Strategies for Colorectal Cancer Screening

The incidence of colorectal cancer (CRC) is increasing worldwide. CRC has high mortality when detected at advanced stages, yet it is also highly preventable. Given the difficulties in implementing major lifestyle changes or widespread primary prevention strategies to decrease CRC risk, screening is the most powerful public health tool to reduce mortality. Screening methods are effective but have limitations. Furthermore, many screen-eligible persons remain unscreened. We discuss established and emerging screening methods, and potential strategies to address current limitations in CRC screening. A quantum step in CRC prevention might come with the development of new screening strategies, but great gains can be made by deploying the available CRC screening modalities in ways that optimize outcomes while making judicious use of resources

Helicobacter pylori test-and-treat intervention compared to usual care in primary care patients with suspected peptic ulcer disease in the United States

The Helicobacter pylori ( H. pylori ) “test-and-treat” strategy in uninvestigated dyspepsia is an effective alternative to prompt endoscopy. Our aims were to determine whether the combination of an educational session and availability of office-based H. pylori testing (test-and-treat intervention [TTI]) increases use of the test-and-treat strategy by primary care practitioners and whether it improves patient outcomes. Methods : We conducted a 1-yr prospective trial of patients with suspected peptic ulcer disease in six primary care centers, three with TTI and three designated as usual care controls (UCC). Results : H. pylori testing was performed in 81% of 54 TTI patients and in 49% of 39 UCC patients ( p = 0.004). TTI and UCC patients had similar gastroenterology referral rates (24% vs 33%, p = 0.33), endoscopy or upper GI radiography rates (30% vs 31%, p = 0.91), and primary care visits per patient (3.1 ± 2.8 vs 3.1 ± 2.6, p = 0.92). TTI patients were less likely than UCC patients to receive repeated antisecretory medication prescriptions (35% vs 66%, p = 0.003). Symptomatic status at 1 yr and satisfaction with medical care did not differ between groups. Median (and interquartile range) annualized disease-related expenditures per patient were $454 ($162–932) for TTI and $576 ($327–1435) for UCC patients ( p = 0.17). Conclusions : The combination of an educational session and availability of office-based H. pylori testing may increase acceptance of the test-and-treat strategy by primary care providers. It remains to be determined whether increased use of the test-and-treat strategy yields significant improvements in clinical and economic outcomes compared to usual care.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74830/1/j.1572-0241.2002.07118.x.pd

Rates and Predictors of Colorectal Cancer Screening

Introduction: Despite widespread recommendations for colorectal cancer screening, the U.S. screening rate is low. The objectives of this study were to describe the rates and predictors of colorectal cancer screening use by examining groups in two categories — 1) those who have ever been screened and 2) those with up-to-date screening — and to assess whether trends and predictors change over time. Methods: We analyzed data from the 2000 and 2003 National Health Interview Surveys about the use of fecal occult blood tests, sigmoidoscopies, and colonoscopies for adults aged 50 years and older and without a history of colorectal cancer (N = 11,574 in 2000 and N = 11,779 in 2003). Results: Rates in the 2000 study population of those who have ever been screened for colorectal cancer (53%) had increased in the 2003 study population (55%) as had the rates in the 2003 study population of those with up-to-date colorectal screening (53%) compared with the rates in the 2000 study population (38%). Among those who were ever screened, 76% were up-to-date with screening in 2003, compared with 68% in 2000. There was increased use of colonoscopies but decreased use of fecal occult blood tests and sigmoidoscopies. Individuals were more likely to be up-to-date with screening if they had higher income, higher education, insurance coverage, a usual source of care, and a dental visit in the last year than if these predictors were not evident. Since 2000, these predictors of colorectal cancer screening use have remained stable. Conclusion: Although there has been relatively limited success in increasing overall screening, it is encouraging that most people in the group of those who have ever been screened are up-to-date with colorectal cancer screening. Predictors for colorectal screening were stable over time despite changes in screening policies and rates. Further research is needed to uncover barriers to colorectal cancer screening

