Faculty Bibliography

BACKGROUND:Emerging blood tests may improve colorectal cancer (CRC) screening uptake and outcomes but are less sensitive for advanced precancerous lesions than some currently recommended tests. We examine whether these tests meet expectations for U.S. Preventive Services Task Force (USPSTF) recommendation. METHODS:A decision-analytic model that informed USPSTF was replicated and used to estimate the lifetime benefits (averted CRC cases & deaths, life-years gained [LYG]), burdens (required screening tests & colonoscopies), and harms (colonoscopy-related complications) for annual, biennial or triennial blood testing through age 45-75 years vs a benchmark of recommended and contemporary stool-based strategies, with colonoscopy screening as the reference. Base-case analyses assumed 100% adherence. Sensitivity analyses evaluated more realistic scenarios. RESULTS:Among benchmark strategies, colonoscopy screening had the most benefit, with an estimated 30 CRC deaths averted, 356 LYG, 4270 colonoscopies required and 15 complications per 1000 adults; stool-based strategies resulted in 81-88% of LYG for colonoscopy, 6829-19,476 screening tests, 1523-1880 colonoscopies, and 9-10 complications. By comparison, annual blood testing resulted in 85-87% of LYG for colonoscopy and an intermediate number of screenings, colonoscopies and complications. Biennial and triennial blood testing provided 57-72% of LYG for colonoscopy but resulted in net population benefit under plausible scenarios for increased utilization vs existing strategies. CONCLUSIONS:The estimated benefits, burdens and harms of annual blood testing are within the range of current CRC screening strategies. Biennial and triennial testing should also be considered for recommendation given potential for increased utilization and net population benefit.

BACKGROUND:Measurement of colorectal polyps is typically performed via visual estimation, which is prone to bias. Studies have evaluated the accuracy of visual estimation and utility of assistive tools, but results have been mixed. This study aims to clarify the accuracy of visual estimation as a measurement tool, and the benefits of artificial intelligence. METHODS:MEDLINE and Embase were searched through October 2024. Extraction and quality assessment were performed independently by two authors. The primary outcome was the pooled absolute mean difference in size between visual estimation and control. Secondary outcomes included subgroup analysis of expert vs trainee status, accuracy of artificial intelligence, study origin (East vs. West), comparator type, definition of accuracy, polyp size, direction of estimation, and image type. RESULTS:35 studies with 42,964 polyp measurements were included in our analysis. All studies were of high quality and there was no evidence of publication bias. The pooled absolute mean difference from comparator was 1.68mm (CI 1.21-2.15) with high variability explained by differences in the comparator, the direction of estimation, image type, and size of the polyp. Overall accuracy was 60% with high variability as well, with increased accuracy with video displayed over photos. Artificial intelligence improved accuracy with an odds ratio of 7.46. CONCLUSION/CONCLUSIONS:Visual estimation is an inaccurate and imprecise way to measure colorectal polyps. Further research is needed to determine the impact on clinical outcomes related to colorectal cancer. Investment in new technology to aid in polyp measurement is an important next step.

BACKGROUND AND AIMS/OBJECTIVE:There is limited information regarding performance of fecal immunochemical test (FIT) in post-polypectomy surveillance, or for screening individuals with a family history of CRC . We conducted a systematic review to assess current evidence regarding diagnostic performance of one time FIT in increased risk populations. METHODS:A comprehensive search of multiple databases was conducted to assess studies reporting performance of a one-time FIT as screening or surveillance tool in individuals at increased risk of CRC. RESULTS:We identified three studies reporting on 8817 individuals with personal history of polyps who underwent FIT testing. For CRC detection, one time FIT showed sensitivity ranging from 27.6% to 100.0% and specificity ranging from 55.9% to 94.1% with variable test thresholds and index polyp histology. We identified 12 studies reporting on 5525 individuals with family history of CRC. One time FIT showed a sensitivity ranging from 25.0% to 100.0% and specificity ranging from 83.1% to 92.0% , with variable test thresholds and family history characteristics. CONCLUSION/CONCLUSIONS:Current evidence is limited to adequately assess diagnostic performance of FIT in individuals with family history of CRC, or as follow up after polypectomy.

