Later on, the disease may cause:

• Unexpected, painless, bleeding from your back passage, or blood in your stools. If you see blood in your stools, you should see your GP immediately. Finding a little bright red blood just on the toilet paper probably does not matter. If it continues for two or three weeks, see your GP.
  
   
• A change in your bowel habit. You may develop loose bowel motions, or you may pass a slimy substance called mucus. Sometimes you may become constipated. Look especially for constipation and diarrhoea combined. If you experience these symptoms for more than six weeks, you should see your GP. If you have these symptoms as well as others in this list, see your GP sooner.
  
   
• Pain or swelling in your abdomen (tummy/belly).
  
   
• Unexplained weight loss.
  
   
• Unexplained anaemia (thinning of the blood). This can make you feel extremely tired. It is usually discovered by a blood test done by your GP.

All these symptoms can be caused by other conditions. For example, piles often bleed.

If cancer is the cause, it needs to be discovered as quickly as possible. If it is diagnosed in the early stages, while the tumour is still only in the bowel wall, you have a 90-95% chance of a cure. However, in the UK diagnosis is not early enough for many people. Currently, only about half the people found with bowel cancer can expect, after treatment, to be free of it after five years. Being free of bowel cancer for five years is regarded as a cure.