Associations between low- and high-fat dairy intake and recurrence risk in people with stage I-III colorectal cancer differ by sex and primary tumour location.

We previously demonstrated that intake of low-fat dairy, but not high-fat dairy, was associated with a decreased colorectal cancer (CRC) recurrence risk. These risks, however, may differ by sex, primary tumour location, and disease stage. Combining data from two similar prospective cohort studies of people with stage I-III CRC enabled these subgroup analyses. Participants completed a food frequency questionnaire at diagnosis (n = 2283). We examined associations between low- and high-fat dairy intake and recurrence risk using multivariable Cox proportional hazard models, stratified by sex, and primary tumour location (colon and rectum), and disease stage (I/II and III). Upper quartiles were compared to lower quartiles of intake, and recurrence was defined as a locoregional recurrence and/or metastasis. During a median follow-up of 5.0 years, 331 recurrences were detected. A higher intake of low-fat dairy was associated with a reduced risk of recurrence (hazard ratio [HR]: 0.60, 95% confidence interval [CI]: 0.43-0.83), which seemed more pronounced in men (HR: 0.51, 95% CI: 0.34-0.77) than in women (HR: 0.84, 95% CI: 0.47-1.49). A higher intake of high-fat dairy was associated with an increased risk of recurrence in participants with colon cancer (HR: 1.60, 95% CI: 1.03-2.50), but not rectal cancer (HR: 0.88, 95% CI: 0.54-1.45). No differences in associations were observed between strata of disease stage. Concluding, our findings imply that dietary advice regarding low-fat dairy intake may be especially important for men with CRC, and that dietary advice regarding high-fat dairy intake may be specifically important in people with colon cancer.

Coffee consumption is associated with a reduced risk of colorectal cancer recurrence and all-cause mortality.

Coffee consumption has been associated with a reduced risk of developing colorectal cancer (CRC). However, it is not clear whether coffee consumption is related to CRC progression. Hence, we assessed the association of coffee consumption with CRC recurrence and all-cause mortality using data from a prospective cohort study of 1719 stage I-III CRC patients in the Netherlands. Coffee consumption and other lifestyle characteristics were self-reported using questionnaires at the time of diagnosis. We retrieved recurrence and all-cause mortality data from the Netherlands Cancer Registry and the Personal Records Database, respectively. Cox proportional hazard regression models with and without restricted cubic splines were used to calculate hazard ratios (HR) and 95% confidence intervals (CI) adjusted for age, sex, education, smoking status, cancer stage and tumor location. We observed 257 recurrences during a 6.2-year median follow-up and 309 deaths during a 6.6-year median follow-up. Consuming more than 4 cups/d of coffee compared to an intake of <2 cups/d was associated with a 32% lower risk of CRC recurrence (95% CI: 0.49, 0.94,). The association between coffee consumption and all-cause mortality was U-shaped; coffee intake seemed optimal at 3-5 cups/d with the lowest risk at 4 cups/d (HR: 0.68, 95% CI: 0.53, 0.88). Our results suggest that coffee consumption may be associated with a lower risk of CRC recurrence and all-cause mortality. The association between coffee consumption and all-cause mortality appeared nonlinear. More studies are needed to understand the mechanism by which coffee consumption might improve CRC prognosis.

Hematocrit Is Associated with Cancer-Related Fatigue in Colorectal Cancer Survivors: A Longitudinal Analysis.

