Reduced Risk Of Colorectal Cancer Research Articles

Implementation of patient navigation services to improve colorectal cancer health literacy in a vulnerable community health center population.

e23208 Background: Under-served community populations face social and health inequities which contribute to sub-optimal colorectal cancer (CRC) screening rates and excess mortality risk. Furthermore, these populations may not have the health literacy or food security necessary to mitigate the well-established nutrition-related risk of CRC. This quality improvement study aimed to improve CRC-related health literacy and dietary habits, with the additional goal of improving screening rates in our disadvantaged community health center population. Methods: This single-institutional study utilized the Plan-Do-Study-Act (PDSA) model to implement patient navigation services and administer a cross-sectional survey evaluating nutrition-related CRC risk. Patients eligible for screening were contacted by patient outreach coordinators prior to scheduled primary care appointments, and the survey was administered. During patient visits, outreach coordinators met with them to provide 1:1 education addressing CRC prevention, screening and nutrition. Information on free or low-cost fresh food options was provided to help address barriers such as food insecurity. The outreach coordinators also liaised with physicians to assist with coordination to services. Results: Prior to the intervention 58% of survey respondents (25/43) were not aware of any foods or dietary habits that decreased the risk of colorectal cancer; 51% (22/43) were not aware of foods that increased the risk of colorectal cancer. Most respondents (54%) were in fact not at all worried about possibly developing CRC in their lifetimes (22/41), while 34% (14/41) were a little worried, and the remainder (12%) very or extremely worried. 97% of respondents (33/34) felt more knowledgeable about CRC screening and felt more confident about improving their nutrition to reduce CRC risk after receiving the educational intervention, while 94% of respondents (31/33) stated they would subsequently make dietary changes. Conclusions: Health literacy regarding colorectal cancer was low in this underserved community population. Implementation of a patient navigation intervention led to increased knowledge and confidence in modifying dietary risk factors. However, preliminary data review did not reveal significant change in CRC screening rates during the initial phase of the intervention. One of the initially identified barriers included system-level delays in colonoscopy access. During the Act phase of the PDSA model, patient navigation services will be further optimized by workflow adaptation based on the response of outreach coordinators and patient-reported barriers regarding stool-based testing. [Table: see text]

A causal analysis of the relationship between exposure to sunlight and colorectal cancer risk: A Mendelian randomization study.

Several observational studies have found that exposure to sunlight reduces the risk of colorectal cancer (CRC). However, sun exposure remains ambiguous in its relationship to CRC. We carried out a Mendelian randomization (MR) study to explore the potential associations between them. We examined the exposure to sunlight summary statistics of the UK Biobank Consortium using a 2-sample MR analysis. Using data from the FinnGen consortium, we derived summary statistics for CRC. We conducted our analysis with various methods, incorporating inverse variance weighted (IVW) along with 4 other approaches. A Cochran Q statistic was used to measure the heterogeneity of instrumental variables (IVs). We screened 133 single nucleotide polymorphisms (SNPs) (time spent outdoors in summer), 41 SNPs (time spent outdoors in winter), and 35 SNPs (frequency of solarium/sunlamp use) representing sunlight exposure for MR analysis. All selected SNPs had an F-statistic >20, indicating that IVs did not weakly bias the results. The summer outdoor activity trait exhibited significant heterogeneity (Cochran Q statistic = 183.795, P = .002 < 0.05), but we found no horizontal polymorphisms or significant heterogeneity for the other exposure traits. According to IVW estimates, no causal association exists between time spent outdoors in summer and CRC (Odds Ratio, OR = 0.735, 95% confidence interval, CI = 0.494-1.017, P = .128 > 0.017). No causal relationship existed between time spent outdoors in winter and CRC, as indicated by Bonferroni-corrected adjusted p-values. The OR was 0.877 with a 95% CI of 0.334-2.299, and the P value was .789, more significant than the significance threshold of 0.017. The solarium/sunlamp use frequency was not associated with CRC (OR = 1.567, 95%CI = 0.243-10.119, P = .637 > .017). Also, an IVW with random effects was applied to determine the causal relationship between summer outdoor time and CRC. No causal association between summer outdoor time and CRC was found (OR = 0.735, 95% CI = 0.494-1.017, P = .128 > .017). Additionally, 4 additional analyses yielded similar results. The findings of our study suggest that exposure to sunlight may reduce CRC risk, but the causal relationship remains unsolved. There is no evidence to suggest that exposure to sunlight prevents CRC. Randomized, controlled trials are needed to determine whether sunlight exposure protects against CRC.

