Colorectal Cancer Screening Follow-Up

Measure	Desired Direction	As of this Report
6-month follow-up: Percentage of Ontario screen-eligible people, aged 50 to 74, with an abnormal FOBT result who underwent colonoscopy within 6 months of the abnormal screen date
8-week follow-up: Percentage of Ontario screen-eligible people, aged 50 to 74, with an abnormal FOBT result who underwent colonoscopy within 8 weeks of the abnormal screen date
See Methodology and Approach to find out how the ratings are calculated.

Key findings

In 2015, approximately 20,000 Ontarians aged 50 to 74 had an abnormal FOBT result that required follow-up with colonoscopy. Of these people, 15,800 (78%) had a colonoscopy within 6 months of their abnormal FOBT result, compared to 76% in 2012. Notable variations were present by region. Also in 2015, over 8,800 Ontarians (44%) who had an abnormal FOBT result had a follow-up colonoscopy within 8 weeks, compared to 42% in 2012. However, performance for this indicator decreased slightly from 2014 (46%) to 2015 (44%).

What is colorectal cancer screening (FOBT)?

• A screening test identifies people in a healthy, asymptomatic population who may be at risk for disease. It is not a diagnostic test. The purpose of colorectal cancer screening with FOBT is to find pre-cancerous changes or cancer at an early stage, when it is easier to treat. Ontario operates organized, population-based screening programs for 3 types of cancer: breast, cervical and colorectal.
• Different types of colorectal cancer screening tests exist, ranging from at-home tests (such as the FOBT) to visual inspection of the colon (such as colonoscopy or flexible sigmoidoscopy).
• ColonCancerCheck (Ontario’s population-based colorectal cancer screening program) recommends that people aged 50 to 74 without a family history of colorectal cancer (i.e. those at average risk) get screened every 2 years with an FOBT, followed by colonoscopy if their FOBT is abnormal¹.
• ColonCancerCheck recommends that people at increased risk of colorectal cancer due to a family history in a first-degree relative (i.e. they have a parent, sibling or child who has been diagnosed with the disease) screen with colonoscopy beginning at age 50, or 10 years earlier than the age at which their relative was diagnosed, whichever occurs first¹.
• The FOBT can find very small amounts of blood in someone’s stool that may be caused by cancer in the colon or rectum, even when they don’t feel any symptoms².
• An abnormal FOBT does not necessarily mean that someone has cancer, but additional testing with a colonoscopy is needed to find out why there is blood in their stool. During colonoscopy, cancer may be found. Polyps (pre-cancerous lesions) may also be removed during colonoscopy.
• Colorectal cancer screening has been shown to reduce deaths from colorectal cancer³.
• Cancer Care Ontario monitors 2 indicators related to the follow up of abnormal results for colorectal cancer screening: the percentage of people who receive a follow-up colonoscopy within 6 months of an abnormal fecal occult blood test (FOBT) (an indicator of the overall compliance with follow-up colonoscopy) and the percentage of people who receive a follow-up colonoscopy within 8 weeks of an abnormal FOBT (an indicator of the timeliness of follow up).

What do the results show?

Colonoscopy follow-up within 6 months has levelled off (Figure 1).

• In 2015, 78% (15,766) of Ontarians who had an abnormal FOBT result had a colonoscopy within 6 months, which is similar to the 6-month follow-up in 2014 (77%).
• In 2015, the Local Health Integration Network (LHIN) with the highest 6-month follow-up was Hamilton Niagara Haldimand Brant (83%).
• The LHIN with the lowest 6-month follow-up in the same year was Toronto Central (69%).
• The LHIN with the greatest improvement in 6-month follow-up from 2014 to 2015 was North East, rising from 76% in 2014 to 82% in 2015, which is an increase of 6 percentage points.
• The LHIN with the greatest decrease in 6-month follow-up during the same time period was North West, dropping from 82% in 2014 to 77% in 2015, which is a decrease of 5 percentage points.

Follow-up of abnormal FOBT results within 6 months varies by demographic factor.

• Variation was present in 6-month follow-up by age group in 2015 (Figure 2). The percentage of people receiving a colonoscopy within 6 months of an abnormal FOBT result was highest at 81% in people aged 50 to 54 (the youngest age group) and lowest at 75% in people aged 70 to 74 (the oldest age group). A similar pattern can be seen in previous years.
• Men were more likely than women to receive a colonoscopy within 6 months of an abnormal FOBT result in 2015 (79% of men vs. 78% of women, p=0.008).

The percentage of Ontarians receiving follow-up colonoscopies within 8 weeks of an abnormal FOBT has decreased, although there is notable variation by region (Figure 3).

