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ColonCancerCheck

Research

• What are the key findings outlined by the FOBT Standards?
• How were FOBT standards developed?
• What is the positivity rate using biennial FOBT screening?
• Many physicians are skeptical about the claim that FOBT is the only method of colorectal cancer screening that has been proven in randomized controlled trials (RCTs) to reduce mortality from colorectal cancer. Colonoscopies reduce deaths by detecting cancerous polyps early and by removing pre-cancerous polyps. Hasn't this been proven?
• What do the new colonoscopy standards cover?
• How and why were the colonoscopy standards developed?
• Will the program develop standards/guidelines for colonoscopy surveillance?

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What are the key findings outlined by the FOBT Standards?

These evidence-based standards focus on three areas: performance, kit standards and usability and laboratory standards:

Performance Highlights

• Use one brand of FOBT kit to reduce variability in performance
• Develop a process to regularly monitor the FOBT performance of participating laboratories

Kit Standards and Usability Highlights

• No dietary or medication restrictions except citrus fruit and juices and vitamin C supplements before and during the collection of stool samples
• Design a customized kit and package insert that includes :
• easy-to-read, understandable kit instructions
•  time and date of sample collection on the kit
• a leak-proof envelope to protect sample during mailing, particularly in extreme temperatures
• an outer envelope with easy-to-mail-back features such as the laboratory address and pre-paid postage

Lab Standards Highlights

• A positive test has one or more positive windows on the test card
• Participating labs must meet Ontario Laboratory Accreditation requirements and have internal and external quality control programs for FOBT testing

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How were the FOBT standards developed?

The standards were developed by an expert panel supported by Cancer Care Ontario's Program in Evidence-Based Care (PEBC). The FOBT standards are based on published literature, information obtained from other colorectal cancer screening programs, unindexed literature on the Web and kit manufacturers' instructions.

• Guaiac Fecal Occult Blood Test (FOBT) Laboratory Standards [PDF]

What is the positivity rate using biennial FOBT screening?

During the first 2 years of the CC program, the FOBT positivity rate has been approximately 4%.  Many individuals with a positive FOBT will be found to have pre-cancerous colorectal polyps at colonoscopy. These polyps will be removed during the colonoscopy. FOBT's sensitivity to detect cancer in repeated testing every one to two years is 46%.

Many physicians are skeptical about the claim that FOBT is the only method of colorectal cancer screening that has been proven in randomized controlled trials (RCTs) to reduce mortality from colorectal cancer. Colonoscopies reduce deaths by detecting cancerous polyps early and by removing pre-cancerous polyps. Hasn't this been proven?

The scientific evidence is strongest to support FOBT (Level A)*. Three landmark randomized controlled trials have shown a reduction in colorectal cancer deaths of 16% with FOBT screening combined with colonoscopy for those with a positive FOBT. There are no randomized controlled trials that have evaluated colonoscopy. The evidence for colonoscopy is Level C for those at average risk. So, although colonoscopy is considered the gold-standard test by many, no direct evidence for its use as a screening modality currently exists.

• The Canadian Task Force on Preventive Health Care defines Level A evidence as good evidence to recommend the clinical preventive action. Level C rating means existing evidence is conflicting and does not allow making a recommendation for or against the use of the clinical preventive action, however other factors may influence decision-making.

What do the new colonoscopy standards cover?

The colonoscopy standards cover three key aspects of colonoscopy: physicians, hospitals and performance. Physician standards outline required experience and training and state that to maintain competency, physicians need to perform a minimum of 200 colonoscopies annually going forward. Hospital standards deal with patient assessment, infection control, monitoring during and after administration of sedation and emergency resuscitation capacity. Performance standards provide detail around acceptable rates of completion and complications and deals with issues such as equipment, perforation rates, sedation, bowel preparation and pathology.

• Cancer Care Ontario Colonoscopy Standards [PDF]

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How were the colonoscopy standards developed?

The standards were developed by an exoert panel supported by Cancer Care Ontario's Program in Evidence-Based Care (PEBC). The colonoscopy standards are based on published literature and input from practice leaders, and scientists. The comprehensiveness of these standards makes them the first of their kind in Canada.

Will the program develop standards/guidelines for colonoscopy surveillance?

To complement the colonoscopy standards, ColonCancerCheck adopted colonoscopy surveillance guidelines outlined in “Guidelines for Colonoscopy Surveillance After Polypectomy: A Consensus Update by the U.S. Multi-Society Task Force on Colorectal Cancer and the American Cancer Society" that were published in Gastroenterology in 2006.

• Colonoscopy Surveillance Guidelines [PDF]

 

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