Choline PET scan: purpose, preparation and results

The tracer is injected into a vein and taken up by cells that use choline to build cell membranes. A PET scanner detects the tracer's distribution, often alongside CT images that show anatomy. The test can reveal suspicious activity, but the images do not establish a diagnosis on their own.

Your clinician may request choline PET to look for the site of recurrent prostate cancer or to answer a specific staging question. Availability and preferred tracers vary, and another PET tracer or a different scan may suit the clinical question better.

An area of increased uptake is not automatically cancer. Normal organs, inflammation and benign processes may also take up tracer, while very small or less active tumours may not be visible. A radiologist or nuclear medicine specialist interprets the pattern alongside CT findings, previous imaging, laboratory results and treatment history.

Follow the imaging department's instructions about food, drinks and medicines because protocols can differ. Tell staff beforehand about pregnancy, possible pregnancy, breastfeeding, allergies, diabetes, kidney problems, recent procedures and any difficulty lying flat. Bring prior scans and an up-to-date medicine list if requested.

Expect an injection, a waiting period for tracer distribution and time lying still during imaging. Drink fluids and empty your bladder as directed. Afterward, ask when the report will reach the referring clinician and arrange an appointment to discuss how the result affects the care plan.

Tell staff immediately if you feel unwell during or after the injection, particularly if you develop breathing difficulty, facial swelling, widespread rash, faintness or severe pain at the injection site. These reactions are unusual but need prompt assessment. Before leaving, report anxiety, claustrophobia or pain that could prevent you from remaining still so the team can discuss safe options.

Ask why choline was selected, which body areas will be scanned and whether current treatment could affect interpretation. When reviewing the report, ask whether any uptake could have a benign explanation, whether comparison with earlier imaging changes the conclusion and whether another scan, targeted imaging or tissue sampling is needed.