PET scan radioactive tracer

A small amount of tracer is usually given through a vein. One commonly used form behaves like a sugar-related substance, so cells using more energy may appear more active on the PET images. The CT part adds an anatomical map, helping the radiology team match activity with body structures.

Tracer uptake is not specific to cancer. Infection, inflammation, recent treatment, and normal activity in organs such as the brain or bladder can also create visible areas. The radiologist considers the pattern, location, timing, and your clinical history before issuing a report. PET can help investigate conditions such as lymphoma or cancer found before its original site is clear, but it does not replace every diagnostic test.

Before the appointment, ask for the centre’s instructions about food, drink, exercise, and medicines. Tell staff about diabetes, pregnancy or breastfeeding, allergies, and recent illness. After injection, you may rest quietly while the tracer circulates; movement and talking may be limited so muscle activity does not affect the images. The scan itself requires you to stay still.

The tracer loses activity naturally and leaves the body through normal processes. Follow the service’s advice about drinking fluids, using the bathroom, and contact with others. Keep the appointment for results, because the meaning depends on the full image set and the reason for the scan.

Tell staff immediately if you feel unwell during the injection or scan. After leaving, seek urgent help for breathing difficulty, fainting, facial swelling, or widespread hives. A mild injection-site sensation should still be reported if it worsens or does not settle.

Ask which tracer you will receive, why it was selected, whether your medicines or diabetes alter preparation, and when you can resume normal routines. Ask how uptake will be distinguished from inflammation and who will explain the final report.