BACKGROUND: Cancer-related fatigue (CRF) is a frequent symptom in colorectal cancer survivors. It is unknown to what extent anemia may contribute to CRF in colorectal cancer survivors. This study aimed to investigate the association between hematocrit, as marker for anemia, and CRF among colorectal cancer survivors from diagnosis until two years thereafter. METHODS: The study population included 1,506 newly diagnosed colorectal cancer survivors at any stage of disease from a prospective cohort study. Hematocrit and CRF (EORTC QLQ-C30) were assessed at diagnosis, six months, and two years after diagnosis. Multivariable logistic regression or multivariable linear mixed models were used to assess the associations of hematocrit with CRF prevalence, or CRF severity over time, respectively. RESULTS: A low hematocrit (levels <40% men/<36% women) was present in a third of the survivors at diagnosis and six months thereafter, and among 16% two years after diagnosis. The prevalence of CRF was 15% at diagnosis, peaked at 27% at six months, and was 14% two years after diagnosis. Hematocrit was associated with the prevalence of CRF at diagnosis [OR, 0.92; confidence interval (CI), 0.88-0.95], 6 months (OR, 0.89; 95% CI, 0.86-0.92), and 2 years (OR, 0.91; CI, 0.87-0.96) after diagnosis. Lower hematocrit was associated with higher severity of CRF over time (beta-coefficient = 1.3; CI, 1.5-1.1). CONCLUSIONS: Lower hematocrit levels were longitudinally associated with a higher prevalence and severity of CRF in colorectal cancer. IMPACT: Our findings emphasize the importance of long-term anemia monitoring and a potential role of anemia in CRF among colorectal cancer survivors.

Allometric versus traditional body-shape indices and risk of colorectal cancer: a Mendelian randomization analysis.

BACKGROUND: Traditional body-shape indices such as Waist Circumference (WC), Hip Circumference (HC), and Waist-to-Hip Ratio (WHR) are associated with colorectal cancer (CRC) risk, but are correlated with Body Mass Index (BMI), and adjustment for BMI introduces a strong correlation with height. Thus, new allometric indices have been developed, namely A Body Shape Index (ABSI), Hip Index (HI), and Waist-to-Hip Index (WHI), which are uncorrelated with weight and height; these have also been associated with CRC risk in observational studies, but information from Mendelian randomization (MR) studies is missing. METHODS: We used two-sample MR to examine potential causal cancer site- and sex-specific associations of the genetically-predicted allometric body-shape indices with CRC risk, and compared them with BMI-adjusted traditional body-shape indices, and BMI. Data were obtained from UK Biobank and the GIANT consortium, and from GECCO, CORECT and CCFR consortia. RESULTS: WHI was positively associated with CRC in men (OR per SD: 1.20, 95% CI: 1.03-1.39) and in women (1.15, 1.06-1.24), and similarly for colon and rectal cancer. ABSI was positively associated with colon and rectal cancer in men (1.27, 1.03-1.57; and 1.40, 1.10-1.77, respectively), and with colon cancer in women (1.20, 1.07-1.35). There was little evidence for association between HI and colon or rectal cancer. The BMI-adjusted WHR and HC showed similar associations to WHI and HI, whereas WC showed similar associations to ABSI only in women. CONCLUSIONS: This large MR study provides strong evidence for a potential causal positive association of the allometric indices ABSI and WHI with CRC in both sexes, thus establishing the association between abdominal fat and CRC without the limitations of the traditional waist size indices and independently of BMI. Among the BMI-adjusted traditional indices, WHR and HC provided equivalent associations with WHI and HI, while differences were observed between WC and ABSI.

Determinants of Physical Activity among Patients with Colorectal Cancer: From Diagnosis to 5 Years after Diagnosis.

INTRODUCTION: Physical activity (PA) is associated with higher quality of life and probably better prognosis among colorectal cancer (CRC) patients. This study focuses on determinants of PA among CRC patients from diagnosis until 5 yr postdiagnosis. METHODS: Sociodemographic and disease-related factors of participants of two large CRC cohort studies were combined. Moderate-to-vigorous PA during sport and leisure time (MVPA-SL) was measured at diagnosis (T0) and 6, 12, 24, and 60 months (T6 to T60) postdiagnosis, using the SQUASH questionnaire. Mixed-effects models were performed to identify sociodemographic and disease-related determinants of MVPA-SL, separately for stage I-III colon (CC), stage I-III rectal cancer (RC), and stage IV CRC (T0 and T6 only). Associations were defined as consistently present when significant at ≥4 timepoints for the stage I-III subsets. MVPA-SL levels were compared with an age- and sex-matched sample of the general Dutch population. RESULTS: In total, 2905 CC, 1459 RC and 436 stage IV CRC patients were included. Patients with higher fatigue scores, and women compared with men had consistently lower MVPA-SL levels over time, regardless of tumor type and stage. At T6, having a stoma was significantly associated with lower MVPA-SL among stage I-III RC patients. Systemic therapy and radiotherapy were not significantly associated with MVPA-SL changes at T6. Compared with the general population, MVPA-SL levels of CRC patients were lower at all timepoints, most notably at T6. CONCLUSIONS: Female sex and higher fatigue scores were consistent determinants of lower MVPA-SL levels among all CRC patients, and MVPA-SL levels were lowest at 6 months postdiagnosis. Our results can inform the design of intervention studies aimed at improving PA, and guide healthcare professionals in optimizing individualized support.