Association of healthy diet score and adiposity with risk of colorectal cancer: findings from the UK Biobank prospective cohort study.

To explore the joint association of dietary patterns and adiposity with colorectal cancer (CRC), and whether adiposity mediates the relationship between dietary patterns and CRC risk, which could provide deeper insights into the underlying pathogenesis of CRC. The data of 307,023 participants recruited between 2006 and 2010 were extracted from the UK Biobank study. Healthy diet scores were calculated based on self-reported dietary data at baseline, and participants were categorized into three groups, namely, low, intermediate, and high diet score groups. Cox regression models with hazard ratios (HRs) and 95% confidence intervals (CIs) were used to estimate the effects of the healthy diet score on CRC incidence, adjusting for various covariates. Furthermore, the mediation roles of obesity and central obesity between the healthy diet score and CRC risk were assessed using a counterfactual causal analysis based on Cox regression model. Additionally, joint association between dietary patterns and adiposity on CRC risks was assessed on the additive and multiplicative scales. Over a median 6.2-year follow-up, 3,276 participants developed CRC. After adjusting for sociodemographic and lifestyle factors, a lower risk of CRC incidence was found for participants with intermediate (HR = 0.83, 95% CI: 0.72 to 0.95) and high diet scores (HR = 0.73, 95% CI: 0.62 to 0.87) compared to those with low diet scores. When compared with the low diet score group, obesity accounted for 4.13% and 7.93% of the total CRC effect in the intermediate and high diet score groups, respectively, while central obesity contributed to 3.68% and 10.02% of the total CRC risk in the intermediate and high diet score groups, respectively. The mediating effect of adiposity on CRC risk was significant in men but not in women. Concurrent unhealthy diet and adiposity multiplied CRC risk. Adiposity-mediated effects were limited in the link between dietary patterns and CRC incidence, implying that solely addressing adiposity may not sufficiently reduce CRC risk. Interventions, such as improving dietary quality in people with adiposity or promoting weight control in those with unhealthy eating habits, may provide an effective strategy to reduce CRC risk.

Genetic risk impacts the association of menopausal hormone therapy with colorectal cancer risk.

Menopausal hormone therapy (MHT), a common treatment to relieve symptoms of menopause, is associated with a lower risk of colorectal cancer (CRC). To inform CRC risk prediction and MHT risk-benefit assessment, we aimed to evaluate the joint association of a polygenic risk score (PRS) for CRC and MHT on CRC risk. We used data from 28,486 postmenopausal women (11,519 cases and 16,967 controls) of European descent. A PRS based on 141 CRC-associated genetic variants was modeled as a categorical variable in quartiles. Multiplicative interaction between PRS and MHT use was evaluated using logistic regression. Additive interaction was measured using the relative excess risk due to interaction (RERI). 30-year cumulative risks of CRC for 50-year-old women according to MHT use and PRS were calculated. The reduction in odds ratios by MHT use was larger in women within the highest quartile of PRS compared to that in women within the lowest quartile of PRS (p-value = 2.7 × 10-8). At the highest quartile of PRS, the 30-year CRC risk was statistically significantly lower for women taking any MHT than for women not taking any MHT, 3.7% (3.3%-4.0%) vs 6.1% (5.7%-6.5%) (difference 2.4%, P-value = 1.83 × 10-14); these differences were also statistically significant but smaller in magnitude in the lowest PRS quartile, 1.6% (1.4%-1.8%) vs 2.2% (1.9%-2.4%) (difference 0.6%, P-value = 1.01 × 10-3), indicating 4 times greater reduction in absolute risk associated with any MHT use in the highest compared to the lowest quartile of genetic CRC risk. MHT use has a greater impact on the reduction of CRC risk for women at higher genetic risk. These findings have implications for the development of risk prediction models for CRC and potentially for the consideration of genetic information in the risk-benefit assessment of MHT use.

Should I Take Aspirin? (SITA): RCT of a decision aid for cancer chemoprevention.

