What Is Colorectal Cancer?
Cancer is a disease in which cells in the body grow out of control. Colorectal cancer is cancer that occurs in the colon or rectum. The colon is the large intestine or large bowel. The rectum is the passageway that connects the colon to the anus.
Screening Saves Lives
Colorectal cancer is the second leading cancer killer in the U.S. among cancers that affect both men and women. But it doesn’t have to be. Routine screening for colorectal cancer beginning at age 45 can save lives!
Here’s how:
• Colorectal cancer usually starts from precancerous polyps in the colon or rectum. A polyp is a growth that shouldn’t be there. Over time, some polyps can turn into cancer.
• Screening tests can find precancerous polyps, so they can be removed before they turn into cancer. Screening tests can also find colorectal cancer early, when
treatment works best.
You May Be at Increased Risk If:
• You or a close relative have had colorectal polyps or colorectal cancer.
• You have inflammatory bowel disease, Crohn’s disease, or ulcerative colitis.
• You have a genetic syndrome such as familial adeno-matous polyposis (FAP) or hereditary non-polyposis colorectal cancer (Lynch syndrome).
People at increased risk for colorectal cancer may need earlier or more frequent tests than other people. If you think you may be at increased risk, talk to your health care provider about the routine screening tests that are right for you.
Last modified: March 17, 2026