Prevalence and Clinical Features of Sessile Serrated Polyps: A Systematic Review

Background & Aims: Sessile serrated polyps (SSPs) could account for a substantial proportion of colorectal cancers. We aimed to increase clarity on SSP prevalence and clinical features. Methods: We performed a systematic review of MEDLINE, Web of Science, Embase, and Cochrane databases for original studies published in English since 2000. We included studies of different populations (United States general or similar), interventions (colonoscopy, autopsy), comparisons (world regions, alternative polyp definitions, adenoma), outcomes (prevalence, clinical features), and study designs (cross-sectional). Random-effects regression was used for meta-analysis where possible. Results: We identified 74 relevant colonoscopy studies. SSP prevalence varied by world region, from 2.6% in Asia (95% confidence interval [CI], 0–5.9) to 10.5% in Australia (95% CI, 2.8–18.2). Prevalence values did not differ significantly between the United States and Europe (P = .51); the pooled prevalence was 4.6% (95% CI, 3.4–5.8), and SSPs accounted for 9.4% of polyps with malignant potential (95% CI, 6.6–12.3). The mean prevalence was higher when assessed through high-performance examinations (9.1%; 95% CI, 4.0–14.2; P = .04) and with an alternative definition of clinically relevant serrated polyps (12.3%; 95% CI, 9.3–15.4; P < .001). Increases in prevalence with age were not statistically significant, and prevalence did not differ significantly by sex. Compared with adenomas, a higher proportion of SSPs were solitary (69.0%; 95% CI, 45.9–92.1; P = .08), with diameters of 10 mm or more (19.3%; 95% CI, 12.4–26.2; P = .13) and were proximal (71.5%; 95% CI, 63.5–79.5; P = .008). The mean ages for detection of SSP without dysplasia, with any or low-grade dysplasia, and with high-grade dysplasia were 60.8 years, 65.6 years, and 70.2 years, respectively. The range for proportions of SSPs with dysplasia was 3.7%–42.9% across studies, possibly reflecting different study populations. Conclusions: In a systematic review, we found that SSPs are relatively uncommon compared with adenoma. More research is needed on appropriate diagnostic criteria, variations in detection, and long-term risk

Risk Factors for Metachronous Colorectal Cancer or Advanced Adenomas After Endoscopic Resection of Highrisk Adenomas

Background & aims: Among the characteristics of high-risk adenomas (HRAs), some may predict a higher risk of metachronous advanced lesions. Our aim was to assess which HRA characteristics are associated with high risk of metachronous colorectal cancer (CRC) or advanced adenomas (AAs). Methods: We systematically searched Pubmed, EMBASE, and Cochrane for cohort studies and clinical trials of CRC or AA incidence at surveillance stratified by baseline lesion size, histology, and multiplicity. We calculated pooled relative risks (RRs) using a random-effects model. Heterogeneity was assessed with the I2 statistic. Results: Fifty-five studies were included, with 936,540 patients with mean follow-up 5.4 ± 2.9 years. CRC incidence per 1000 person-years was 2.6 (2.1-3.0) for adenomas ≥20 mm, 2.7 (2.2-3.2) for high-grade dysplasia (HGD), 2.0 (1.8-2.3) for villous component, 0.8 (0.1-1.4) for ≥5 adenomas, 1.0 (0.7-1.2) for ≥3 adenomas. Metachronous CRC risk was higher in adenomas ≥20 mm vs 10 to 19 mm (RR, 2.08; 95% confidence interval [CI], 1.20-3.61), HGD vs low-grade dysplasia (RR, 2.89; 95% CI, 1.88-4.44), villous vs tubular (RR, 1.75; 95% CI, 1.33-2.31). No significant differences in CRC risk were found in ≥3 adenomas vs 1 to 2 (RR, 1.24; 95% CI, 0.84-1.83), nor in ≥5 adenomas vs 3 to 4 (RR, 0.79; 95% CI, 0.30-2.11). Compared with normal colonoscopy, RR for CRC risk was 2.61 (95% CI, 2.06-3.32) for ≥10mm, 6.62 (95% CI, 4.60-9.52) for HGD, 3.58 (95% CI, 2.24-5.73) for villous component, and 2.03 (95% CI, 1.40-2.94) for ≥3 adenomas. Similar trends were seen for metachronous AAs. Conclusion: Metachronous CRC risk is highest in patients with baseline adenomas with ≥20 mm or HGD. Multiplicity does not seem to be associated with substantially higher CRC risk in the near term

An Efficient Strategy for Evaluating New Non-invasive Screening Tests for Colorectal Cancer: The Guiding Principles

OBJECTIVE: New screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers. DESIGN: A formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles. RESULTS: Twelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test\u27s ability to discriminate between CRC and non-cancer states ( CONCLUSION: New non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact

An efficient strategy for evaluating new non-invasive screening tests for colorectal cancer: the guiding principles

Objective: New screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers. Design: A formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles. Results: Twelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test’s ability to discriminate between CRC and non-cancer states (phase I), followed by prospective estimation of accuracy across the continuum of neoplastic lesions in neoplasia-enriched populations (phase II). If these show promise, a provisional test positivity threshold is set before evaluation in typical screening populations. Phase III prospective studies determine single round intention-to-screen programme outcomes and confirm the test positivity threshold. Phase IV studies involve evaluation over repeated screening rounds with monitoring for missed lesions. Phases III and IV findings will provide the real-world data required to model test impact on CRC mortality and incidence. Conclusion: New non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact