Long-term Colorectal Cancer Risk Research Articles

Negative screening colonoscopy and long-term colorectal cancer risk—is it time to extend the screening interval?

Negative screening colonoscopy and long-term colorectal cancer risk—is it time to extend the screening interval?

Low Incidence of Colorectal Advanced Neoplasia During Surveillance in Individuals with a Family History of Colorectal Cancer

BackgroundFamily history of colorectal cancer (CRC) is used to stratify individuals into risk categories which determine timing of initial screening and ongoing CRC surveillance. Evidence for long-term CRC risk following a normal index colonoscopy in family history populations is limited.AimsTo assess the incidence of advanced neoplasia and associated risk factors in a population undergoing surveillance colonoscopies due to family history of CRC.MethodsSurveillance colonoscopy findings were examined in 425 individuals with a family history of CRC, a normal index colonoscopy and a minimum of 10 years of follow-up colonoscopies. Advanced neoplasia risk was determined for three CRC family history categories (near-average, medium and high-risk), accounting for demographics and time after the first colonoscopy.ResultsThe median follow-up was 13.5 years (IQR 11.5–16.0), with an incidence of advanced neoplasia of 14.35% (61/425). The number of affected relatives and age of CRC diagnosis in the youngest relative did not predict the risk of advanced neoplasia (p > 0.05), with no significant differences in advanced neoplasia incidence between the family history categories (p = 0.16). Patients ≥ 60 years showed a fourfold (HR 4.14, 95% CI 1.33–12.89) higher advanced neoplasia risk during surveillance than those < 40 years at index colonoscopy. With each subsequent negative colonoscopy, the risk of advanced neoplasia at ongoing surveillance was reduced.ConclusionsThe incidence of advanced neoplasia was low (14.35%), regardless of the family history risk category, with older age being the main risk for advanced neoplasia. Delaying onset of colonoscopy or lengthening surveillance intervals could be a more efficient use of resources in this population.

Using New Hampshire Colonoscopy Registry data to assess United States and European post-polypectomy surveillance guidelines.

Our goal was to compare the updated European Society of Gastrointestinal Endoscopy (ESGE) and United States Multi-Society Task Force on Colorectal Cancer (USMSTF) high risk groups in predicting metachronous advanced neoplasia on first follow-up colonoscopy and long-term colorectal cancer (CRC). We compared advanced metachronous neoplasia risk (serrated polyps ≥ 1 cm or with dysplasia, advanced adenomas [≥ 1 cm, villous, high grade dysplasia], CRC) on first surveillance colonoscopy in patients with high risk findings according to ESGE versus USMSTF guidelines. We also compared the positive and negative predictive values (PPV, NPV) of both guidelines for metachronous neoplasia. The risk for metachronous neoplasia in our sample (n = 20 458) was higher in the high risk USMSTF (3 year) (13.6 %; 95 %CI 12.3-14.9) and ESGE groups (13.6 %; 95 %CI 12.3-15.0) compared with the lowest risk USMSTF (5.1 %; 95 %CI 4.7-5.5; P < 0.001) and ESGE categories (6.3 %; 95 %CI 6.0-6.7; P < 0.001), respectively. Adding other groups such as USMSTF 5-10-year and 3-5-year groups to the 3-year category resulted in minimal change in the PPV and NPV for metachronous advanced neoplasia. High risk ESGE (hazard ratio [HR] 3.03, 95 %CI 1.97-4.65) and USMSTF (HR 3.07, 95 %CI 2.03-4.66) designations were associated with similar long-term CRC risk (CRC per 100 000 person-years: USMSTF 3-year group 3.54, 95 %CI 2.68-4.68; ESGE high risk group: 3.43, 95 %CI 2.57-4.59). Performance characteristics for the ESGE and USMSTF recommendations are similar in predicting metachronous advanced neoplasia and long-term CRC. The addition of risk groups, such as the USMSTF 5-10-year and 3-5-year groups to the USMSTF 3-year category did not alter the PPV or NPV significantly.

Dietary Intervention for Preventing Colorectal Cancer: A Practical Guide for Physicians.

