PET scans in breast cancer care

It is not a replacement for mammography, breast ultrasound, MRI, or biopsy. The oncology team selects it for a specific clinical question, such as checking suspected spread or clarifying findings elsewhere in the body.

The scan combines two kinds of information. CT shows body structures, while PET detects the distribution of a small amount of FDG radiotracer, a glucose-like material. Areas using more glucose may appear more active on the images.

Increased FDG uptake is not automatically cancer: infection, inflammation, healing tissue, muscles, and some normal organs can also take it up. A specialist interprets the pattern alongside pathology, earlier scans, treatment history, and current symptoms.

Follow the imaging centre's instructions about food, drinks, exercise, and medicines because blood glucose and muscle activity can affect FDG distribution. Tell the team if you have diabetes, are pregnant or could be pregnant, are breastfeeding, have allergies, or find it difficult to lie still.

After the injection, you will rest quietly before lying on the scanner table. Remove metal items when instructed. Bring relevant scan reports and confirm whether contrast material will also be used, since that can require additional safety questions.

Tell staff immediately if you feel short of breath, faint, develop facial swelling, widespread itching, or feel unwell during the injection or scan. If contrast is used, the imaging team will explain which delayed symptoms should prompt a call.

Once home, seek urgent care for breathing difficulty, throat swelling, collapse, or rapidly worsening symptoms. For soreness, increasing redness, or swelling around an injection site, contact the imaging centre or treating team for advice.

Ask what decision the PET-CT is expected to inform and how its findings will be compared with biopsy results and other imaging. Find out whether treatment could alter the scan timing or interpretation.

Before leaving, confirm when the report should be available, who will discuss it, and what the next step would be if an area of increased uptake needs targeted imaging or tissue sampling.