Genome-Wide Gene-Environment Interaction Analyses to Understand the Relationship between Red Meat and Processed Meat Intake and Colorectal Cancer Risk.

BACKGROUND: High red meat and/or processed meat consumption are established colorectal cancer risk factors. We conducted a genome-wide gene-environment (GxE) interaction analysis to identify genetic variants that may modify these associations. METHODS: A pooled sample of 29,842 colorectal cancer cases and 39,635 controls of European ancestry from 27 studies were included. Quantiles for red meat and processed meat intake were constructed from harmonized questionnaire data. Genotyping arrays were imputed to the Haplotype Reference Consortium. Two-step EDGE and joint tests of GxE interaction were utilized in our genome-wide scan. RESULTS: Meta-analyses confirmed positive associations between increased consumption of red meat and processed meat with colorectal cancer risk [per quartile red meat OR = 1.30; 95% confidence interval (CI) = 1.21-1.41; processed meat OR = 1.40; 95% CI = 1.20-1.63]. Two significant genome-wide GxE interactions for red meat consumption were found. Joint GxE tests revealed the rs4871179 SNP in chromosome 8 (downstream of HAS2); greater than median of consumption ORs = 1.38 (95% CI = 1.29-1.46), 1.20 (95% CI = 1.12-1.27), and 1.07 (95% CI = 0.95-1.19) for CC, CG, and GG, respectively. The two-step EDGE method identified the rs35352860 SNP in chromosome 18 (SMAD7 intron); greater than median of consumption ORs = 1.18 (95% CI = 1.11-1.24), 1.35 (95% CI = 1.26-1.44), and 1.46 (95% CI = 1.26-1.69) for CC, CT, and TT, respectively. CONCLUSIONS: We propose two novel biomarkers that support the role of meat consumption with an increased risk of colorectal cancer. IMPACT: The reported GxE interactions may explain the increased risk of colorectal cancer in certain population subgroups.

Combining Asian and European genome-wide association studies of colorectal cancer improves risk prediction across racial and ethnic populations.

Polygenic risk scores (PRS) have great potential to guide precision colorectal cancer (CRC) prevention by identifying those at higher risk to undertake targeted screening. However, current PRS using European ancestry data have sub-optimal performance in non-European ancestry populations, limiting their utility among these populations. Towards addressing this deficiency, we expand PRS development for CRC by incorporating Asian ancestry data (21,731 cases; 47,444 controls) into European ancestry training datasets (78,473 cases; 107,143 controls). The AUC estimates (95% CI) of PRS are 0.63(0.62-0.64), 0.59(0.57-0.61), 0.62(0.60-0.63), and 0.65(0.63-0.66) in independent datasets including 1681-3651 cases and 8696-115,105 controls of Asian, Black/African American, Latinx/Hispanic, and non-Hispanic White, respectively. They are significantly better than the European-centric PRS in all four major US racial and ethnic groups (p-values < 0.05). Further inclusion of non-European ancestry populations, especially Black/African American and Latinx/Hispanic, is needed to improve the risk prediction and enhance equity in applying PRS in clinical practice.

Pre- and post-diagnostic dairy intake in relation to recurrence and all-cause mortality in people with stage I-III colorectal cancer.