Colorectal cancer (CRC) is a disease with high prevalence and mortality. Estimated preventability for CRC is approximately 50%, indicating that altering modifiable factors, including diet and body weight, can reduce CRC risk. There is strong evidence that dietary factors including whole grains, high-fiber, red and processed meat, and alcohol can affect the risk of CRC. An alternative strategy for preventing CRC is use of a chemopreventive supplement that provides higher individual exposure to nutrients than what can be obtained from the diet. These include calcium, vitamin D, folate, n-3 polyunsaturated fatty acids, and phytochemicals. Several intervention trials have shown that these dietary chemopreventives have positive protective effects on development and progression CRC. Research on chemoprevention with phytochemicals that possess anti-inflammatory and/or, anti-oxidative properties is still in the preclinical phase. Intentional weight loss by bariatric surgery has not been effective in decreasing long-term CRC risk. Physicians should perform dietary education for patients who are at high risk of cancer for changing their dietary habits and behaviour. An increased understanding of the role of individual nutrients linked to the intestinal micro-environment and stages of carcinogenesis would facilitate the development of the best nutritional formulations for preventing CRC.

Bile acids, bile pigments and colorectal cancer risk.

The gut microbial co-metabolism of bile-derived compounds (e.g. bile acids and bile pigments) affects colorectal cancer (CRC) risk. Here, we review recent findings with focus on selected novel aspects of bile-associated effects with interesting but unclear implications on CRC risk. Numerous studies demonstrated novel biotransformation of bile acids by gut bacteria (e.g. microbial conjugation of bile acids), resulting in diverse bile acid compounds that show complex interactions with host receptors (e.g. FXR, TGR5). In addition, YAP-associated signalling in intestinal epithelial cells is modulated via bile acid receptor TGR5 and contributes to colonic tumorigenesis. Finally, studies indicate that serum levels of the bile pigment bilirubin are inversely associated with CRC risk or intestinal inflammation and that bilirubin affects gut microbiota composition. Bile acids and bile pigments have multiple effects on intestinal microbe-host interactions, which may collectively modulate long-term CRC risk of the host.

Development and validation of a lifestyle-based model for colorectal cancer risk prediction: the LiFeCRC score

BackgroundNutrition and lifestyle have been long established as risk factors for colorectal cancer (CRC). Modifiable lifestyle behaviours bear potential to minimize long-term CRC risk; however, translation of lifestyle information into individualized CRC risk assessment has not been implemented. Lifestyle-based risk models may aid the identification of high-risk individuals, guide referral to screening and motivate behaviour change. We therefore developed and validated a lifestyle-based CRC risk prediction algorithm in an asymptomatic European population.MethodsThe model was based on data from 255,482 participants in the European Prospective Investigation into Cancer and Nutrition (EPIC) study aged 19 to 70 years who were free of cancer at study baseline (1992–2000) and were followed up to 31 September 2010. The model was validated in a sample comprising 74,403 participants selected among five EPIC centres. Over a median follow-up time of 15 years, there were 3645 and 981 colorectal cancer cases in the derivation and validation samples, respectively. Variable selection algorithms in Cox proportional hazard regression and random survival forest (RSF) were used to identify the best predictors among plausible predictor variables. Measures of discrimination and calibration were calculated in derivation and validation samples. To facilitate model communication, a nomogram and a web-based application were developed.ResultsThe final selection model included age, waist circumference, height, smoking, alcohol consumption, physical activity, vegetables, dairy products, processed meat, and sugar and confectionary. The risk score demonstrated good discrimination overall and in sex-specific models. Harrell’s C-index was 0.710 in the derivation cohort and 0.714 in the validation cohort. The model was well calibrated and showed strong agreement between predicted and observed risk. Random survival forest analysis suggested high model robustness. Beyond age, lifestyle data led to improved model performance overall (continuous net reclassification improvement = 0.307 (95% CI 0.264–0.352)), and especially for young individuals below 45 years (continuous net reclassification improvement = 0.364 (95% CI 0.084–0.575)).ConclusionsLiFeCRC score based on age and lifestyle data accurately identifies individuals at risk for incident colorectal cancer in European populations and could contribute to improved prevention through motivating lifestyle change at an individual level.

