From the Guidelines
The current recommendation is to begin regular colorectal cancer screening at age 45 for people at average risk. The preferred screening options include a colonoscopy every 10 years, a stool-based FIT (fecal immunochemical test) annually, a stool DNA test (like Cologuard) every 3 years, or a CT colonography (virtual colonoscopy) every 5 years 1. For colonoscopy preparation, you'll need to follow a clear liquid diet the day before, take prescribed bowel-cleansing medication (such as GoLYTELY, MoviPrep, or SUPREP), and arrange for someone to drive you home after the procedure due to sedation effects. These recommendations were lowered from age 50 to 45 in recent years due to increasing rates of colorectal cancer in younger adults, as supported by the American Cancer Society's updated guideline in 2018 1. Early screening is crucial because colorectal cancer often develops slowly from precancerous polyps, which can be removed during colonoscopy before becoming cancerous. People with higher risk factors, such as a family history of colorectal cancer or certain genetic conditions, may need to start screening earlier or have more frequent tests.
Some key points to consider when screening for colorectal cancer include:
- The American College of Physicians recommends offering CRC screening beginning at age 50 years, but also suggests that sequential offers of screening tests and risk-stratified screening are reasonable approaches 1.
- The U.S. Preventive Services Task Force recommends screening for colorectal cancer in adults aged 50 to 75 years, with the decision to screen in adults aged 76 to 85 years being an individual one 1.
- The American College of Gastroenterology suggests screening in average-risk persons aged 45 to 49 years and recommends screening average-risk persons aged 50 to 75 years 1.
However, the most recent and highest quality study, which is the 2018 American Cancer Society guideline, recommends starting screening at age 45 for average-risk adults 1. Therefore, starting screening at age 45 is the most recommended approach, considering the increasing incidence of colorectal cancer in younger adults.
From the Research
Current Screening Recommendations for Colon Cancer at 45
- The current United States guidelines present a panel of options that include colonoscopy and stool testing with the fecal immunochemical test (FIT) for colorectal cancer screening 2.
- There is no debate around the effectiveness of colorectal cancer screening in reducing disease burden, but the most effective and cost-effective screening modality is still being researched 2.
- A systematic review and meta-analysis found that FIT may be similar to 1-time colonoscopy in the detection rate of CRC, although it has lower detection rates of any adenoma and advanced adenoma than 1-time colonoscopy 3.
- The same study found that annual or biennial FIT appears to be very cost-effective or cost-saving compared with colonoscopy every 10 years 3.
- Another study found that sensitivity for advanced neoplasia was modest and did not increase when using two samples instead of one, and FIT predominantly detected adenomas with pedunculated shape and high-risk dysplasia 4.
- A large, pragmatic, multicenter, randomized, parallel group trial is being conducted to compare screening with colonoscopy vs. the annual fecal immunochemical test (FIT) in 50,000 average risk individuals 5.
- The fecal immunochemical test (FIT) is a tool used for colorectal cancer screening and its use is growing rapidly, with several advantages including ability to screen using only 1 stool sample per cycle 6.
Screening Modalities
- Colonoscopy: a commonly used modality for colorectal cancer screening, with high detection rates for colorectal neoplasia 2, 3.
- Fecal Immunochemical Test (FIT): a stool test used for colorectal cancer screening, with advantages including ability to screen using only 1 stool sample per cycle 3, 6.
- Stool testing: a non-invasive screening modality that can be used as an alternative to colonoscopy 2.