PURPOSE: Higher dairy consumption is associated with a lower risk of colorectal cancer (CRC), but no studies thus far have investigated its relation with recurrence in CRC. Few studies have investigated total dairy in relation to mortality in CRC, and yielded inconsistent results. METHODS: In this prospective cohort study, people newly diagnosed with stage I-III CRC filled out a food frequency questionnaire at diagnosis (n = 1812) and six months after diagnosis (n = 1672). We examined associations between pre- and post-diagnostic intake of total dairy, low-fat dairy, high-fat dairy, milk, yoghurt, and cheese with recurrence and all-cause mortality using multivariable Cox proportional hazard models and restricted cubic splines (RCS). RESULTS: A total of 176 recurrences and 301 deaths occurred during a median follow-up of 3.0 and 5.9 years, respectively. Before diagnosis, a higher low-fat dairy intake was associated with a lower risk of recurrence (HRQ4vsQ1: 0.42, 95% CI 0.26-0.67; PRCS: 0.008) and all-cause mortality (HRQ4vsQ1: 0.58, 95% CI 0.41-0.81; PRCS < 0.001), whereas a higher high-fat dairy consumption tended to be associated with an increased all-cause mortality risk (HRQ4vsQ1: 1.41, 95% CI 0.98-2.01; PRCS: 0.030). After diagnosis, only the associations between low- and high-fat dairy in relation to all-cause mortality remained. CONCLUSIONS: This study demonstrated that higher pre- and post-diagnostic intakes of low-fat dairy were associated with a reduced all-cause mortality risk in people with stage I-III CRC, whereas higher intakes of high-fat dairy were associated with an increased all-cause mortality risk. Also, a higher pre-diagnostic low-fat dairy intake was associated with a reduced risk of recurrence. TRIAL REGISTRATION: Clinical Trials.gov identifier: NCT03191110.

Higher Plasma Creatinine Is Associated with an Increased Risk of Death in Patients with Non-Metastatic Rectal but Not Colon Cancer: Results from an International Cohort Consortium.

Colorectal cancer (CRC) is increasingly recognized as a heterogeneous disease. No studies have prospectively examined associations of blood metabolite concentrations with all-cause mortality in patients with colon and rectal cancer separately. Targeted metabolomics (Biocrates AbsoluteIDQ p180) and pathway analyses (MetaboAnalyst 4.0) were performed on pre-surgery collected plasma from 674 patients with non-metastasized (stage I-III) colon (n = 394) or rectal cancer (n = 283). Metabolomics data and covariate information were received from the international cohort consortium MetaboCCC. Cox proportional hazards models were computed to investigate associations of 148 metabolite levels with all-cause mortality adjusted for age, sex, tumor stage, tumor site (whenever applicable), and cohort; the false discovery rate (FDR) was used to account for multiple testing. A total of 93 patients (14%) were deceased after an average follow-up time of 4.4 years (60 patients with colon cancer and 33 patients with rectal cancer). After FDR adjustment, higher plasma creatinine was associated with a 39% increase in all-cause mortality in patients with rectal cancer. HR: 1.39, 95% CI 1.23-1.72, pFDR = 0.03; but not colon cancer: pFDR = 0.96. Creatinine is a breakdown product of creatine phosphate in muscle and may reflect changes in skeletal muscle mass. The starch and sucrose metabolisms were associated with increased all-cause mortality in colon cancer but not in rectal cancer. Genes in the starch and sucrose metabolism pathways were previously linked to worse clinical outcomes in CRC. In summary, our findings support the hypothesis that colon and rectal cancer have different etiological and clinical outcomes that need to be considered for targeted treatments.

The association between anastomotic leakage and health-related quality of life after colorectal cancer surgery.

AIM: Colorectal anastomotic leakage (AL) is a serious complication. Studies on the impact of AL on health-related quality of life (HRQoL) are scarce. We aimed to investigate the association between AL and HRQoL in colorectal cancer patients up to 2 years after diagnosis, and to evaluate whether AL is associated with a clinically relevant decrease in HRQoL over time. METHODS: Patients diagnosed with Stage I-III colorectal cancer undergoing elective surgical resection with primary anastomosis between 2010 and 2017 were included. HRQoL was evaluated using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30, represented by the summary score, and analysed at diagnosis and at 6 months and 2 years post-diagnosis. Multivariable linear regression was performed to assess the association between AL and HRQoL, while multivariable logistic regression was used to investigate the association between AL and a clinically relevant HRQoL decrease (≥10 points) during follow-up compared to the time of diagnosis. RESULTS: In total, 1197 patients were included of whom 63 (5%) developed AL. AL was not associated with HRQoL at 6 months post-diagnosis nor at 2 years post-diagnosis. However, having AL was associated with an increased risk of a clinically relevant decrease in HRQoL at 6 months post-diagnosis (OR 3.65, 95% CI 1.62-8.21) but not at 2 years after diagnosis (OR 1.91, 95% CI 0.62-5.93). CONCLUSION: Although AL was not associated with HRQoL at 6 months or 2 years post-diagnosis, AL was a determinant of a clinically relevant decrease in HRQoL at 6 months after diagnosis. Future work should identify feasible and effective strategies to prevent declines in QoL in this patient population.

