Abstract
Adenomatous polyps are a common precursor lesion for colorectal cancer. ColonFlag is a machine- learning-based algorithm that uses basic patient information and complete blood cell counts (CBC) to identify individuals at elevated risk of colorectal cancer for intensified screening. The purpose of this study was to determine whether ColonFlag is also able to predict the presence of high risk adenomatous polyps at colonoscopy. This study was conducted at a large colon cancer screening center in Calgary, Alberta. The study population included asymptomatic individuals between the ages of 50 and 75 who underwent a screening colonoscopy between January 2013 and June 2015. All subjects had at least one CBC result within the year prior to colonoscopy. Based on age, sex, red blood cell parameters, inflammatory cells and platelets, the ColonFlag algorithm generated a score from 0 to 100. We compared the ability of the ColonFlag test result to discriminate between individuals who were found to have a high risk polyp and those with a normal colonoscopy. Among the 17,676 individuals who underwent a screening colonoscopy there were 1,014 found to have a high risk precancerous lesion (5.7%) and 60 were found to have colorectal cancer (0.3%). At a specificity of 95%, the odds ratio for a positive ColonFlag was 2.0 for those with an advanced precancerous lesion compared with those with a normal colonoscopy. The odds ratio did not vary according to patient subgroup, colorectal cancer location or stage. ColonFlag is a passive test that can use routine blood test results to help identify individuals at elevated risk for high risk precancerous polyps as well as frank colorectal cancer. These individuals may be targeted in an effort to achieve greater compliance with conventional screening tests.
Highlights
Population-based screening programs for colorectal cancer have been established in many countries.[1,2,3] The dual goals of screening are to reduce the incidence or colorectal cancer and subsequent mortality
We have described the development and validation of the ColonFlag score, an algorithm that incorporates patient factors with complete blood count information (CBC) and which is used to predict the presence of colorectal cancer at the time of testing.[6,7,8]
The majority of the individuals were at average risk for colorectal cancer; 9.1% of all potentially eligible individuals were considered to be at higher than average risk because of a previous history of polyps and 21.5% were considered to be at higher risk because of a family history of colorectal cancer (Table 1)
Summary
Population-based screening programs for colorectal cancer have been established in many countries.[1,2,3] The dual goals of screening are to reduce the incidence or colorectal cancer and subsequent mortality. To achieve these goals, a screening test must detect both high risk precancerous lesions (advanced adenomatous and sessile serrated polyps) and early invasive cancers. Despite the established benefits and the cost-effectiveness of screening for colorectal cancer, the uptake of screening is suboptimal.[4, 5] Colorectal cancer screening requires active participation of the individual by collecting a stool sample and/or undergoing a more invasive test, such as a colonoscopy. Screening could be enhanced through the use of a passive test that uses electronic medical records to identify individuals at elevated risk of harboring an asymptomatic colorectal cancer or a high risk precancerous lesion
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
