Colorectal Cancer Screening Guidelines

Screening Recommendations

The Canadian Task Force on Preventive Health Care recommends fecal occult blood testing (either guaiac-based or FIT) every 2 years for average-risk adults aged 50-74 years, and does not recommend colonoscopy as a primary screening test in Canada 1, 2
Start screening at age 50 for average-risk individuals 1, 2
Stop screening at age 75 - do not screen individuals 75 years or older 1, 2
The Canadian approach differs significantly from U.S. guidelines in two key ways: screening interval and colonoscopy recommendation 1, 2, 3

Screening interval: Every 2 years (not annually as recommended in the U.S.) 1, 2, 3
Colonoscopy is NOT recommended as a primary screening test in Canada, largely due to limited access and resource constraints 1, 3
When FIT is used, quantitative tests are preferred over qualitative tests 4, 5
Lower threshold cut-offs (20 μg/g or lower) are favored to define a positive test 4, 5

When FIT is positive, colonoscopy is the mandatory next step 4, 5
Delays beyond 6 months after positive FIT significantly increase risk: adjusted OR 1.31 for any colorectal cancer and 2.09 for advanced stage disease 6

U.S. guidelines now recommend starting at age 45, while Canada maintains age 50 1, 2
U.S. recommends annual FIT, while Canada recommends biennial testing 1, 2, 3
U.S. includes colonoscopy as a tier 1 screening option, while Canada does not recommend it as a primary screening test 1, 2

Do not perform upper gastrointestinal evaluation for a positive FIT with negative colonoscopy in the absence of upper GI symptoms 4, 5
Do not use dietary restrictions - patients should be explicitly instructed they do not need to adjust diet or medications to complete FIT 5
Do not use digital rectal exam samples - FIT programs should rely on spontaneously passed stool specimens 5
System barriers are the primary cause of non-adherence, including failure to arrange colonoscopy, failure to inform patients of positive results, and inadequate patient contact 6