390487 08: (FILE PHOTO) A doctor goes over a patient''s x-ray, screening for colon cancer. There is no single cause of colon cancer. Cancer of the colon and rectum accounts for 15% of cancer deaths. (Photo by American Cancer Society/Getty Images)
390487 08: (FILE PHOTO) A doctor goes over a patient''s x-ray, screening for colon cancer. There is no single cause of colon cancer. Cancer of the colon and rectum accounts for 15% of cancer deaths. (Photo by American Cancer Society/Getty Images)