Bowel polyps are small growths on the inner lining of the colon (large bowel) or rectum. They are common, affecting 15-20% of the UK population, and don’t usually cause symptoms. Polyps are usually less than 1cm in size, although they can grow up to several centimetres. There are various forms. Some are a tiny raised area or bulge, known as a sessile polyp. Some look like a grape on a stalk, known as a pedunculated polyp. Some take the form of many tiny bumps clustered together
Bowel polyps are not usually cancerous, although if they’re discovered they’ll need to be removed, as some will eventually turn into cancer if left untreated. Some people just develop one polyp, while others may have a few. They tend to occur in people over the age of 60.
Bowel polyps are caused by an abnormal production of cells. The lining of the bowel constantly renews itself, and a faulty gene can cause the cells in the bowel lining to grow more quickly. There may be a family tendency towards developing bowel polyps Early cancer doctor.
Most people with polyps won’t be aware of them as they produce no symptoms and are often discovered by accident. However, some larger polyps can cause:
A small amount of rectal bleeding (blood in your stool)
Mucus to be produced when you open your bowels
Diarrhoea or constipation