A PET/CT scan combines positron emission tomography (PET) and computed tomography (CT) images. PET images show the function of cells in the body. CT images show details of body anatomy such as vessels, lymph nodes, and organs. Alone, PET and CT are each effective for a wide variety of applications. When PET and CT scans are combined, the fused images help doctors accurately diagnose, stage and treat cancer. PET/CT scans may reduce the need for biopsy or surgery.

How should I prepare for a PET/CT?

In preparation for a PET/CT exam, you will be required to have nothing to eat or drink several hours before the scan. If you are diabetic, you may be given special instructions. The patient receives a small injection of radioactive tracer 60 minutes before the scan and asked to rest comfortably while the radioactive tracer moves through the body. Then the patient is brought to the scanner for the exam. The length of the exam depends upon the body area being scanned but ranges from 30- 45 minutes.

PET/CT can help determine:

  • Size and location of growth
  • Whether the cancer is spreading
  • The best form of treatment
  • Whether therapy is working
  • Whether there has been a recurrence