A small cancer that is contained in a polyp can be removed using a colonoscopy. If there is no evidence that the cancer has spread further, then treatment, such as surgery, may not be needed.

For more extensive cancers, surgery is the most common treatment. Chemotherapy and radiation therapy may be combined with surgery, if the cancer has spread beyond the lining of the colon or rectum. In recent years, several new drugs have also been used to treat patients with colorectal cancer.