• Cancer Care Ontario recommends that Ontarians who have an abnormal FOBT result receive a colonoscopy within 8 weeks of that result⁵. This measure is an indicator of the timeliness of follow up.
• In 2015, over 8,800 Ontarians had a follow-up colonoscopy within 8 weeks of an abnormal FOBT result (44%), compared to 46% in 2014.
• In 2015, the LHIN with the best colonoscopy wait-time performance (colonoscopy within 8 weeks of an abnormal FOBT result) was Central West (48%).
• The Toronto Central, South East and North West LHINs had the lowest percentage of colonoscopies performed within 8 weeks of an abnormal FOBT result (38%).
• The Waterloo Wellington LHIN had the greatest change in performance for this indicator, dropping from 52% in 2014 to 47% in 2015, which is a decrease of 5 percentage points.
• In 2014, Cancer Care Ontario implemented the Gastrointestinal Endoscopy Quality-Based Procedure (QBP) as part of Ontario’s health system funding reform. As a result, changes to the colonoscopy funding structure may have impacted 8-week follow-up performance. ColonCancerCheck is working with the regions to reverse this trend.

Follow up within the recommended 8 weeks varies by socio-demographic factor.

• Similar to the 6-month follow-up indicator, the percentage of people receiving a colonoscopy within 8 weeks of an abnormal FOBT result was highest at 47% in people aged 50 to 54 (the youngest age group) and lowest at 42% in people aged 65 to 74 (the oldest age group). A similar pattern can be seen in previous years.
• Men were more likely than women to have a colonoscopy within 8 weeks of an abnormal FOBT result in 2015 (45% vs. 43%, p<0.001).

Why is this important to Ontarians?

• While FOBT identifies people at risk of having colorectal cancer, colonoscopy is required to make a definitive diagnosis. This means that people with an abnormal FOBT result should have a follow-up colonoscopy to realize the benefits of screening with FOBT. A recent meta-analysis showed that deaths from colorectal cancer in people aged 50 and over can be reduced by 13% when they get screened regularly (annually or every other year) with an FOBT, followed by a colonoscopy if their FOBT is abnormal³.
• Cancer Care Ontario has explored reasons people may not have a colonoscopy after an abnormal FOBT. While a variety of factors (including personal preference and contraindications, i.e. symptoms or conditions that might prevent someone from having a procedure) may contribute, system factors also play a role. Follow up after an abnormal FOBT occurs less often when:
  • an FOBT is repeated rather than performing a colonoscopy; and
  • the FOBT was done soon after a colonoscopy⁴.
• The Canadian Association of Gastroenterology (CAG) published a Canadian consensus on medically acceptable wait times in 2006, which included a recommendation that follow-up colonoscopy should be completed within 2 months of an abnormal FOBT^5,6. ColonCancerCheck has adopted an 8-week benchmark based on the CAG consensus.
• Measuring follow up helps the ColonCancerCheck program monitor access to colorectal screening and ensures that program participants have timely follow up.

Next steps

• To identify strategies to improve follow up, Cancer Care Ontario continues to evaluate the reasons physicians fail to send people with abnormal FOBT results for follow-up colonoscopy and the reasons patients fail to comply with follow-up recommendations.
• Cancer Care Ontario, with funding from the Ontario Institute for Cancer Research, is currently conducting a pilot to explore the use of navigation to improve overall follow up, as well as the timeliness of follow up with colonoscopy, in people with an abnormal FOBT result.
• Cancer Care Ontario has developed an online Primary Care Screening Activity Report (PC SAR) for all 3 screening programs (cervical, breast and colorectal cancer). This tool (accessed online) allows physicians in patient enrolment model practices to see the complete screening status of each of their enrolled age-eligible patients, including those due for screening and follow up. Next steps include working with Cancer Care Ontario’s Regional Primary Care Leads to identify barriers to adoption of the tool, and to promote and encourage use of the PC SAR.

View Notes

1. Cancer Care Ontario [Internet]. Toronto: Cancer Care Ontario. About ColonCancerCheck; 2015 Jul 16 [cited 2015 Dec 18]. Available from: https://cancercare.on.ca/pcs/screening/coloscreening/cccworks/.
2. Greegor DH. Diagnosis of large-bowel cancer in the asymptomatic patient. JAMA.1967; 201:943–5.
3. Tinmouth J, Vella E, Baxter NN, Dubé C, Gould M, Hey A, et al. Colorectal cancer screening in average risk populations: evidence summary. Toronto: Cancer Care Ontario; 2015.
4. Correia A, Rabeneck L, Baxter NN, Paszat LF, Stradhar R, Yun L, Tinmouth J. Lack of follow-up colonoscopy after positive FOBT in an organized colorectal cancer screening program is associated with modifiable health care practices. Prev Med. 2015 Jul; 76:115­–22.
5. Paterson WG, Depew WT, Paré P, Petrunia D, Switzer C, Veldhuyzen van Zanten SJ, et al. Canadian consensus on medically acceptable wait times for digestive health care. Can J Gastroenterol. 2006 Jun; 20(6):411–23.
6. Canadian Partnership Against Cancer. Quality determinants and indicators for measuring colorectal cancer screening program performance in Canada. Toronto: The Partnership; 2012.