PET is useful in diagnosing many different kinds of cancer: lung, lymphoma, melanoma, head and neck, colorectal and recurrent brain cancer. A PET scan can show where a tumor is located, and distinguish between a tumor that is malignant or benign. Often, PET can spot cancers earlier than is possible with any other kind of test. And with early detection, your doctor's chances for successful intervention are greatly increased.
PET is also used in "staging" many types of cancers, including lung, breast and cervical cancer, by showing the full extent of the disease, and if and where it has spread, anywhere in your body. In this way PET can guide your physician in deciding which treatment options - including surgery, radiation and chemotherapy - are right for you. PET is also a highly accurate way to check for recurrence of cancer; it can differentiate between recurrent cancer and scarring from surgery or radiation.
Doctors also use follow-up PET scans to see whether treatment therapies are working. Often, PET may show that a tumor is successfully responding to treatment far earlier than other diagnostic tests, which depend on changes in physical anatomy.