The large bowel can be divided into the colon, the rectosigmoid, and rectum. The colon starts where the small bowel ends. It is 1.5-1.8 metres long when stretched. The rectum forms the final 10-15 cm of the large bowel, opening to the outside at the anus. The rectosigmoid is the transitional zone between the colon and the rectum 1. In the Netherlands, colorectal cancer is the third most common cancer (14%) among males, after prostate (21%) and lung cancer (16%), and it is the second most frequent tumor (13%) among females after breast cancer (33%). In 2003, almost 10.000 patients were diagnosed with the disease; in this year, 4.500 patients died of the disease 1. The incidence in the Netherlands compared to other European countries, is relatively high, and ranks in the top-10 2. Worldwide, colorectal cancer accounted for about 1 million of new cancer diagnoses in 2002, representing nearly 10% of all new cancers among both men and women 2. It occurs more frequently in the industrialised world. The disease rarely occurs before age 40, the risk of colorectal cancer becomes highest around age 70 1. The lifetime risk to develop colorectal cancer is 5.6% in the industrialised world 1, 3. As a percentage of total mortality, the risk of dying from colorectal cancer in