Bowel cancer - What are the symptoms?

You might not have symptoms in the early stages of bowel cancer. It usually starts by growing slowly on the inside wall of the bowel.

Some of the things you might notice are:

A change in your bowel habits that lasts for six weeks. You might have looser bowel movements or diarrhoea, need to go more often or become constipated [1]
Blood (either bright red or dark spots) in your stools. But most people with blood in their stools have piles (haemorrhoids), not cancer
Your bowel might feel as though it doesn't empty properly
You might have painful cramps, bloating and wind in your lower stomach
You might feel tired and look pale (you may be anaemic)
You might feel sick
Your stools might be narrower than usual (because the cancer has made the bowel narrow)
You might lose your appetite.

These symptoms are often due to things that aren't bowel cancer. But you should see your doctor if you are having them, particularly if you are over 45 or if a close family member has had bowel cancer. This is when the risk of bowel cancer rises. If you do have bowel cancer, the sooner you get treatment, the better your chances of surviving.

Younger people are more likely to notice their symptoms, but older people are more likely to see their GP quickly.[2] Around 1 in 4 people don't go to their doctor until the cancer has blocked their bowel and they need urgent treatment.

References

Scottish Intercollegiate Guidelines Network. Management of colorectal cancer. Scottish Intercollegiate Guidelines Network guideline No. 67. 2003. Available at: http://www.sign.ac.uk/guidelines/published/numlist.html (accessed on 2 July 2007).
Mor V, Masterson-Allen S, Goldberg R, et al. Pre-diagnostic symptom recognition and help seeking among cancer patients. Journal of Community Health. 1990; 15: 253-266.

Glossary

haemorrhoids: Haemorrhoids are swollen veins in the anus. Sometimes you can see or feel them and sometimes they are inside the anus. Haemorrhoids can hurt and bleed. They usually happen when you strain a lot to pass a stool.
anaemia: Anaemia is caused by having too few red blood cells. People with anaemia look pale and get tired easily, among other things.

This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.