scans the body, the scan captures the radioactive cancer cells on a computer monitor. These are highlighted on the screen and thus the areas with high radioactive activity are identified as suspicious cancer site. Now that the cancer site is isolated, the doctor my initiate further tests to evaluate cancer growth.
The PET scan cannot be employed for breast cancer screening in women. The PET scan can only detect small tumors. The primary purpose of PET scan is to detect the spread of cancer to the lymph nodes and to the other parts of the body. Also it can be used to assess the response of metastatic cancer to the treatment. It can also be used to evaluate the recurrence risk of a cancer.
PET scans are useful in women already diagnosed with breast cancer and is a sophisticated test with good accurate results. It primarily is a monitoring and diagnosing tool in breast cancer.