Bowel Cancer

Overview

Bowel cancer is a cancer that starts in the large intestine (colon) or the rectum. It is sometimes called colorectal cancer. It often begins as small growths called polyps, which may turn into cancer over time.

Yes. In the UK, about 42,000 people are diagnosed with bowel cancer each year. It is the fourth most common cancer in the UK.

It mainly affects people over 50, but it can occur at any age. You have a higher risk if it runs in your family, if you have inflammatory bowel disease, or if you smoke, drink alcohol heavily, or are overweight.

Symptoms

Common symptoms

• A persistent change in your bowel habits, such as going more often or less often
• Blood or mucus in your stools (poo)
• Frequent abdominal pain, discomfort, or a lump in your tummy
• Unexplained weight loss
• Feeling very tired for no clear reason

Symptoms in children

• Bowel cancer is extremely rare in children. If a child has symptoms like a lasting change in bowel habits or blood in their stools, it is almost always due to something else. Still, any persistent bowel symptoms should be checked by a doctor.

Symptoms in older adults

• Older adults may notice new or worsening constipation, loose stools, blood in the stool, or a feeling of not fully emptying the bowel. These symptoms should not be dismissed as a normal part of ageing.

Causes

Main causes

• Bowel cancer happens when the DNA inside the cells lining the bowel becomes damaged, causing them to grow out of control. The exact cause of this damage is not always clear.
• Most bowel cancers start from a polyp, a small clump of abnormal cells on the inner wall of the bowel.

Risk factors

• Age over 50
• A family history of bowel cancer or polyps
• Personal history of inflammatory bowel disease (such as ulcerative colitis or Crohn's disease)
• A diet high in red and processed meat and low in fibre
• Being overweight or having obesity
• Smoking and drinking alcohol

When to see a doctor

See a doctor urgently if:

• If you have blood in your stool, a persistent change in bowel habits lasting more than 3 weeks, or unexplained weight loss, see a GP today or the next day.
• If you have any of the emergency symptoms listed above, call your local emergency number without delay.

Book a routine appointment if:

• If you are aged between 50 and 74 and are offered bowel screening, take part.
• If you have a family history of bowel cancer, talk to your GP about whether you need earlier or more frequent checks.

Diagnosis

Your GP will ask about your symptoms, your medical history, and any family history. They may examine your abdomen and may arrange simple tests, such as a stool test and a blood test. If the results suggest a problem, they will refer you to a specialist who will usually recommend a colonoscopy.

Tests that may be done

• Stool test (also called a FIT) – a home test to look for hidden blood in your poo
• Blood tests – to check for anaemia or other markers of ill health
• Colonoscopy – a thin, flexible tube with a camera passed into your bowel to look for polyps or tumours
• Biopsy – a small piece of tissue taken during a colonoscopy and checked under a microscope
• CT or MRI scan – to see whether the cancer has spread to other parts of the body

What to expect at your appointment

At the clinic, a specialist doctor will explain each test to you. If bowel cancer is confirmed, you will have a dedicated team, including a specialist nurse, who will guide you through the next steps. You will be given time to ask questions and decide on your treatment.

Treatment

Treatment for bowel cancer depends on the size, location, and stage of the cancer, as well as your general health. The main approaches are surgery, chemotherapy, radiotherapy, and targeted drug treatments. Your team will recommend a plan tailored to you.

Self-care at home

• Follow the advice of your healthcare team and ask when you are unsure about anything.
• Allow yourself to rest when you feel tired, especially after treatment.
• Keep a small notebook of questions and notes to bring to appointments.

Medical treatments

Surgery is the most common treatment and involves removing the tumour and sometimes part of the bowel. Chemotherapy may be given before surgery to shrink a tumour, or after surgery to lower the chance of it coming back. Radiotherapy uses high-energy beams to kill cancer cells, and may be used for rectal cancers. Targeted drug treatments work on specific changes in cancer cells. Your doctor will explain what is offered and why.

When is surgery considered?

Most people with bowel cancer have surgery. In some cases, when the tumour is very low in the rectum, the surgeon may need to create a temporary or permanent stoma (a colostomy bag). Your surgeon will discuss this with you before the operation.

Living with this condition

After treatment, your energy, appetite, and bowel habits may take time to settle. Some people have to adapt to a stoma or long-term changes in digestion. Be patient with yourself and keep a steady routine with gentle activity.

Lifestyle tips

• Avoid smoking and limit alcohol to reduce the risk of the cancer returning.
• Stay physically active with activities you enjoy, like walking, swimming, or yoga.
• Keep up with follow-up appointments and scans your team recommends.

Diet and exercise

Eat a balanced diet with plenty of fruit, vegetables, wholegrains, and fibre. If your bowel is irritated, your team or a dietitian can advise you on what to avoid. Regular exercise helps with recovery, weight control, and emotional wellbeing.

Mental health and emotional wellbeing

A cancer diagnosis can bring anxiety, sadness, fear, and stress, and these feelings may also affect your family. It is completely normal. Ask your healthcare team about counselling, or speak to your GP about local mental health support.

Prevention

You cannot prevent every case of bowel cancer, but you can lower your risk by eating a fibre-rich diet, limiting red and processed meat, staying a healthy weight, exercising, and not smoking. Screening catches polyps and early cancers, which is another important way to reduce risk.

Vaccines

There is currently no vaccine to prevent bowel cancer. Vaccines for other infections, such as hepatitis B and HPV, help prevent some other cancers, but they do not protect against bowel cancer.

Screening programmes

In the UK, adults aged 50 to 74 are offered a free at-home stool test (FIT) every two years. If you are invited, you are strongly encouraged to do it. A simple test like this can find cancer very early, when treatment is much more likely to be successful.

Complications

If left untreated

• The cancer can grow through the bowel wall and spread to lymph nodes or other organs, such as the liver or lungs.
• A large tumour can block the bowel, causing severe pain, vomiting, and inability to pass stools.
• Bowel cancer can cause ongoing bleeding, which may lead to severe anaemia and tiredness.

Long-term outlook

The outlook for bowel cancer is very good if it is found early. More than 90% of people with the earliest stage of bowel cancer survive for at least five years. With improved treatments, many people live an active life long after their diagnosis. If you are diagnosed with bowel cancer, your team will be honest about your personal outlook and will focus on the best possible outcome for you.

Find support

External links open third-party websites. Ruqelo Health is not responsible for external content. Listing an organisation does not imply endorsement.