External validation and updating of prediction models for estimating the 1-year risk of low health-related quality of life in colorectal cancer survivors.

OBJECTIVES: Timely identification of colorectal cancer (CRC) survivors at risk of experiencing low health-related quality of life (HRQoL) in the near future is important for enabling appropriately tailored preventive actions. We previously developed and internally validated risk prediction models to estimate the 1-year risk of low HRQoL in long-term CRC survivors. In this article, we aim to externally validate and update these models in a population of short-term CRC survivors. STUDY DESIGN AND SETTING: In a pooled cohort of 1,596 CRC survivors, seven HRQoL domains (global QoL, cognitive/emotional/physical/role/social functioning, and fatigue) were measured prospectively at approximately 5 months postdiagnosis (baseline for prediction) and approximately 1 year later by a validated patient-reported outcome measure (European Organization for Research and Treatment of Cancer Quality of life Questionnaire-Core 30). For each HRQoL domain, 1-year scores were dichotomized into low vs. normal/high HRQoL. Performance of the previously developed multivariable logistic prediction models was evaluated (calibration and discrimination). Models were updated to create a more parsimonious predictor set for all HRQoL domains. RESULTS: Updated models showed good calibration and discrimination (AUC ≥0.75), containing a single set of 15 predictors, including nonmodifiable (age, sex, education, time since diagnosis, chemotherapy, radiotherapy, stoma, and comorbidities) and modifiable predictors (body mass index, physical activity, smoking, anxiety/depression, and baseline fatigue and HRQoL domain scores). CONCLUSION: Externally validated and updated prediction models performed well for estimating the 1-year risk of low HRQoL in CRC survivors within 6 months postdiagnosis. The impact of implementing the models in oncology practice to improve HRQoL outcomes in CRC survivors needs to be evaluated.

Longitudinal Associations between Inflammatory Markers and Fatigue up to Two Years after Colorectal Cancer Treatment.

BACKGROUND: Fatigue is often reported by colorectal cancer survivors and largely impacts their quality of life. Inflammation has been linked to fatigue mainly in patients with breast cancer. Therefore, we investigated how inflammation is longitudinally associated with fatigue in colorectal cancer survivors, up to 2 years posttreatment. METHODS: A total of 257 patients from the ongoing Energy for life after ColoRectal cancer cohort study were included in the analysis. Plasma levels of IL6, IL8, IL10, TNFα, high-sensitivity C-reactive protein (hsCRP), and fatigue were measured at 6 weeks, 6, 12, and 24 months posttreatment. Fatigue was measured through the validated Checklist Individual Strength (CIS; total, 20-140), consisting of four subscales - subjective fatigue (8-56), motivation (4-28), physical activity (3-21), and concentration (5-35), and the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 fatigue subscale (0-100). Linear mixed-models were used to assess the confounder-adjusted longitudinal associations between inflammatory markers and overall fatigue along with the subscales. RESULTS: Mean levels of CIS fatigue decreased from 62.9 at 6 weeks to 53.0 at 24 months. In general, levels of inflammatory markers also decreased over time. No statistically significant longitudinal associations were found between IL6, IL8, IL10, TNFα, and fatigue. Higher levels of hsCRP were associated with more CIS fatigue (ß per SD 3.21, 95% confidence interval (CI), 1.42-5.01) and EORTC fatigue (ß 2.41, 95% CI, 0.72-4.10). CONCLUSIONS: Increased levels of hsCRP are longitudinally associated with more posttreatment fatigue in colorectal cancer survivors. IMPACT: These findings suggest that low-grade inflammation may play a role in fatigue reported by colorectal cancer survivors up to 2 years posttreatment.