Background Australian guidelines recommend that all people aged 50-70 years old consider taking low-dose aspirin to reduce the risk of colorectal cancer (CRC). Aim To determine the effect of a consultation with a researcher in general practice using a decision aid about taking low-dose aspirin to prevent CRC on informed decision-making and low-dose aspirin uptake compared to a general CRC prevention brochure. Design and Setting Individually randomised controlled trial in six general practices in Victoria, Australia, from October 2020 to March 2021. Method Patients aged 50-70 years attending a general practitioner (GP) were recruited consecutively. The intervention was a consultation using a decision aid to discuss taking aspirin to reduce CRC risk; control consultations discussed reducing CRC risk generally. The self-reported co-primary outcomes were informed choices about taking aspirin at one month and low-dose aspirin uptake at six months. Results 261 participants (86% of eligible patients) were randomised into trial arms (129 intervention, 132 control). 17.7% (20/113) of intervention and 7.6% (9/118) control participants reported making an informed choice at one month, an estimated 9.1% (95% CI 0.29% to 18.5) between-arm difference in proportions [odds ratio (OR) 2.47 (97.5% CI:0.94 to 6.52) p=0.074]. The proportions of individuals who reported using aspirin at six months were: 10.2% (12/118) intervention vs 13.8% (16/116) control (estimated between-arm difference: -4.0% (95% CI: -13.5 to 5.5); [OR= 0.68 (97.5% CI:0.27 to 1.70), p= 0.692]. Conclusion The decision aid improved informed decision-making; but has little effect on long-term regular use of aspirin to reduce CRC risk.

The interaction effect of dietary selenium intake and the IL10 rs1800871 polymorphism on the risk of colorectal cancer: a case-control study in Korea.

The importance of Se in human health has received much attention due to its antioxidant properties when it is consumed at an appropriate level. However, the existing evidence is limited to obtain an effective conclusion for colorectal cancer (CRC). Notably, an adequate intake of Se was reported for Koreans. Furthermore, cytokine secretion and immune function may be affected by dietary Se. Our study aimed to explore whether Se potentially reduces CRC risk and whether the IL10 rs1800871 polymorphism has an effect on this association. We designed a case-control study with 1420 cases and 2840 controls. A semi-quantitative FFQ was used to obtain information on Se intake. We determined IL10 rs1800871 through genetic analysis. Different models were developed to explore Se intake related to CRC risk by calculating OR and 95 % CI using unconditional logistic regression. A reduced risk of CRC was found as Se intake increased, with an OR (95 % CI) of 0·44 (0·35, 0·55) (Pfor trend < 0·001). However, this association seems to be allele-specific and only present among risk variant allele carriers (GA/GG) with a significant interaction between dietary Se and IL10 rs1800871 (Pfor interaction = 0·043). We emphasised that a reduction in CRC risk is associated with appropriate Se intake. However, the IL10 rs1800871 polymorphism has an impact on this reduction, with a greater effect on variant allele carriers. These findings suggest the importance of considering an individual's genetic characteristics when developing nutritional strategies for CRC prevention.

A causality between fruit consumption and colorectal cancer: a two-sample Mendelian randomization analysis.

Colorectal cancer (CRC) significantly threatens human health with increasing incidence and mortality. A debate continues whether fruit consumption is associated with CRC, despite dietary habits having an impact on the disease. The study aims to examine the causal relationship between fruit consumption and CRC based on a two-sample Mendelian randomization method (MR). Summary statistics for fruit consumption and CRC were obtained from the UK Biobank and the FinnGen Consortium, respectively. Analysis methods used in this study included the inverse-variance weighted (IVW), MR Egger, weighted median, simple mode, and weighted mode. Heterogeneity and horizontal pleiotropy were also assessed. Additionally, a leave-one-out analysis was performed to validate the robustness of the results. We found that fruit consumption was associated with a reduction in CRC risk by the IVW method (P = 0.021). This protective effect was predominantly observed in males (OR 0.374; 95% CI: 0.157-0.892; P = 0.027), while no protective effect was noted in females. However, causal correlations were not observed upon analyzing 16 individual types of fruits. Moreover, our results were unlikely to be influenced by horizontal pleiotropy and heterogeneity. Leave-one-out analysis confirmed the stability of the results. Our findings suggest that a genetic predisposition for fruit consumption may be protective against CRC, underscoring the need for further research to elucidate the underlying mechanisms and dietary patterns involved.

