2.1
Colorectal cancer is a malignant neoplasm arising from the lining (mucosa) of the large intestine (colon and rectum). Colorectal cancer is the third most common cancer in the UK, with approximately 30,000 new cases registered in England and Wales in 2002. This represents 12% of all new cancer cases in women and 14% of all new cancer cases in men. The incidence of colorectal cancer increases with age. In people between the ages of 45 and 49 years, the incidence is 20 per 100,000. Amongst those over 75 years of age, the incidence is over 300 per 100,000 for men and 200 per 100,000 per year for women. The median age of patients at diagnosis is over 70 years. The overall 5-year survival rate for colorectal cancer in England and Wales is approximately 50%; however, large differences in survival exist according to the stage of disease at diagnosis.