One negative colonoscopy associated with a significant reduction in colorectal cancer risk.

An observational study published in the Annals of Internal Medicine1 found significant reductions in both colorectal cancer (CRC) incidence and mortality associated with a single negative high-quality screening colonoscopy. The findings indicate an 84% reduction in incidence and a 90% reduction in mortality for up to 17.4 years. As a result, the study authors suggest that the currently recommended 10-year screening interval is safe and could safely be extended. Under current guidelines, average-risk individuals aged 50 years or older who have previously had negative colonoscopy results are recommended to undergo screening every 10 years. That recommendation is based on estimates for how long it takes for adenomas and carcinomas to develop. However, longterm data are lacking on optimum follow-up intervals. The study was conducted by researchers from the Maria Sklodowska-Curie National Research Institute for Oncology in Warsaw, Poland. They analyzed a screening registry of 165,887 people and assessed both long-term CRC risk and CRC death after a single negative low- or high-quality screening colonoscopy. Their findings show that although a single negative screening colonoscopy was associated with significantly reduced CRC incidence and mortality during the 17-year screening period, only a high-quality colonoscopy led to a profound and stable reduction. Among women, high quality was key for long-term efficacy in screening colonoscopy in the proximal colon. These findings are particularly important because previous studies have questioned the efficacy of colonoscopy in the proximal colon as well as screening sigmoidoscopy in women.

Auto-antibodies to p53 and the Subsequent Development of Colorectal Cancer in a United States Prospective Cohort Consortium

Abstract Auto-antibodies to tumor suppressor p53 are found in a subset of colorectal cancer (CRC) patients. A prospective cohort study in the US (Cancer Prevention Study II) has recently reported a statistically significant 1.8-fold increased odds for the development of CRC based on pre-diagnostic sero-positivity for p53; the magnitude of this association decreased with longer time-span between blood sampling and diagnosis. In the present study, we sought to examine this association in a large US CRC cohort consortium to evaluate the potential utility of p53 auto-antibodies as an early CRC detection biomarker. Methods: Antibody responses to p53 were measured in pre-diagnostic blood samples of 3,702 incident CRC cases (median [range] follow-up: 7.3 years [0–40 years]) and an equal number of controls, matched by age, race, and sex, from 9 US prospective cohorts. The association of sero-positivity to p53 with CRC risk, overall and by time between blood draw and diagnosis, was determined by conditional logistic regression. Results: Overall, 5% of controls and 7% of cases were sero-positive to p53, resulting in a statistically significant 33% increased CRC risk (OR: 1.33; 95% CI: 1.09, 1.61). The association was strongest for CRC diagnoses within 2 years after blood draw (OR: 2.73; 95% CI: 1.67, 4.45), with 15% sero-positive cases compared to 6% sero-positive controls. The number of sero-positive cases decreased with longer follow-up time (2–&amp;lt;5 years: 9%; 5–&amp;lt;10 years: 6%; ≥10 years: 3%) down to a proportion similar to that in controls resulting in the absence of an association of p53 sero-positivity with CRC risk after more than 5 years between blood draw and CRC diagnosis. Conclusion: In this large consortium of prospective cohorts, we found that pre-diagnostic sero-positivity to the tumor suppressor p53 was statistically significantly associated with a 2.7-fold increased risk of a subsequent CRC diagnosis within 2 years after blood draw, replicating the findings of the one previous cohort study examining this association. The findings suggest that while p53 sero-positivity may not be a useful predictor of long-term CRC risk, p53 auto-antibodies might be considered as part of a marker panel for early detection of this cancer.

Long-term risk of colorectal cancer after screen-detected adenoma: Experiences from a Danish gFOBT-positive screening cohort.

Fecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all FOBT-positive persons have screen-detected adenomas. Despite removal of these, patients with large/multiple adenomas have increased risk of later developing new advanced adenomas and CRC. International guidelines exist for colonoscopic surveillance following adenoma removal. These divide patients into low-, intermediate- and high-risk groups. We followed 711 FOBT-positive patients with screening adenoma identified during population-based CRC screening in two Danish counties in 2005-2006. As reference population, we included 1,240,348 persons in the same age group from the rest of Denmark not included in the screening. We estimated the long-term CRC risk stratified by adenoma findings during screening and compared to the reference group. After 12 years follow-up, the CRC incidence among all adenoma patients was 322 cases per 100,000 person-years (95% confidence interval [CI]: 212-489) ranging from 251 (95% CI: 94-671) to 542 (95% CI: 300-978) cases per 100,000 person-years in the low- and high-risk groups, respectively. In the reference population, the CRC incidence was 244 (95% CI: 242-247) per 100,000. Patients with screen-detected high-risk adenomas after a positive FOBT had an almost doubled risk of CRC compared to the reference population (adjusted hazard ratio [aHR] 1.95, 95% CI: 1.08-3.51), and the incidence in those with no follow-up visits was over 3.6 (aHR 3.64, 95% CI: 1.82-7.29) times the incidence in the reference population. The increased CRC risk could be controlled if high-risk patients underwent follow-up colonoscopy (aHR 0.87, 95% CI: 0.28-2.69).

Colorectal Cancer Screening Modalities in Chinese Population: Practice and Lessons in Pudong New Area of Shanghai, China.

Background: Parallel test of risk stratification and two-sample qualitative fecal immunochemical tests (FITs) are used to screen colorectal cancer (CRC) in Shanghai, China. This study was designed to identify an optimal initial screening modality based on available data.Methods: A total of 538,278 eligible residents participated in the program during the period of January 2013 to June 2017. Incident CRC was collected through program reporting system and by record linkage with the Shanghai Cancer Registry up to December 2017. Logistic regression model was applied to identify significant factors to calculate risk score for CRC. Cutoff points of risk score were determined based on Youden index and defined specificity. Sensitivity, specificity, and positive predictive values (PPVs) were computed to evaluate validity of assumed screening modalities.Results: A total of 446 CRC were screen-detected, and 777 interval or missed cases were identified through record linkage. The risk score system had an optimal cutoff point of 19 and performed better in detecting CRC and predicting long-term CRC risk than did the risk stratification. When using a cutoff point of 24, parallel test of risk score, and FIT were expected to avoid 56 interval CRCs with minimal decrease in PPV and increase in colonoscopy. However, the observed detection rates were much lower than those expected due to low compliance to colonoscopy.Conclusions: Risk score is superior to risk stratification used in the program, particularly when combined with FIT. Compliance to colonoscopy should be improved to guarantee the effectiveness of CRC screening in the population.

Long-term risk of colorectal cancer after negative colonoscopy in a Danish gFOBT screening cohort.

Faecal occult blood test (FOBT) screening for colorectal cancer (CRC) is implemented in several countries. Approximately half of all screen positive persons have negative colonoscopy, but consensus is lacking on how these persons should be followed up. Health authorities in Denmark and The Netherlands recommend suspending screening for 8-10 years, while patients in UK are invited to screening after 2 years. In this cohort-study, we followed 166,277 individuals invited to FOBT-screening in 2005-2006 and a reference group comprising the remaining 1,240,348 Danes of the same age. We linked Danish population and health service registers to obtain information about colonoscopy outcome and incident CRC. We estimated CRC risk by colonoscopy outcome (adenoma, other colorectal pathology or negative colonoscopy) for the reference group, the screening group, and subgroups. Persons with positive screening FOBT followed by negative colonoscopy had the same long-term CRC risk as persons with adenoma detected due to a positive screening FOBT (aHR 1.33, 95% CI: 0.65-2.71). We found no difference in the long-term CRC risk between persons with negative colonoscopy after a positive FOBT screening test and the unscreened reference population (aHR 1.05, 95% CI: 0.62-1.78). Since FOBT screen positive persons in our study remained at average risk of CRC despite of a negative index colonoscopy, we question the safety of suspending FOBT screening for this group. It needs to be monitored whether recent efforts to improve colonoscopy quality have been successful in ensuring low CRC risk after negative colonoscopy also in FOBT positive persons.