Partial substitution of red or processed meat with plant-based foods and colorectal cancer risk

Abstract Background Consumption of plant-based foods, particularly whole grains, may decrease colorectal cancer (CRC) risk, while red and processed meat consumption increases it. Moreover, shifting to more plant-based diets promotes sustainable food systems. Yet, few studies have examined the impact of dietary shifts towards more plant-based diets on CRC risk. We modelled a partial substitution of red or processed meat with whole grains, vegetables or fruits in relation to CRC risk in Finnish adults. Methods Our data comprised 43 788 participants (79% men) aged ≥25 years from five Finnish cohorts. The median follow-up was 29 years, during which 1124 CRC cases were diagnosed. Diet was assessed by a validated food frequency questionnaire. We modelled substitutions of 100g/week of red meat or 50g/week of processed meat with an equivalent amount of plant-based foods. In a two-stage meta-analysis, cohort-specific hazard ratios (HR) were calculated using Cox proportional hazards model and pooled together. We adjusted the analyses for sex and other relevant confounders. Results We observed a small decrease in CRC risk when red or processed meat was partially substituted with vegetables (red meat: HR 0.97, 95% CI 0.94-0.99, P = 0.008; processed meat: 0.99, 0.98-1.00, P = 0.029) or fruits (red meat: 0.97, 0.94-0.99, P = 0.007; processed meat: 0.99, 0.98-1.00, P = 0.036). No association occurred between the partial substitution of red or processed meat with whole grains and CRC risk. Conclusions Our results suggested that already small and easily implemented substitutions of red or processed meat with vegetables or fruits could reduce CRC risk in Finnish adults. The findings highlight the need for effective nutrition policy actions to promote the shift towards more plant-based diets that would benefit both public health and sustainable food systems. Further research on similar substitutions in relation to CRC risk is required in different populations and real-life settings. Key messages • Already small and easily implemented substitutions of 100g/week of red meat or 50g/week of processed meat with vegetables or fruits could reduce colorectal cancer risk in Finnish adults. • The findings highlight the need for effective nutrition policy actions to promote the shift towards more plant-based diets that would benefit both public health and the sustainability of food systems.

Assessments of dietary intake and polygenic risk score in associations with colorectal cancer risk: evidence from the UK Biobank

BackgroundThis study aimed to explore the potential interaction between dietary intake and genetics on incident colorectal cancer (CRC) and whether adherence to healthy dietary habits could attenuate CRC risk in individuals at high genetic risk.MethodsWe analyzed prospective cohort data of 374,004 participants who were free of any cancers at enrollment in UK Biobank. Dietary scores were created based on three dietary recommendations of the World Cancer Research Fund (WCRF) and the overall effects of 11 foods on CRC risks using the inverse-variance (IV) method. Genetic risk was assessed using a polygenic risk score (PRS) capturing overall CRC risk. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% CIs (confidence intervals) of associations. Interactions between dietary factors and the PRS were examined using a likelihood ratio test to compare models with and without the interaction term.ResultsDuring a median follow-up of 12.4 years, 4,686 CRC cases were newly diagnosed. Both low adherence to the WCRF recommendations (HR = 1.12, 95% CI = 1.05–1.19) and high IV-weighted dietary scores (HR = 1.27, 95% CI = 1.18–1.37) were associated with CRC risks. The PRS of 98 genetic variants was associated with an increased CRC risk (HRT3vsT1 = 2.12, 95% CI = 1.97–2.29). Participants with both unfavorable dietary habits and a high PRS had a more than twofold increased risk of developing CRC; however, the interaction was not significant. Adherence to an overall healthy diet might attenuate CRC risks in those with high genetic risks (HR = 1.21, 95% CI = 1.08–1.35 for high vs. low IV-weighted dietary scores), while adherence to WCRF dietary recommendations showed marginal effects only (HR = 1.09, 95% CI = 1.00–1.19 for low vs. high WCRF dietary scores).ConclusionDietary habits and the PRS were independently associated with CRC risks. Adherence to healthy dietary habits may exert beneficial effects on CRC risk reduction in individuals at high genetic risk.

Polymorphisms in Cyclooxygenase, Lipoxygenase and TP53 genes predict colorectal polyp risk reduction by aspirin in the seAFOod polyp prevention trial.

Aspirin and eicosapentaenoic acid (EPA) reduce colorectal adenomatous polyp risk and affect synthesis of oxylipins including prostaglandin E2. We investigated whether 35 single nucleotide polymorphisms (SNPs) in oxylipin metabolism genes such as cyclooxygenase [PTGS] and lipoxygenase [ALOX], as well as 7 SNPs already associated with colorectal cancer (CRC) risk reduction by aspirin (eg. TP53; rs104522), modified the effects of aspirin and EPA on colorectal polyp recurrence in the randomised 2x2 factorial seAFOod trial. Treatment effects were reported as the incidence rate ratio (IRR) and 95% confidence interval (CI) by stratifying negative binomial and Poisson regression analyses of colorectal polyp risk on SNP genotype. Statistical significance was reported with adjustment for the false discovery rate as the P and q value. Five hundred and forty-two (of 707) trial participants had both genotype and colonoscopy outcome data. Reduction in colorectal polyp risk in aspirin users compared with non-aspirin users was restricted to rs4837960 (PTGS1) common homozygotes (IRR 0.69 [95%CI 0.53,0.90]; q=0.06), rs2745557 (PTGS2) compound heterozygote-rare homozygotes (IRR 0.60 [0.41,0.88]; q=0.06), rs7090328 (ALOX5) rare homozygotes (IRR 0.27 [0.11,0.64]; q=0.05), rs2073438 (ALOX12) common homozygotes (IRR 0.57 [0.41,0.80]; q=0.05), and rs104522 (TP53) rare homozygotes (IRR 0.37 [0.17,0.79]; q=0.06). No modification of colorectal polyp risk in EPA users was observed. In conclusion, genetic variants relevant to the proposed mechanism of action on oxylipins are associated with differential colorectal polyp risk reduction by aspirin in individuals who develop multiple colorectal polyps. SNP genotypes should be considered during development of personalised, predictive models of CRC chemoprevention by aspirin.

Association between nutrient intake related to the one-carbon metabolism and colorectal cancer risk: a case–control study in the Basque Country

PurposeEpidemiologic evidence for the association between methyl-donor nutrient intake and colorectal cancer (CRC) risk remains inconclusive. We aimed to examine the relationship between intake of vitamins of the B group, methionine, total choline and betaine and CRC risk, in a population from the CRC screening programme in the Basque Country.DesignThis observational study included 308 patients with CRC and 308 age- and sex-matched subjects as controls. During recruitment, dietary, anthropometric, lifestyle, socioeconomic, demographic, and health status information was collected. Conditional logistic regression was used to estimate the odds ratios (ORs) for CRC risk.ResultsThe adjusted ORs for CRC risk decreased with higher intakes of choline and betaine (p < 0.05). After further adjustment for folate, high intake of choline and betaine remained associated with a reduced CRC risk (adjusted model for choline, OR third tertile vs first tertile = 0.45, 95% CI 0.26–0.80, p = 0.006; for betaine, OR third tertile vs first tertile = 0.27, 95% CI 0.16–0.47, p < 0.001). Regarding the other nutrients, our findings indicated a non-significant decrease in CRC risk with the high level of intake.ConclusionsOur data suggest that choline and betaine intake influence CRC risk in the studied population.

Endoscopic Removal of Premalignant Lesions Reduces Long-Term Colorectal Cancer Risk: Results From the Japan Polyp Study

To date, no regional evidence of long-term colorectal cancer (CRC) risk reduction after endoscopic premalignant lesion removal has been established. We aimed to analyze this over a long-term follow-up evaluation. This was a prospective cohort study of participants from the Japan Polyp Study conducted at 11 Japanese institutions. Participants underwent scheduled follow-up colonoscopies after a 2-round baseline colonoscopy process. The primary outcome was CRC incidence after randomization. The observed/expected ratio of CRC was calculated using data from the population-based Osaka Cancer Registry. Secondary outcomes were the incidence and characteristics of advanced neoplasia (AN). A total of 1895 participants were analyzed. The mean number of follow-up colonoscopies and the median follow-up period were 2.8 years (range, 1-15 y) and 6.1 years (range, 0.8-11.9 y; 11,559.5 person-years), respectively. Overall, 4 patients (all males) developed CRCs during the study period. The observed/expected ratios for CRC in all participants, males, and females, were as follows: 0.14 (86% reduction), 0.18, and 0, respectively, and 77 ANs were detected in 71 patients (6.1 per 1000 person-years). Of the 77 ANs detected, 31 lesions (40.3%) were laterally spreading tumors, nongranular type. Nonpolypoid colorectal neoplasms (NP-CRNs), including flat (<10 mm), depressed, and laterally spreading, accounted for 59.7% of all detected ANs. Furthermore, 2 of the 4 CRCs corresponded to T1 NP-CRNs. Endoscopic removal of premalignant lesions, including NP-CRNs, effectively reduced CRC risk. More than half of metachronous ANs removed by surveillance colonoscopy were NP-CRNs. The Japan Polyp Study: University Hospital Medical Information Network Clinical Trial Registry: University Hospital Medical Information Network Clinical Trial Registry, C000000058; cohort study: UMIN000040731.

