PET-CT Scan for Bowel Cancer

A PET-CT scan may be used in some bowel cancer cases to give doctors more information about cancer activity and whether cancer has spread. It combines two types of imaging: PET, which looks at activity in the body, and CT, which creates detailed pictures of body structures.

This article is for general information only. Your doctor or specialist team can explain whether a PET-CT scan is needed in your case.

What Is a PET-CT Scan?

A PET-CT scan combines a CT scan and a PET scan. Cancer Research UK explains that it can give detailed information about cancer. The PET part uses a radioactive tracer, while the CT part creates detailed images of the body. :contentReference[oaicite:0]{index=0}

Why PET-CT May Be Used

In bowel cancer care, PET-CT may be used in selected situations, such as when doctors need more information about possible spread, unclear scan findings or treatment planning. It is not always needed for every person with bowel cancer.

For broader staging information, read our Staging Bowel Cancer article.

How to Prepare

Your imaging team will give you instructions before the scan. You may be asked not to eat for a period of time before the test. You should tell the team if you have diabetes, are pregnant, may be pregnant or are breastfeeding.

Follow the instructions from your hospital or imaging centre carefully, because preparation can affect the scan quality.

What Happens During the Scan?

You may receive a small amount of radioactive tracer, usually through a vein. After waiting for the tracer to move through the body, you lie on a scanning table while images are taken.

The scan is usually painless, but lying still may feel uncomfortable for some people.

Possible Risks

A PET-CT scan involves exposure to a small amount of radiation. Your healthcare team will only recommend it when they believe the benefits outweigh the risks.

If you have concerns about radiation, allergies, diabetes or pregnancy, ask your medical team before the scan.

Final Thoughts

A PET-CT scan can help doctors gather more information in selected bowel cancer cases. Ask your doctor why the scan is recommended, what it may show and when you will receive the results.

For more test information, visit our Further Tests After Bowel Cancer Diagnosis guide.