A Radiologist explains the various radiotracers used in PET-CT imaging procedures.
Irving, TX – January 17, 2020 – Positron emission tomography (PET) is a radionuclide molecular imaging technique for detecting, measuring, and monitoring biological activities in the body. It uses positron-emitting radiotracers that are targeted to specific antigens, receptors, enzymes, or transporters. PET images are interpreted by radiologists to confirm the biochemical activity at a disease site.
“PET is used in combination with computed tomography (CT) to check for tumor metabolism in oncology,” explained the radiologist. “It helps in research and patient management by using radiotracers to enhance the state of cancers and other diseases in imaging. Radiotracers use biologically active molecules such as water, glucose, and ammonia.”
Here are some of the positron-emitting tracers used in PET-CT imaging to guide disease diagnosis and help monitor patient’s response to treatment:
- FDG PET/CT – This is the most commonly used metabolic marker in oncologic PET-CT imaging. Known as fluorodeoxyglucose (18F FDG), the radiotracer helps in diagnosing cancer. It also assists oncologists to detect cancer spread and measure the effectiveness of treatment.
- Sodium Fluoride PET/CT – It is called the (18F)NaF radiotracer used for bone imaging. This tracer is highly sensitive and helps to detect any skeletal abnormalities in a patient.
- Amyloid PET/CT – This is used to estimate the density of amyloid plaque in patients with Alzheimer’s disease, cognitive impairment, and other factors that are causing cognitive decline. The biomarkers used include (18F)florbetapir and (18F)florbetaben.
- 13N-ammonia – This tracer is used in myocardial perfusion imaging. Its high sensitivity helps to detect occlusive coronary artery disease and evaluate the effectiveness of treatment.
- (68Ga)Dotatate – This radiotracer is used in PET/CT imaging to detect, treat, and monitor neuroendocrine tumors in patients.
“High concentrations of radiotracers on PET/CT indicate the presence of disease, including cancer,” continued the radiologist. “Using the biomarkers can help to determine if cancer has spread to other parts of the body. If this is the case, the PET/CT scan can help to stage it and find the best treatment option. You should discuss with your doctor about any risks when considering PET/CT scanning.”