Tests to Find Cancer in the Bowel

Tests to find cancer in the bowel may be used when someone has symptoms, an abnormal screening result or risk factors that need investigation. These tests can help doctors check for polyps, bleeding, abnormal tissue or cancer in the colon or rectum.

This article is for general information only. If you have symptoms or concerns, speak with a doctor for personal medical advice.

Stool Tests

Stool tests can look for hidden blood or other signs that may need follow-up. These tests are often used in screening programs or when doctors need more information.

A positive stool test does not always mean cancer, but it usually needs further investigation.

Colonoscopy

Colonoscopy is a common test used to examine the large bowel. It can help doctors find polyps, inflammation, bleeding or cancer. Biopsies can also be taken during the procedure.

For more detail, read our Colonoscopy and Biopsy for Bowel Cancer article.

Flexible Sigmoidoscopy

Flexible sigmoidoscopy examines the rectum and lower part of the colon. It does not look at the entire colon, but it can be useful for some symptoms or screening approaches.

Visit our Flexible Sigmoidoscopy for Bowel Cancer Checks guide for more information.

Biopsy

If an abnormal area is seen during colonoscopy or sigmoidoscopy, a biopsy may be taken. A biopsy is examined under a microscope to confirm whether cancer cells are present.

Scans After Diagnosis

If bowel cancer is found, scans such as CT, MRI or PET-CT may be used to check the stage and plan treatment.

For staging information, read our Further Tests After Bowel Cancer Diagnosis article.

Final Thoughts

Tests to find cancer in the bowel can include stool tests, colonoscopy, flexible sigmoidoscopy and biopsy. The right test depends on symptoms, screening results and medical history.

If bowel cancer is found, your healthcare team may recommend further tests to understand the stage and plan treatment.