Overview
Colorectal cancer affects the large bowel and rectum and usually grows slowly from small growths called polyps over many years. Because it develops so slowly, it is one of the most preventable and treatable cancers when caught early through attention to symptoms and, where advised, screening. A lasting change in bowel habit, blood in the stools, or unexplained weight loss should always be checked rather than blamed on piles alone.
Symptoms
- A lasting change in bowel habit — looser stools or more frequent
- Blood in the stools or bleeding from the back passage
- A feeling of not fully emptying the bowel
- Cramping belly pain or bloating
- Unexplained weight loss and tiredness from anaemia
When to see a doctor
See a doctor for a lasting change in bowel habit, blood in the stools, or unexplained weight loss — do not assume bleeding is only piles.
Causes
Growth of bowel polyps into cancer over years, with risk from age, family history, a low-fibre and high red-meat diet, obesity, smoking and long-standing bowel inflammation.