Colorectal cancer is one of the most important cancers to study. Many of the advances that have been made in understanding cancer come from the study of colo-rectal cancer. It is one of the most common cancers. It is the second commonest cancer in the Western world. It causes 10% of cancers in Ireland. There are 1800 new cases of colorectal cancer per year in Ireland. Importantly surgery offers a potential cure in 50%.
Cancers are broadly divided into those that affect the cells of the blood (leukemias, lymphomas) and those that affect the solid organs. Most of the tumors of the solid organs are difficult to treat and have a poor outcome however the two most treatable of these cancers are breast cancer and colo-recatal cancer. Colo-rectal cancer on average has a more favourable outcome than lung, esophageal, gastric and pancreatic cancers.
Colonic cancer is quite similar to rectal cancer in many ways but there are some important differences. Cancer of the anal canal is markedly different.