Genome-Wide Interaction Analysis of Genetic Variants With Menopausal Hormone Therapy for Colorectal Cancer Risk.

BACKGROUND: The use of menopausal hormone therapy (MHT) may interact with genetic variants to influence colorectal cancer (CRC) risk. METHODS: We conducted a genome-wide, gene-environment interaction between single nucleotide polymorphisms and the use of any MHT, estrogen only, and combined estrogen-progestogen therapy with CRC risk, among 28 486 postmenopausal women (11 519 CRC patients and 16 967 participants without CRC) from 38 studies, using logistic regression, 2-step method, and 2- or 3-degree-of-freedom joint test. A set-based score test was applied for rare genetic variants. RESULTS: The use of any MHT, estrogen only and estrogen-progestogen were associated with a reduced CRC risk (odds ratio [OR] = 0.71, 95% confidence interval [CI] = 0.64 to 0.78; OR = 0.65, 95% CI = 0.53 to 0.79; and OR = 0.73, 95% CI = 0.59 to 0.90, respectively). The 2-step method identified a statistically significant interaction between a GRIN2B variant rs117868593 and MHT use, whereby MHT-associated CRC risk was statistically significantly reduced in women with the GG genotype (OR = 0.68, 95% CI = 0.64 to 0.72) but not within strata of GC or CC genotypes. A statistically significant interaction between a DCBLD1 intronic variant at 6q22.1 (rs10782186) and MHT use was identified by the 2-degree-of-freedom joint test. The MHT-associated CRC risk was reduced with increasing number of rs10782186-C alleles, showing odds ratios of 0.78 (95% CI = 0.70 to 0.87) for TT, 0.68 (95% CI = 0.63 to 0.73) for TC, and 0.66 (95% CI = 0.60 to 0.74) for CC genotypes. In addition, 5 genes in rare variant analysis showed suggestive interactions with MHT (2-sided P < 1.2 × 10-4). CONCLUSION: Genetic variants that modify the association between MHT and CRC risk were identified, offering new insights into pathways of CRC carcinogenesis and potential mechanisms involved.

Higher vitamin B6 status is associated with improved survival among patients with stage I-III colorectal cancer.

BACKGROUND: Folate-mediated 1-carbon metabolism requires several nutrients, including vitamin B6. Circulating biomarker concentrations indicating high vitamin B6 status are associated with a reduced risk of colorectal cancer (CRC). However, little is known about the effect of B6 status in relation to clinical outcomes in CRC patients. OBJECTIVES: We investigated survival outcomes in relation to vitamin B6 status in prospectively followed CRC patients. METHODS: A total of 2031 patients with stage I-III CRC participated in 6 prospective patient cohorts in the international FOCUS (folate-dependent 1-carbon metabolism in colorectal cancer recurrence and survival) Consortium. Preoperative blood samples were used to measure vitamin B6 status by the direct marker pyridoxal 5'-phosphate (PLP), as well as the functional marker HK-ratio (HKr)[3'-hydroxykynurenine: (kynurenic acid + xanthurenic acid + 3'-hydroxy anthranilic acid + anthranilic acid)]. Using Cox proportional hazards regression, we examined associations of vitamin B6 status with overall survival (OS), disease-free survival (DFS), and risk of recurrence, adjusted for patient age, sex, circulating creatinine concentrations, tumor site, stage, and cohort. RESULTS: After a median follow-up of 3.2 y for OS, higher preoperative vitamin B6 status as assessed by PLP and the functional marker HKr was associated with 16-32% higher all-cause and disease-free survival, although there was no significant association with disease recurrence (doubling in PLP concentration: HROS, 0.68; 95% CI: 0.59, 0.79; HRDFS, 0.84; 95% CI: 0.75, 0.94; HRRecurrence, 0.96; 95% CI: 0.84, 1.09; HKr: HROS, 2.04; 95% CI: 1.67, 2.49; HRDFS, 1.56; 95% CI: 1.31, 1.85; HRRecurrence, 1.21; 95% CI: 0.96,1. 52). The association of PLP with improved OS was consistent across colorectal tumor site (right-sided colon: HROS, 0.75; 95% CI: 0.59, 0.96; left-sided colon: HROS, 0.71; 95% CI: 0.55, 0.92; rectosigmoid junction and rectum: HROS, 0.61; 95% CI: 0.47, 0.78). CONCLUSION: Higher preoperative vitamin B6 status is associated with improved OS among stage I-III CRC patients.

