One hallmark of cancer cells is that they require excessive amounts of glucose to fuel their high energy needs due to their rapid division.
- Glucose is transported inside our cells via glucose transport proteins from the GLUT family of transport proteins; hence, cancer cells possess a higher number of these transport proteins than normal cells ( especially GLUT1 and GLUT2 transport proteins)
- This allows more of the fluorodeoxyglucose (FDG) to get absorbed by cancer cells than other normal cells within the body, and thus allowing a higher concentration of the radioactive isotope (fluorine-18) to be present in the cancer cells (which will result in more gamma ray detection and ultimately, a clearer computerized construction of that particular tissue)
Monitoring the Growth of Known Cancerous Tissue
A PET scan can also be helpful in monitoring the progress of a known cancerous tissue. The imaging can let the oncologist know changes in size and location of the pre-existing cancer. An increased FDG uptake by a known cancerous tissue in a PET scan can also indicate one or more of the following:
--> progression to a higher stage of that particular cancer ( spreading out further in the same organ or metastasizing to different parts of the body )
--> failure or low effectiveness of an already employed treatment for the cancer ( for example, resistance to chemotherapy )
--> recurrence of the cancer after a previous removal of the cancer
--> progression to a higher stage of that particular cancer ( spreading out further in the same organ or metastasizing to different parts of the body )
--> failure or low effectiveness of an already employed treatment for the cancer ( for example, resistance to chemotherapy )
--> recurrence of the cancer after a previous removal of the cancer