Long-term risk of colorectal cancer in individuals with serrated polyps

ObjectiveAlthough serrated polyps may be precursors of colorectal cancer (CRC), prospective data on the long-term CRC risk in individuals with serrated polyps are lacking.DesignIn a population-based randomised trial, 12 955...

Cigarette smoking and colorectal cancer: Long-term, subsite-specific risks in a cohort study of postmenopausal women

Background & Aims: Cigarette smoking is a putative risk factor for colorectal cancer (CRC). However, long-term CRC risk estimates among female smokers remain limited and inconsistent. The goal of this prospective study was to assess cigarette smoking and CRC risk, overall and by anatomic subsite, among postmenopausal women. Methods: Data were drawn from a large population-based cohort (n = 41,836) of randomly selected women, age 55-69 years at baseline (Iowa Women's Health Study). Cigarette smoking and other CRC risk factors were characterized at baseline (1986). Incident (n = 869) and fatal (n = 249) CRC cases were identified through December 31, 1999. CRC risks were estimated using Cox proportional hazards regression models. Results: Compared with never smokers, ever smokers had slightly increased risks for both incident (relative risk [RR], 1.17; 95% confidence interval [CI], 1.00-1.36) and fatal (RR, 1.31; 95% CI, 0.98-1.74) CRC in multivariate analyses. Incident CRC risks increased progressively by lengthening induction period ( P trend=0.01), reaching a 30% increase (RR, 1.30; 95% CI, 1.04-1.63) after age 45 years. By anatomic subsite, ever smoked cigarettes and induction period were more strongly associated with incident proximal CRC ( P = 0.03 and P trend = 0.03, respectively) than incident distal CRC ( P=0.44 and P trend=0.10, respectively). Conclusions: In this long-term cohort study of postmenopausal women, cigarette smoking was positively associated with CRC risk. Onset of smoking in the distant past appeared to confer the greatest risk, especially for incident proximal CRC. These data support a potential subsite-specific role for cigarette smoking in colorectal carcinogenesis, at least among women. Based on emerging data, an epigenetic pathway for smoking-induced CRC is proposed.

Cigarette smoking and colorectal cancer: long-term, subsite-specific risks in a cohort study of postmenopausal women.

Cigarette smoking is a putative risk factor for colorectal cancer (CRC). However, long-term CRC risk estimates among female smokers remain limited and inconsistent. The goal of this prospective study was to assess cigarette smoking and CRC risk, overall and by anatomic subsite, among postmenopausal women. Data were drawn from a large population-based cohort (n = 41836) of randomly selected women, age 55-69 years at baseline (Iowa Women's Health Study). Cigarette smoking and other CRC risk factors were characterized at baseline (1986). Incident (n = 869) and fatal (n = 249) CRC cases were identified through December 31, 1999. CRC risks were estimated using Cox proportional hazards regression models. Compared with never smokers, ever smokers had slightly increased risks for both incident (relative risk [RR], 1.17; 95% confidence interval [CI], 1.00-1.36) and fatal (RR, 1.31; 95% CI, 0.98-1.74) CRC in multivariate analyses. Incident CRC risks increased progressively by lengthening induction period (P trend=0.01), reaching a 30% increase (RR, 1.30; 95% CI, 1.04-1.63) after age 45 years. By anatomic subsite, ever smoked cigarettes and induction period were more strongly associated with incident proximal CRC (P = 0.03 and P trend = 0.03, respectively) than incident distal CRC (P=0.44 and P trend=0.10, respectively). In this long-term cohort study of postmenopausal women, cigarette smoking was positively associated with CRC risk. Onset of smoking in the distant past appeared to confer the greatest risk, especially for incident proximal CRC. These data support a potential subsite-specific role for cigarette smoking in colorectal carcinogenesis, at least among women. Based on emerging data, an epigenetic pathway for smoking-induced CRC is proposed.