Large-scale Integrated Analysis of Genetics and Metabolomic Data Reveals Potential Links Between Lipids and Colorectal Cancer Risk.

BACKGROUND: The etiology of colorectal cancer is not fully understood. METHODS: Using genetic variants and metabolomics data including 217 metabolites from the Framingham Heart Study (n = 1,357), we built genetic prediction models for circulating metabolites. Models with prediction R2 > 0.01 (Nmetabolite = 58) were applied to predict levels of metabolites in two large consortia with a combined sample size of approximately 46,300 cases and 59,200 controls of European and approximately 21,700 cases and 47,400 controls of East Asian (EA) descent. Genetically predicted levels of metabolites were evaluated for their associations with colorectal cancer risk in logistic regressions within each racial group, after which the results were combined by meta-analysis. RESULTS: Of the 58 metabolites tested, 24 metabolites were significantly associated with colorectal cancer risk [Benjamini-Hochberg FDR (BH-FDR) < 0.05] in the European population (ORs ranged from 0.91 to 1.06; P values ranged from 0.02 to 6.4 × 10-8). Twenty one of the 24 associations were replicated in the EA population (ORs ranged from 0.26 to 1.69, BH-FDR < 0.05). In addition, the genetically predicted levels of C16:0 cholesteryl ester was significantly associated with colorectal cancer risk in the EA population only (OREA: 1.94, 95% CI, 1.60-2.36, P = 2.6 × 10-11; OREUR: 1.01, 95% CI, 0.99-1.04, P = 0.3). Nineteen of the 25 metabolites were glycerophospholipids and triacylglycerols (TAG). Eighteen associations exhibited significant heterogeneity between the two racial groups (PEUR-EA-Het < 0.005), which were more strongly associated in the EA population. This integrative study suggested a potential role of lipids, especially certain glycerophospholipids and TAGs, in the etiology of colorectal cancer. CONCLUSIONS: This study identified potential novel risk biomarkers for colorectal cancer by integrating genetics and circulating metabolomics data. IMPACT: The identified metabolites could be developed into new tools for risk assessment of colorectal cancer in both European and EA populations.

Longitudinal Associations of Adherence to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Lifestyle Recommendations with Quality of Life and Symptoms in Colorectal Cancer Survivors up to 24 Months Post-Treatment.

Post-treatment adherence to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) lifestyle recommendations were associated with health-related quality of life (HRQoL), fatigue, and chemotherapy-induced peripheral neuropathy (CIPN) in colorectal cancer (CRC) survivors. In a prospective cohort among CRC survivors (n = 459), repeated home-visits were performed at 6 weeks, 6, 12, and 24 months post-treatment. Dietary intake, body composition, sedentary behaviour, and physical activity were assessed to construct a lifestyle score based on adherence to seven 2018 WCRF/AICR recommendations. Longitudinal associations of the lifestyle score with HRQoL, fatigue, and CIPN were analysed by confounder-adjusted linear mixed models. A higher lifestyle score was associated with better physical functioning and less activity-related fatigue, but not with CIPN. Adjustment for physical activity substantially attenuated observed associations, indicating its importance in the lifestyle score with regards to HRQoL. In contrast, adjustment for body composition and alcohol inflated observed associations, indicating that both recommendations had a counteractive influence within the lifestyle score. Our findings suggest that CRC survivors benefit from an overall adherence to the WCRF/AICR lifestyle recommendations in terms of HRQoL and fatigue, but not CIPN. Specific recommendations have a varying influence on these associations, complicating the interpretation and requiring further study.

Associations Between Glycemic Traits and Colorectal Cancer: A Mendelian Randomization Analysis.