When gold standards are not so golden: prevalence bias in randomized trials on endoscopic colorectal cancer screening

Randomized trials on the effectiveness of screening endoscopy in reducing colorectal cancer (CRC) risk have reported statistically significant, but rather modest reduction of CRC risk by the screening offer. However, risk estimates in these trials included substantial proportions of prevalent CRC cases which were early detected, but could not possibly have been prevented by screening. Thereby, a key principle of randomized prevention trials is violated that only “at risk” persons who do not yet have the disease one aims to prevent should be included in measures of preventive effects. Using recently published data from the Nordic-European Initiative on Colorectal Cancer (NordICC) trial as an example, we illustrate that approaches aimed to account for “prevalence bias” lead to effect estimates that are substantially larger than those reported in the trial and more in line with results from observational studies and real life settings. More rigorous methodological work is needed to develop effective and user-friendly tools to prevent or adjust for prevalence bias in future screening studies.

Alteration of Metabolic Syndrome Is Associated with the Decreased Risk of Colorectal Cancer.

Metabolic syndrome (MetS) can be resolved through active control. We aimed to examine the effect of changes in MetS status on colorectal cancer (CRC) risk. A total of 5,704,611 Korean national insurance beneficiaries that received two consecutive biennial mandatory health exams (2009-2011) were followed-up until 2017. MetS was determined as the presence of at least three of five components. Participants were categorized into four groups according to the change in MetS status; MetS-never, -resolved, -developed, or -persistent. A Cox proportional hazards model adjusted for age, sex, smoking, alcohol drinking, and physical exercise was used. Participants who recovered from MetS had a higher risk of CRC than those free of MetS but had a lower risk than those with persistent MetS (HR: 0.91, 95% CI: 0.86-0.95 vs. HR: 0.75, 95% CI: 0.73-0.78; reference: persistence group). Among the five MetS components, resolving high blood pressure, abdominal obesity, and blood sugar had a preventive effect on CRC prevention, while normalization of lipid profile did not reduce CRC risk independently. Resolving MetS could reduce CRC risk compared to having persistent MetS, indicating the necessity of considering control of MetS as a CRC prevention policy.

Adherence to the Paleolithic diet and Paleolithic-like lifestyle reduce the risk of colorectal cancer in the United States: a prospective cohort study

BackgroundThe plant-based paleolithic diet (PD) and the paleolithic-like lifestyle (PLL) may reduce the risk of chronic diseases, including colorectal adenomas. These dietary and lifestyle approaches are proposed to exert their effects through mechanisms such as reducing inflammation, oxidative stress, and insulin levels. However, whether PD and PLL is associated with the risk of colorectal cancer (CRC) has not been determined.MethodsA cohort of 74,721 individuals who participated in the PLCO study were included in this analysis. Adherence to the PD and PLL was assessed using PD and PLL scores, where higher scores indicated greater adherence. Multivariable Cox models were utilized to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the risk of CRC and its subsites (proximal colon cancer and distal CRC). Subgroup analyses were conducted to identify potential effect modifiers.ResultsDuring a mean follow-up of 9.2 years, a total of 694 CRC cases were identified. Participants in the highest compared with the lowest quartiles of PD score had a lower risk of CRC (Q4 vs Q1: HR 0.76, 95% CI 0.61–0.95, Ptrend = 0.009) and proximal colon cancer (Q4 vs Q1: HR 0.73, 95% CI 0.55–0.97, Ptrend = 0.02). A stronger inverse association was observed for PLL score with the risk of CRC (Q4 vs Q1: HR 0.64, 95% CI 0.51–0.81, Ptrend < 0.001), proximal colon (Q4 vs Q1: HR 0.62, 95% CI 0.46–0.83, Ptrend = 0.001) and distal CRC (Q4 vs Q1: HR 0.69, 95% CI 0.48–0.98, Ptrend = 0.03). Subgroup analyses revealed the inverse association of PD score with the risk of CRC was more pronounced in participants with BMI < 30 (Q4 vs Q1: HR 0.68, 95% CI 0.53–0.87) than in those with BMI ≥ 30 (Q4 vs Q1: HR 1.07, 95% CI 0.68–1.67) (Pinteraction = 0.02).ConclusionsOur findings suggest that adhering to the PD and PLL could be a new option to reduce CRC risk.

