Highlights
- The number of guaiac fecal occult blood tests (gFOBTs) performed in Ontario showed a plateauing trend in recent years (2009 to 2014).
- In 2014, 1.6 million or 40% of screen-eligible Ontarians were overdue for colorectal cancer screening, which suggests a continual need to improve participation in colorectal cancer screening using fecal-based tests.
- Transition to the fecal immunochemical test in ColonCancerCheck as the recommended screening test in the near future is expected to lead to increases in colorectal cancer screening participation.
An analysis of temporal trends in the number of guaiac fecal occult blood tests (gFOBTs) and colonoscopies performed reveals that colorectal cancer screening test volumes have stalled in Ontario. From 2009 to 2014, the number of gFOBTs performed in people ages 50 to 74 showed an overall plateauing trend, with fluctuations from year to year. The number of colonoscopies performed in people ages 50 to 74 also plateaued after 2008, but have been relatively steady in recent years (304,816 colonoscopies in 2011, 308,116 colonoscopies in 2014).
These plateaus are quite different from the relatively sharp increase in the number of gFOBTs performed in people ages 50 to 74 that occurred when ColonCancerCheck (CCC)—Ontario’s organized colorectal cancer screening program—was launched in 2008 (from 499,299 gFOBTs in 2007 to 649,366 gFOBTs in 2008). This increase can be attributed, in part, to the province-wide public awareness and education campaign efforts that accompanied CCC’s launch. It may have also helped slow the rise in the number of colonoscopies performed because more people were getting screened with gFOBT instead of ad hoc colonoscopy.
Plateauing trends in the number of gFOBTs performed suggest a continual need to improve participation in colorectal cancer screening. Approximately 1.6 million people in Ontario (about 40% of all screen-eligible Ontarians) were overdue for colorectal cancer screening in 2014. People are considered overdue for colorectal cancer screening if they:
- did not complete a gFOBT in the last 2 years; and
- did not have a colonoscopy in the last 10 years; and
- did not have a flexible sigmoidoscopy in the last 5 years.*
Colorectal cancer is the third most commonly diagnosed cancer in Ontario and has the second highest age-adjusted mortality rate for both sexes combined (22.9 deaths per 100,000 people).[1] Organized colorectal cancer screening can improve colorectal cancer outcomes and reduce colorectal cancer-specific mortality through early detection.[2] CCC recommends screening every 2 years with the gFOBT for people at average risk of developing colorectal cancer (men and women ages 50 to 74 without a family history of the disease).[3] Although the gFOBT is the recommended screening test, people sometimes get screened with colonoscopies in an opportunistic manner.
Cancer Care Ontario is planning to implement the fecal immunochemical test (FIT) in CCC as the recommended screening test for people at average risk of colorectal cancer. The FIT is a fecal-based test like the gFOBT, but it has a number of advantages, including easier sample collection and greater sensitivity for detecting colorectal cancer and advanced adenomas.[2] [4] Due to these advantages, FIT is expected to increase participation in colorectal cancer screening and produce higher cancer detection rates, leading to better health outcomes.