Colorectal cancer occurs in the large intestine (AKA the colon)or rectum. Abnormal growths (called polyps) can form in there, and over time, these polyps can turn into cancer. So how do you know if you have polyps? Screening testscan find them, and if you find them early enough, they can be removed beforebecoming cancerous. Learn more below about your options when it comes to screening and early detection.