Bowel cancer: The facts
- Colorectal cancer is also known as bowel cancer. It starts in the large bowel (colon cancer) or back passage (rectal cancer).
- According to the 2026 NCRI report, 2,869 people are diagnosed in Ireland annually (1,656 men; 1,213 women).
- It is the 2nd most common cancer in Irish men and 3rd in Irish women (excluding non-melanoma skin cancer).
- Excluding non-melanoma skin cancer (NMSC), it is the 2nd most common cause of cancer death in Ireland, with an average of 1042 deaths per year.
- While most common over 60, 22% of cases are diagnosed in people under 60, often before the national screening age.
The bowel and bowel cancer
The bowel is part of the digestive system, divided into the small bowel and the large bowel (colon and rectum). Food waste ends up in the large bowel, where water is absorbed before leaving the body. Bowel cancer specifically affects the large bowel.
Risks and causes of bowel cancer
While the exact cause is often unknown, several risk factors increase the chance of development:
- Age: Risk increases significantly over 50.
- Family history: Conditions like Lynch syndrome or FAP increase risk.
- Personal history: Previous polyps or colorectal cancer.
- Lifestyle: Diets high in processed meat, obesity, smoking, and high alcohol intake.
- Digestive disorders: Crohn’s disease or ulcerative colitis.
Bowel cancer symptoms
- Changes in bowel habits (diarrhoea/constipation) lasting six weeks or more.
- Blood in the stool (bright red or dark/tar-like).
- Persistent abdominal cramps, pain, or bloating.
- A lump in the back passage or abdomen.
- Sudden, unexplained weight loss.
- Constant fatigue or iron deficiency anaemia.
These can be caused by other conditions, but it is essential to see your doctor.
How you can reduce your risk
Improving your diet can help reduce risk:
- Eat more fiber (cereals, beans, fruit, veg) and oily fish.
- Eat less fat, red meat, and sugary processed foods.
- Avoid processed meats like bacon, sausages, and ham.
Lifestyle changes also matter:
- 30 minutes of moderate activity 5 times a week.
- Maintain a healthy weight and reduce alcohol consumption.
- Stop smoking (Contact HSE Quit Team at 1800 201 203).
Screening for bowel cancer
Bowel screening uses a FIT (faecal immunochemical test) to find tiny amounts of blood in the stool. It doesn’t diagnose cancer directly but indicates if further tests, like a colonoscopy, are needed.
BowelScreen offers free home tests every two years to men and women aged 57–71. To check the register, call 1800 45 45 55.
Screening results
Results arrive within four weeks. Most results are normal; if not, you will be offered a colonoscopy to investigate the presence of blood.
Treatment for bowel cancer
Treatment is based on the stage and location of the cancer. Main options include surgery, chemotherapy, biological therapy, and radiotherapy.
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