BACKGROUND/UNASSIGNED:Several patient and tumor characteristics impact the prognosis of non-metastatic colon cancer. Among those, tumor location is believed to be a significant factor, as proximal lesions are associated with lower overall survival (OS) in modern cohorts. We aimed to validate these findings in a cohort of patients from the Minnesota Colon Cancer Control Study who underwent curative colectomy. METHODS/UNASSIGNED:From 1976 to 1992, 46,551 patients aged 50-80 years were randomized to usual care, annual, or biennial screening with fecal occult blood testing (FOBT). Positive FOBT was followed by colonoscopy. We analyzed participants whose colonoscopy revealed colon adenocarcinoma to estimate the impact of tumor laterality on survival after adjustment for demographic and clinicopathologic characteristics. Proximal tumors were defined as those between the cecum and the splenic flexure. RESULTS/UNASSIGNED:Of 1,486 patients, 796 met inclusion criteria; 57% had proximal cancers. After adjustment, there was no significant difference between proximal and distal tumors in disease-specific mortality [subdistribution hazard ratio (SHR) =0.94, 95% confidence interval (CI): 0.70-1.3], but proximal tumors had lower rates of death from any cause [hazard ratio (HR) =0.9, 95% CI: 0.77-1.00]. CONCLUSIONS/UNASSIGNED:Although lacking granular data, these findings from the pre-modern chemotherapy era raise questions about the generalizability of the association between side of origin and prognosis identified in contemporary, treatment-based trials.

Description Colorectal cancer (CRC) is a leading cause of morbidity and cancer-related mortality in the US. Despite multiple screening options, adherence to CRC screening in the US remains suboptimal and there are racial, ethnic and geographic disparities in CRC screening rates and outcomes. Advances in diagnostic technology have allowed for development and validation of blood tests for CRC screening. In this clinical practice update, our aims were to review the current evidence on blood tests, and the potential implications for CRC screening. We leveraged published modelling studies to understand the optimal test performance characteristics, interval, and uptake that would be needed for blood tests to achieve comparable effectiveness to that of currently available stool tests and screening colonoscopy.

With nearly 60 million Americans aged 65 and older, gastrointestinal (GI) conditions are a leading cause of healthcare utilization in this population. Despite this, older adults remain underrepresented in GI clinical trials and research, limiting evidence-based care. This review highlights three pivotal studies addressing this gap: (1) proton pump inhibitors, which are commonly used to treat gastroesophageal reflux disease, are not associated with the later development of dementia; (2) undertreatment of chronic inflammation among older adults with inflammatory bowel disease is associated with a higher rate of adverse events compared to treatment with anti-TNF therapy, a biologic agent; (3) the majority (85%) of surveillance colonoscopies among older adults with a life expectancy of ≥ 10 years did not yield colorectal cancer, advanced dysplasia, or ≥ 3 polyps.

OBJECTIVES/OBJECTIVE:Post-colonoscopy colorectal cancer (PCCRC) represents an important real-world colonoscopy quality indicator. Using a national database, we evaluated predictors of PCCRC in fecal immunochemical test (FIT)-positive individuals, determined the PCCRC 3-year rate (PCCRC-3y), and performed a root cause analysis (RCA). METHODS:This retrospective cohort study evaluated FIT-positive patients who underwent colonoscopy from January 2015 to July 2022. Data was collected from the Veterans Affairs (VA) national database. PCCRC was defined as CRC detected ≥6 months after colonoscopy. CRC was identified using SNOMED codes and the VA Cancer Registry. The World Endoscopy Organization methodology was used to perform the RCA and calculate the PCCRC-3y rate. RESULTS:We identified 132 PCCRCs among 52,167 FIT-positive individuals. The PCCRC-3y rate was 6.4% (95% CI, 5.0-7.7%). PCCRC locations were proximal colon (43.2%), distal colon (34.8%), and rectum (22%). Root causes were likely new CRC (17.4%), missed lesions with adequate (31.2%) or inadequate (9.8%) examination, incomplete polyp resection (22%), and detected but unresected lesions (19.7%). 16.7% of patients with PCCRC had poor bowel preparation on index colonoscopy. The cecal intubation rate was 88.6% and rectal retroflexion rate was 84.5%. In 14.4% of cases, recommended surveillance intervals did not adhere to established guidelines. Independent predictors of PCCRC were ages 70-79 (HR 7.86; 95% CI, 1.08-57.39), age ≥80 (HR 10.18; 95% CI, 1.06-97.98), tubulovillous adenoma (HR 3.98; 95% CI, 2.52-6.29), and adenoma with high-grade dysplasia (HR 10.15; 95% CI, 5.91-17.42). CONCLUSIONS:Among FIT-positive individuals, the PCCRC-3y rate was 6.4%, with missed lesions and incomplete resection as key contributors. These findings provide useful information on quality metrics in FIT-based CRC screening programs.

