The advanced technology associated with PET scans can show things that no other procedures can show, significantly affecting patient's treatment. In many cases, PET eliminates the need for other invasive diagnostic procedures.
PET scans are pictures of the actual biological functioning of the human body.
PET scans on the other hand, show the actual metabolic functioning of the organs. Because PET scans are pictures of the body's chemistry, many diseases can be seen with PET, often at their earliest stages. Using cancer as an example, CT or MRI can pinpoint a lesion, but these procedures often cannot say whether its benign or malignant. With PET scanning, doctors can determine with a high degree of accuracy if it is, or is not, cancer. Cancer spreads silently in the body.