Symptoms of bowel cancer

Common symptoms of bowel cancer (colon or rectal cancer) include blood in your poo, a change in your normal bowel habit and unexplained weight loss. 

What are the symptoms of bowel cancer?

In the video below, oncologist Rebecca and Cancer Nurse Specialist Claire talk about the common symptoms of bowel cancer.

 

Bowel cancer is a general term for cancer that starts in either the colon or rectum. It might sometimes be called colorectal cancer.

We have separate information about:

The symptoms of bowel cancer include:

  • blood in or on your poo (stools), or bleeding from the back passage (rectum) – the blood may be bright red or dark
  • a change in your normal bowel habit that happens for no obvious reason and lasts longer than 3 weeks – for example, diarrhoea or constipation
  • unexplained weight loss
  • pain in your tummy (abdomen) or back passage
  • feeling that you have not emptied your bowel properly after you poo
  • a lower than normal level of red blood cells (anaemia).
  • unexplained tiredness, dizziness or breathlessness caused by anaemia.

Sometimes the cancer can cause a blockage (obstruction) in the bowel.or rectum. You may:

  • feel constipated and bloated
  • have tummy pain
  • be sick (vomit).

What should I do if I have symptoms of bowel cancer?

These symptoms can be caused by conditions other than colon or rectal cancer. But you should always have them checked by your doctor.

Many people are embarrassed or uncomfortable discussing bowel symptoms. But doctors are used to talking about these things. They may help put you at ease.

It is important that your GP refers you to a specialist if:

  • you have symptoms that do not improve within a few weeks
  • your symptoms get worse.

They can do tests to find out what might be causing the symptoms.

Getting support

We understand that having any symptoms of what could be cancer is worrying. The most important thing is to speak to your GP as soon as possible. We are also here if you need someone to talk to. You can:

Macmillan is here to support you. If you would like to talk, you can:

Booklets and resources

About our information

This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer.

  • References

    Below is a sample of the sources used in our bowel cancer information. If you would like more information about the sources we use, please contact us at

    informationproductionteam@macmillan.org.uk

     

    National Institute for Health and Care Excellent (NICE). Colorectal cancer. NICE guideline [NG151]. Updated December 2021. Available from: www.nice.org.uk/guidance/NG151 [accessed Jan 2023].

     

    Cervantes A, Adam R, Rosello S, et al. Metastatic colorectal cancer: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up. Annals of Oncology. 2023;34(1):10-32. Available from: www.annalsofoncology.org [accessed Jan 2023].

Dr Paul Ross SME

Dr Paul Ross

Reviewer

Consultant Medical Oncologist

Guy's and St Thomas' NHS Foundation Trust

Date reviewed

Reviewed: 01 May 2024
|
Next review: 01 May 2027
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

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