Results of a Lung Cancer PET/CT Exam

PET/CT use a small amount of a radioactive drug, which is normally FDG: a tracer in combination with a compound such as glucose. Once injected the FDG tracer travels through the body.

FDG emits signals as it travels and eventually collects in the organs targeted for examination. If an area in an organ is cancerous, the signals will be stronger (as shown on the images) since more glucose will be absorbed in those areas. Your physician or surgeon will pick up theses stronger images.

In the lungs, if the cancer has affected the nearby lymph nodes, they will take up more of the radioactive glucose. Whether or not lymph nodes are involved is a critical factor in deciding whether you can have surgery to remove the lung cancer.

CT scanning looks at the size of the lymph nodes and PET is more than 82% accurate in determining if cancerous cells are alive in that area. In a whole-body scan, the PET scan can look throughout your whole body to see if there are any clumps of the cancer cells that have spread, and the CT can build up an accurate location picture that is superimposed over the PET results, thus aiding complete accuracy in staging and location of a cancer.

The type of treatment that can be performed is based on both the type of cancer cells and the stage. If the tests show that the cancer has not spread too far, then surgery to remove it is done.

If the cancer has spread, it is treated by chemotherapy and/or radiation therapy. Lung cancer can spread to nearly anywhere in the body, but most commonly it spreads the brain, bone, and liver. After first showing the doctors where the cancer cells are, PET/CT can also see if the chemotherapy and/or radiation therapy has been effective at killing them.