From the Guidelines
A patient undergoing colonoscopies every 10 years does not need to also have Fecal Immunochemical Tests (FIT) every 2 years, as colonoscopy is considered the gold standard for colorectal cancer screening and provides more comprehensive visualization of the entire colon. The American College of Physicians guidance statement suggests that clinicians should select the colorectal cancer screening test with the patient on the basis of a discussion of benefits, harms, costs, availability, frequency, and patient preferences 1. According to the guidance, suggested screening tests and intervals are fecal immunochemical testing or high-sensitivity guaiac-based fecal occult blood testing every 2 years, colonoscopy every 10 years, or flexible sigmoidoscopy every 10 years plus fecal immunochemical testing every 2 years 1. However, when a patient is already on a regular colonoscopy screening schedule, adding FIT testing would be redundant and does not provide additional benefit, as colonoscopy has higher sensitivity for detecting both cancer and precancerous lesions compared to FIT testing 1. Some key points to consider include:
- The effectiveness of colonoscopy has not been evaluated in RCTs, but it is associated with the best sensitivity for adenomas measuring at least 10 mm and has been widely used for CRC screening on the basis of observational and modeling data 1.
- FIT testing is associated with better sensitivity and specificity than gFOBT, and both tests need to be repeated, but test accuracy varies by type of FIT 1.
- The combination of flexible sigmoidoscopy with FIT is more beneficial than flexible sigmoidoscopy alone as a screening test, but this does not apply to patients already undergoing colonoscopy every 10 years 1. The U.S. Multi-Society Task Force on Colorectal Cancer also recommends colonoscopy every 10 years as a tier 1 test, and FIT as an alternative screening method for patients who cannot or choose not to undergo colonoscopy 1. Therefore, following one consistent screening method as recommended by your healthcare provider is the most effective approach, and routine dual screening with both methods is not standard practice.
From the Research
Colorectal Cancer Screening Recommendations
The U.S. Multi-Society Task Force on Colorectal Cancer recommends colonoscopy every 10 years and annual fecal immunochemical test (FIT) as the cornerstones of screening 2.
Screening Intervals for Average-Risk Individuals
For average-risk individuals, colonoscopy every 10 years and FIT annually are recommended as first-tier tests 2. Another study suggests that FIT can be performed every 1-2 years in average-risk individuals 3.
Combination of Colonoscopy and FIT
There is no direct evidence to suggest that a patient undergoing colonoscopies every 10 years should also have FIT every 2 years. However, the studies suggest that both colonoscopy and FIT are important screening tools for colorectal cancer, and the choice of screening modality depends on various factors, including patient preference and risk factors 2, 3, 4.
Importance of Screening Adherence
Adherence to screening recommendations is crucial for the early detection and prevention of colorectal cancer. Barriers to follow-up colonoscopies for patients with positive FIT results include patient-related, provider-related, and system-related factors 5.
Key Points to Consider
- Colonoscopy every 10 years and annual FIT are recommended as first-tier tests for average-risk individuals 2.
- FIT can be performed every 1-2 years in average-risk individuals 3.
- Both colonoscopy and FIT are important screening tools for colorectal cancer, and the choice of screening modality depends on various factors 2, 3, 4.
- Adherence to screening recommendations is crucial for the early detection and prevention of colorectal cancer 6, 5.