Colonoscopy
A colonoscopy uses a long, flexible tube with a camera to examine the entire colon and rectum. During the procedure, polyps can be detected and removed—potentially preventing cancer. Recommended starting at age 45, and typically repeated every 10 years, unless you are at higher risk, have symptoms, or polyps are found.
When used as a regular screening program, colonoscopy has been associated with up to 69% reduction in colorectal cancer incidence and up to 88% reduction in mortality. While non-invasive tests continue to evolve and play an important role, particularly in expanding access and adherence, colonoscopy remains the gold standard for prevention and early detection.
Benefits
• Considered the gold standard for detecting colon cancer
• Can prevent cancer by detecting and removing precancerous polyps
• Screens the entire colon
Limitations
• Requires bowel prep and sedation
• May need time off from work and need transportation support
• Slight risk of bleeding or perforation
Stool-based Test
These tests check for hidden (occult) blood or abnormal DNA, which may indicate polyps or cancer. They are recommended for average-risk individuals starting at age 45.
Common tests include stool and DNA tests, which must be repeated more regularly.
Benefits
• Non-invasive and can be done at home
• No bowel prep or dietary restrictions
• A stool sample may detect the signs of polyps, DNA mutations, or cancer
Limitations
• May miss some polyps and cancers
• Must be done yearly with stool tests or every 3 years with DNA stool tests if normal results
• A positive result requires a follow-up colonoscopy
• DNA-based tests have more false positives