Identifying and ranking causal microbial biomarkers for colorectal cancer at different cancer subsites and stages: a Mendelian randomization study.

The gut microbiome is directly involved in colorectal carcinogenesis, but much of the epidemiological evidence for the effect of the gut microbiome on colorectal cancer (CRC) risk comes from observational studies, and it is unclear whether identified microbial alterations are the cause or consequence of CRC development. Univariate Mendelian randomization (MR) analysis and multivariate MR analysis based on Bayesian model averaging were performed to comprehensively explore the microbial risk factors associated with CRC. The Network Module Structure Shift method was used to identify microbial biomarkers associated with CRC. Mediation analysis was used to explore the dietary habits-microbiota-CRC pathway. The results of the four methods showed that 9 bacteria had a robust causal relationship with the development of CRC. Among them, Streptococcus thermophilus reduced the risk of CRC; Eubacterium ventriosum and Streptococcus were beneficial bacteria of malignant tumors of colon (CC); Erysipelotrichaceae was a protective factor for malignant tumors of rectal (CR); Bacteroides ovatus was a risk factor for benign tumors. Finally, the mediation analysis revealed 10 pathways by which dietary regulation bacteria affected the risk of CRC, including alcohol consumption increased the risk of CC by reducing the abundance of Eubacterium ventriosum (mediated proportion: 43.044%), and the mediated proportion of other pathways was 7.026%-34.22%. These findings will contribute to the understanding of the different carcinogenic mechanisms of intestinal flora in the colon and rectum and the risk of tumor transformation, thereby aiding CRC prevention, early screening, and the development of future strategies to reduce CRC risk.

The Impact of Bariatric Surgery on the Incidence of Colorectal Cancer in Patients with Obesity—a Systematic Review and Meta-analysis of Registry Data

PurposeCancer and obesity represent two of the most significant global health concerns. The risk of malignancy, including colorectal cancer (CRC), increases with obesity. The aim of this study was to perform a systematic review and meta-analysis to determine the value of bariatric surgery in reducing CRC risk in patients with obesity using registry data.Materials and MethodsA systematic review and meta-analysis were performed as per PRISMA guidelines. The risk of CRC was expressed as a dichotomous variable and reported as odds ratios (OR) with 95% confidence intervals (CIs) using the Mantel-Haenszel method. A multi-treatment comparison was performed, examining the risk reduction associated with existing bariatric surgery techniques. Analysis was performed using RevMan, R packages, and Shiny.ResultsData from 11 registries including 6,214,682 patients with obesity were analyzed. Of these, 14.0% underwent bariatric surgery (872,499/6,214,682), and 86.0% did not undergo surgery (5,432,183/6,214,682). The mean age was 49.8 years, and mean follow-up was 5.1 years. In total, 0.6% of patients who underwent bariatric surgery developed CRC (4,843/872,499), as did 1.0% of unoperated patients with obesity (54,721/5,432,183). Patients with obesity who underwent bariatric surgery were less likely to develop CRC (OR: 0.53, 95% CI: 0.36–0.77, P < 0.001, I2 = 99%). Patients with obesity undergoing gastric bypass surgery (GB) (OR: 0.513, 95% CI: 0.336–0.818) and sleeve gastrectomy (SG) (OR: 0.484, 95% CI: 0.307–0.763) were less likely to develop CRC than unoperated patients.ConclusionAt a population level, bariatric surgery is associated with reduced CRC risk in patients with obesity. GB and SG are associated with the most significant reduction in CRC risk.PROSPERO RegistrationCRD42022313280.Graphical

Vitamin E intake and paraoxonase 1 (PON1) rs662 genetic polymorphism are associated with colorectal cancer risk in a Korean population

Vitamin E and paraoxonase 1 (PON1) are associated with cancer development. However, their interactive effect on colorectal cancer (CRC) risk is inconclusive. We conducted a case–control study including 1,351 CRC patients and 2,670 controls at the Korean National Cancer Centre (KNCC). There was an inverse association between vitamin E intake and CRC risk (odds ratio (OR) = 0.31; 95% confidence interval (CI) = 0.22–0.42). We identified a reduced CRC risk among individuals with CC genotype of PON1 rs662 polymorphism compared with subjects carrying the T allele (OR = 0.74; 95% CI = 0.61–0.90). The highest interaction between vitamin E intake and PON1 rs662 variants was significant for the subjects carrying the CC genotype (p-interaction = 0.014). This study provided further supporting evidence that vitamin E intake is associated with lower odds of CRC. Furthermore, the activity of vitamin E is strengthened among individuals carrying C allele of the PON1 rs662 polymorphism.

Impact of bariatric surgery on early-onset colorectal cancer risk: a systematic review and meta-analysis.

The aim of this meta-analysis is to determine the impact of bariatric surgery on the risk of early-onset colorectal neoplasia. This systematic review was conducted according to PRISMA recommendations. It was registered in the PROSPERO international database. A comprehensive search was conducted in electronic databases (MEDLINE, EMBASE, and Web of Science) for completed studies until May 2022. The Search was made using a mixture of indexed terms and title, abstract and keywords. The search included terms: obese, surgical weight loss intervention, colorectal cancer, and colorectal adenomas. Studies that included bariatric intervention patient's vs non-surgical obese patients younger than 50years were considered. Inclusion criteria were patients with BMI more than 35kg/m2 who underwent a colonoscopy. Studies with follow-up colonoscopy performed in less than 4years after bariatric surgery and those that evaluated patients with a mean age difference of 5 or more years between groups were excluded. Outcomes analyzed in obese patients with surgical treatment vs control patients included colorectal cancer incidence. From 2008 to 2021, a total of 1536 records were identified. Five retrospective studies that included 48,916 patients were analyzed. Follow-up period ranged from 5 to 22.2years. 20,663 (42.24%) patients underwent bariatric surgery and 28,253 (57.76%) were part of the control patients. Roux-en-Y gastric bypass was performed in 14,400 (69.7%) individuals. The intervention and control group were similar in age range, proportion of female participants and initial body mass index (35-48.3 vs 35-49.3, respectively). 126/20663 (0.61%) patients in the bariatric surgery group and 175/28253 (0.62%) individuals in the control group presented CRC. In this meta-analysis, we were unable to demonstrate a significant impact of the Bariatric Surgery on EOCRC risk. Prospective trials with longer follow-up periods should be done to prove the colorectal cancer risk reduction.

Does drinking coffee reduce the risk of colorectal cancer? A qualitative umbrella review of systematic reviews.

Coffee drinking has been linked to many positive health effects, including reduced risk of some cancers. The present study aimed to provide an overview of the collective evidence on the association between coffee consumption and risk of colorectal cancer (CRC) through an umbrella review of the published systematic reviews. This PRISMA-compliant systematic review of systematic reviews assessed the association between coffee drinking and the risk of CRC. An umbrella review approach was followed in a qualitative narrative manner. The quality of included reviews was assessed by the AMSTAR2 checklist. The main outcome was the association between coffee drinking and CRC and colon and rectal cancer separately. Fourteen systematic reviews were included in this umbrella review. Coffee drinking was associated with a significant reduction in the risk of CRC according to five reviews (11-24%), colon cancer according to two reviews (9-21%), and rectal cancer according to one review (25%). One review reported a significant risk reduction of CRC by 7% with drinking six or more cups of coffee per day and another review reported a significant risk reduction of 8% with fivecups per day reaching 12% with sixcups per day. Decaffeinated coffee was associated with a significant risk reduction according to three reviews. The evidence supporting caffeinated coffee as associated with a reduced risk of CRC is inconsistent. Dose-dependent relation analysis suggests that the protective effect of coffee drinking against CRC is evident with the consumption of five or more cups per day.