Colorectal cancer is a cancer of the colon or rectum. It is sometimes called bowel cancer or cancer of the large intestine. It is one of the most common cancers in the UK. Colorectal cancer can affect any part of the colon or rectum. In general, the more advanced the cancer (the more it has grown and spread), the less chance that treatment will be curative.
As the cancer cells multiply they form a tumour. The tumour invades deeper into the wall of the colon or rectum. Some cells may break off into the lymph channels or bloodstream. The cancer may then metastasise (spread) to lymph nodes nearby or to other areas of the body, most commonly the liver and lungs.
The most common symptoms are:
- Bleeding with passing motion
- Passing mucus with the faeces
- A change from your usual 'bowel habit'. This means you may pass faeces more or less often than usual causing bouts of of diarrhoea or constipation.
- A feeling of not fully emptying the rectum after passing faeces.
- Abdominal pains.
- Bowel blockages
Your surgeon will examine you in clinic and the lowest tumours can be felt, or seen on a short telescope used in outpatients (rigid sigmoidoscope). However in most cases a test on the large bowel will be required to assess the whole colon and rectum. This is usually a colonoscopy, but can also be a specialised CT scan. If a tumour is found it is biopsied for diagnosis, and this can only be done via the colonoscope. Treatment Surgery is the mainstay of treatment to try and cure bowel cancer. The segment of bowel with the cancer in it can be removed and the ends usually rejoined. In some cases a stoma is needed either temporarily or occasionally permanently (the bowel brought to the abdominal wall and drained to a pouch).Surgery can be performed by open technique or keyhole technique in most cases.