What Is Bowel Cancer?

Bowel cancer is cancer that starts in the large bowel. The large bowel includes the colon and rectum, so bowel cancer is also often called colorectal cancer. It may be called colon cancer or rectal cancer depending on where it begins.

This article is for general information only. If you have symptoms or concerns about bowel cancer, speak with a doctor or qualified healthcare professional.

Where Does Bowel Cancer Start?

Bowel cancer can start in the colon or rectum. NCI explains that colorectal cancer often begins as a growth called a polyp inside the colon or rectum, and that finding and removing polyps can help prevent colorectal cancer. :contentReference[oaicite:7]{index=7}

Colon Cancer and Rectal Cancer

Colon cancer starts in the colon, which is the main part of the large bowel. Rectal cancer starts in the rectum, the final section of the large bowel before the anus.

Treatment can differ depending on whether cancer starts in the colon or rectum. For more detail, read our Surgery for Cancer in the Colon and Surgery for Cancer in the Rectum articles.

How Bowel Cancer May Develop

Some bowel cancers develop from polyps over time. Not all polyps become cancer, but some types can change if they are not removed.

This is one reason screening and colonoscopy can be important for prevention and early detection.

Symptoms to Know

Possible symptoms include blood in the stool, persistent bowel habit changes, abdominal pain, unexplained weight loss and ongoing tiredness. These symptoms can also have other causes, but they should be checked if they persist. :contentReference[oaicite:8]{index=8}

Read our What Are the Symptoms of Bowel Cancer? article for more information.

Diagnosis and Treatment

Bowel cancer may be diagnosed using tests such as colonoscopy, biopsy and scans. Treatment may include surgery, chemotherapy, radiation therapy, targeted therapy or supportive care depending on the stage and location.

For next steps, visit our Bowel Cancer Diagnosis and Treatment for Early Bowel Cancer guides.

Final Thoughts

Bowel cancer is a serious but often treatable disease, especially when found earlier. Screening, symptom awareness and timely medical advice are important parts of bowel cancer care.