A positron-emissions tomography or PET scan is an X-ray that can find cancer, determine how advanced it is and examine the effectiveness of treatment. If an X-ray detects a spot in a lung, a PET scan determines if surgeries, biopsies or other treatments are needed. PET scans use radioactive tracers attached to glucose to discover areas of the body that are using increased glucose, which can signify cancer.
Attend a training course. Learn to read a PET scan report at PET and CT image-interpretation training. This course is available through hospitals and postsecondary institutions and consists of classwork and testing. Physicians and X-ray technicians must be able to read the results of scans, as well as communicate their findings to patients.
Check for "hot spots." A hot spot is a portion of the PET scan that alerts you to an area of the X-ray that shows the body using extra glucose. Only a trained eye will be able to determine where these hot spots appear.
Determine the values. Not all hot spots are an indication of cancer. Some are a sign of normal tissue that is highly metabolic. Physicians determine the difference by using the Standard Uptake Values scale, which measures brightness of hot spots. These values, referred to as SUVs, range from zero to 15. Any hot spot that measures more than 2 has the potential to be cancerous.
Make a diagnosis. SUVs from 2 to 3 are likely normal tissue. Readings from 10 to 15 have a higher risk of being cancerous. However, further testing may be needed.
Discuss the findings of the PET scan with the patient. If tumours are discovered, the scan may or may not indicate whether the tumour is cancerous or benign. A biopsy may be needed so it is important that a patient is aware of all options.