Bowel Cancer explained 

How common is bowel cancer?

Each year, 35,000 people in Britain are diagnosed with cancer of the bowel, that is to say cancer of the colon and rectum. This makes it one of the commonest cancers. But unlike some malignant tumours, bowel cancer can often be cured by surgery and new treatments are being introduced to make survival even more likely. The earlier the bowel cancer is diagnosed, the greater the likelihood of cure.

How does bowel cancer start?

Throughout our lives, the lining of the bowel constantly renews itself. This lining contains many millions of tiny cells which grow, serve their purpose and then new cells take their place. Each one of these millions of cells contains genes which give instructions to the cell on how to behave. When genes behave in a faulty manner, this can cause the cells to grow too quickly which eventually leads to the formation of a growth that is known as a polyp. This is the first step on the road towards cancer.

 
What is a polyp?

A polyp, or more strictly a particular type of polyp called an adenoma, starts as a tiny bump on the inside of the bowel. At first, the genes give instructions for the polyp to grow in an orderly manner. Some polyps remainvery small throughout their lives while others grow slowly larger. At this stage, the lump is still benign. Most polyps remain benign throughout life but about one in 10 will turn into a cancer. Broadly speaking, the larger a polyp, the more likely it is to become cancerous – although cancer is unusual if the polyp is less than 1cm in diameter. We believe that all malignancies of the bowel probably start off as benign polyps. We know that removing benign polyps can prevent cancer developing later.