Together, the colon and rectum make up the large intestine, a question mark-shaped bowel four feet in length. ... Colon cancer is more common. An estimated 95,000 new cases of colon cancer are diagnosed each year, compared to 39,000 cases of rectal cancer, according to the American Cancer Society. 3 Questions about colorectal cancer treatment: What are colorectal cancer treatment options? What types of doctors will I see during treatment? What does it mean that cancer has metastasized? Share if you like!