Colon cancer screenings are an essential part of health care. The lifetime risk of colon cancer is about 1 in 24. Screening used to be offered starting at age 50, but now the USPSTF, the government agency for primary care standards, has recommended that physicians offer colorectal cancer screening at age 45. The reason is that colon cancer is increasingly being found in younger adults today.
Detecting colon cancer with screening in the early stages is the most important factor for cure and survival. Only 60% of people who are eligible receive a screening test. Increasing screening to 80% could reduce deaths from colorectal cancer by 33% in 2030.
Testing need not be embarrassing, uncomfortable or inconvenient. There are both stool-based tests and direct visualization tests that patients can choose in consultation with their physicians. Factors to consider when deciding on a testing strategy include:
- The accuracy of the test
- How frequently must testing be done
- Done at home or at medical facility
- Is sedation or preparation required?
Every patient should be able to find a screening plan right for them.
Stool-Based Tests include the high-sensitivity guaiac fecal occult blood test (gFOBT), fecal immunochemical test (FIT), and stool DNA test. Both high-sensitivity gFOBT and FIT detect blood in the stool; however, they use different methods. These tests can be done at home.
Direct Visualization Tests to screen for colorectal cancer include colonoscopy, CT colonography, and flexible sigmoidoscopy. All 3 screening tests visualize the inside of the colon and rectum, although flexible sigmoidoscopy can only visualize the rectum, sigmoid colon, and descending colon, while colonoscopy and CT colonography can generally visualize the entire colon. For colonoscopy and flexible sigmoidoscopy, a camera is used to visualize the inside of the colon, while CT colonography uses x-ray images. These tests need to be done at a medical facility.
Testing Frequency depends on the test option(s) chosen:
- High-sensitivity gFOBT or FIT — 1 year
- sDNA-FIT — 1 to 3 years
- CT colonography — 5 years
- Flexible sigmoidoscopy — 5 years
- Flexible sigmoidoscopy — every 10 years + FIT every year
- Colonoscopy screening — every 10 years
Other screening strategies may be used based on age, individual risk factors and personal choices. The key is to communicate with your doctor and ask questions about what colon cancer screening strategy is right for you.