IMPORTANCE/UNASSIGNED:Colorectal cancer screening is widely recommended but underused. Blood-based screening offers the potential for higher adherence compared with endoscopy or stool-based testing but must first be clinically validated in a screening population. OBJECTIVE/UNASSIGNED:To evaluate the clinical performance of an investigational blood-based circulating tumor DNA test for colorectal cancer detection in an average-risk population using colonoscopy with histopathology as the reference method. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:Prospective, multicenter, cross-sectional observational study enrolling participants between May 2020 and April 2022 who were asymptomatic adults aged 45 to 85 years, at average risk of colorectal cancer, and willing to undergo a standard-of-care screening colonoscopy. Participants, staff, and pathologists were blinded to blood test results, and laboratory testing was performed blinded to colonoscopy findings. The study was conducted at 201 centers across 49 US states and the United Arab Emirates. Site-based and mobile phlebotomy were used for blood collection. EXPOSURES/UNASSIGNED:Participants were required to complete a screening colonoscopy after blood collection. MAIN OUTCOMES AND MEASURES/UNASSIGNED:The primary end points were sensitivity for colorectal cancer, specificity for advanced colorectal neoplasia (colorectal cancer or advanced precancerous lesions), negative predictive value for advanced colorectal neoplasia, and positive predictive value for advanced colorectal neoplasia. The secondary end point was sensitivity for advanced precancerous lesions. RESULTS/UNASSIGNED:The median age of participants in the evaluable cohort (n = 27 010) was 57.0 years, and 55.8% were women. Sensitivity for colorectal cancer was 79.2% (57/72; 95% CI, 68.4%-86.9%) and specificity for advanced colorectal neoplasia was 91.5% (22 306/24 371; 95% CI, 91.2%-91.9%). The negative predictive value for advanced colorectal neoplasia was 90.8% (22 306/24 567; 95% CI, 90.7%-90.9%) and the positive predictive value for advanced colorectal neoplasia was 15.5% (378/2443; 95% CI, 14.2%-16.8%). All primary end points met prespecified acceptance criteria. The sensitivity for advanced precancerous lesions was 12.5% (321/2567; 95% CI, 11.3%-13.8%), which did not meet the prespecified acceptance criterion. CONCLUSIONS AND RELEVANCE/UNASSIGNED:In an average-risk colorectal cancer screening population, a blood-based test demonstrated acceptable accuracy for colorectal cancer detection, but detection of advanced precancerous lesions remains a challenge, and ongoing efforts are needed to improve test sensitivity. TRIAL REGISTRATION/UNASSIGNED:ClinicalTrials.gov Identifier: NCT04369053.

BACKGROUND:Sarcopenia has been associated with adverse postoperative outcomes in older age cohorts, but has not been assessed in older adults with inflammatory bowel disease (IBD). Further, current assessments of sarcopenia among all aged individuals with IBD have used various measures of muscle mass as well as cutoffs to define its presence, leading to heterogeneous findings. METHODS:In this single-institution, multihospital retrospective study, we identified all patients aged 60 years and older with IBD who underwent disease-related intestinal resection between 2012 and 2022. Skeletal Muscle Index (SMI) and Total Psoas Index (TPI) were measured at the superior L3 endplate on preoperative computed tomography scans and compared through receiver operating characteristic curve. We then performed multivariable logistic regression to assess risk factors associated with an adverse 30-day postoperative outcome. Our primary outcome included a 30-day composite of postoperative mortality and complications, including infection, bleeding, cardiac event, cerebrovascular accident, acute kidney injury, venous thromboembolism, reoperation, all-cause rehospitalization, and need for intensive care unit-level care. RESULTS:A total of 120 individuals were included. Overall, 52% were female, 40% had ulcerative colitis, 60% had Crohn's disease, and median age at time of surgery was 70 years (interquartile range: 65-75). Forty percent of older adults had an adverse 30-day postoperative outcome, including infection (23%), readmission (17%), acute kidney injury (13%), bleeding (13%), intensive care unit admission (10%), cardiac event (8%), venous thromboembolism (7%), reoperation (6%), mortality (5%), and cerebrovascular accident (2%). When evaluating the predictive performance of SMI vs TPI for an adverse 30-day postoperative event, SMI had a significantly higher area under the curve of 0.66 (95% CI, 0.56-0.76) as compared to 0.58 (95% CI, 0.48-0.69) for TPI (P = .02). On multivariable logistic regression, prior IBD-related surgery (adjusted odds ratio [adjOR] 6.46, 95% CI, 1.85-22.51) and preoperative sepsis (adjOR 5.74, 95% CI, 1.36-24.17) significantly increased the odds of adverse postoperative outcomes, whereas increasing SMI was associated with a decreased risk of an adverse postoperative outcome (adjOR 0.88, 95% CI, 0.82-0.94). CONCLUSIONS:Sarcopenia, as measured by SMI, is associated with an increased risk of postoperative complications among older adults with IBD. Measurement of SMI from preoperative imaging can help risk stratify older adults with IBD undergoing intestinal resection.