PET/CT Scans

GENERAL

A PET/CT scan uses radioactive glucose to produce 3D colour images, which show the function of the human body. PET stands for Positron Emission Tomography.

RADIOACTIVE GLUCOSE?

A variety of Radiopharmaceutical Products are used:

• ¹⁸F-FDG
• ⁶⁸Ga-DOTATATE
• ⁶⁸Ga-PSMA

⁶⁸Ga-DOTATATE

⁶⁸Ga-DOTATATE is used in the assessment of somatostatin receptor expressing tumours such as gastroenteropancreatic neuroendocrine tumours (NETs). In. addition to GEP NETs, there are many subtypes of NET including pheochromocytomas, paragangliomas, medullary thyroid cancers, Merkel cell cancer and bronchial carcinoid that can be imaged with ⁶⁸Ga-DOTATATE

PREPARATION

• You don’t need to fast before the study
• There are medications that may interfere with ⁶⁸Ga-DOTATATE uptake and should be stopped for a period of time before your scan date. These include:
  • 1. Monthly Octreotide LAR (also known as Sandostatin LAR) – should be stopped for a month
  • 2. Monthly Lanreotide (also known as Lanreotide Autogel) – should be stopped for a month
  • 3. Short-acting Octreotide injections (usually 2-3 per day) – should be stopped for 24 hours

⁶⁸Ga-PSMA

⁶⁸Ga-PSMA PET/CT is a non-invasive, diagnostic technique used to image prostate cancer with increased expression of prostate specific membrane antigen (PSMA).

PREPARATION

• You don’t need to fast before the study and can take all your medication.
• It is important to be well-hydrated before the study and during the uptake time

WHAT DOES THE PROCEDURE ENTAIL?

On arrival:

• The radioactive tracer will be administered through a vein
• This is followed by an uptake period of 60 minutes to allow the tracer to be taken up by the tissues
• You will be asked to urinate prior to image acquisition
• The scan will take approximately 30 minutes

Following the scan:
Once the PET/CT scan is complete, you will have to wait an hour before you can leave. During this hour we will prepare the images and a disc you need to take to your referring physician. The PET physician also needs to make sure there’s no need for any additional scans to assist them with the PET report.

Make sure you drink plenty of water or other fluids throughout the day.

The results of your scan will be interpreted by a trained nuclear medicine physician and radiologist and your physician will receive a written report approximately 48 hours after completion of the study.

Please contact your physician to discuss the results.

HOW DO I PREPARE FOR MY PET/CT SCAN

Your preparation for the PET/CT scan, will depend on the Radiopharmaceutial product that will be used. This will be discussed in detail on booking your PET scan.

WHAT ARE THE RISKS

Nuclear Medicine uses radioactivity to diagnose and treat medical conditions. The risk from diagnostic doses is usually very low. Radiation involved in Nuclear Medicine is far less than that of conventional x-rays.