BACKGROUND: Glycemic traits-such as hyperinsulinemia, hyperglycemia, and type 2 diabetes-have been associated with higher colorectal cancer risk in observational studies; however, causality of these associations is uncertain. We used Mendelian randomization (MR) to estimate the causal effects of fasting insulin, 2-hour glucose, fasting glucose, glycated hemoglobin (HbA1c), and type 2 diabetes with colorectal cancer. METHODS: Genome-wide association study summary data were used to identify genetic variants associated with circulating levels of fasting insulin (n = 34), 2-hour glucose (n = 13), fasting glucose (n = 70), HbA1c (n = 221), and type 2 diabetes (n = 268). Using 2-sample MR, we examined these variants in relation to colorectal cancer risk (48 214 case patient and 64 159 control patients). RESULTS: In inverse-variance models, higher fasting insulin levels increased colorectal cancer risk (odds ratio [OR] per 1-SD = 1.65, 95% confidence interval [CI] = 1.15 to 2.36). We found no evidence of any effect of 2-hour glucose (OR per 1-SD = 1.02, 95% CI = 0.86 to 1.21) or fasting glucose (OR per 1-SD = 1.04, 95% CI = 0.88 to 1.23) concentrations on colorectal cancer risk. Genetic liability to type 2 diabetes (OR per 1-unit increase in log odds = 1.04, 95% CI = 1.01 to 1.07) and higher HbA1c levels (OR per 1-SD = 1.09, 95% CI = 1.00 to 1.19) increased colorectal cancer risk, although these findings may have been biased by pleiotropy. Higher HbA1c concentrations increased rectal cancer risk in men (OR per 1-SD = 1.21, 95% CI = 1.05 to 1.40), but not in women. CONCLUSIONS: Our results support a causal effect of higher fasting insulin, but not glucose traits or type 2 diabetes, on increased colorectal cancer risk. This suggests that pharmacological or lifestyle interventions that lower circulating insulin levels may be beneficial in preventing colorectal tumorigenesis.

Longitudinal associations of fiber, vegetable, and fruit intake with quality of life and fatigue in colorectal cancer survivors up to 24 months posttreatment.

BACKGROUND: The increasing colorectal cancer (CRC) survivor population highlights the need for dietary recommendations in order to enhance health-related quality of life (HRQoL) and alleviate symptoms of fatigue, chemotherapy-induced peripheral neuropathy (CIPN), and gastrointestinal problems. OBJECTIVES: Because of the therapeutic potential of dietary fiber on the gut, we aim to assess longitudinal associations of postdiagnostic dietary fiber, fruit, and vegetable intake, a major source of dietary fiber, with HRQoL, fatigue, CIPN, and gastrointestinal symptoms in CRC survivors from 6 wk to 24 mo posttreatment. METHODS: In a prospective cohort among stage I-III CRC survivors (n = 459), 5 repeated study measurements between diagnosis and 24 mo posttreatment were executed. Dietary fiber intake and fruit and vegetable intake were measured by 7-d dietary records. HRQoL, fatigue, CIPN, and gastrointestinal symptoms were measured by validated questionnaires. We applied confounder-adjusted linear mixed models to analyze longitudinal associations from 6 wk until 24 mo posttreatment and used hybrid models to disentangle the overall association into intraindividual changes and interindividual differences over time. RESULTS: Higher dietary fiber intake and fruit and vegetable intake were longitudinally associated with statistically significant better physical functioning and less fatigue. Intraindividual analyses showed that an increase of 10 g/d in dietary fiber within individuals over time was associated with better physical functioning (ß: 2.3; 95% CI: 0.1, 4.4), role functioning (ability to perform daily activities; 5.9; 1.5, 10.3), and less fatigue (-4.1; -7.7, -0.5). An average increase in fruit and vegetable intake of 100 g/d between individuals over time was predominantly associated with less fatigue (-2.2; -4.2, -0.3). No associations were found with CIPN and gastrointestinal symptoms. CONCLUSIONS: Our results suggest that increasing dietary fiber, fruit, and vegetable intake is related to better physical and role functioning and less fatigue in the first 2 y after the end of treatment for CRC.

Identification of Lifestyle Behaviors Associated with Recurrence and Survival in Colorectal Cancer Patients Using Random Survival Forests.

Current lifestyle recommendations for cancer survivors are the same as those for the general public to decrease their risk of cancer. However, it is unclear which lifestyle behaviors are most important for prognosis. We aimed to identify which lifestyle behaviors were most important regarding colorectal cancer (CRC) recurrence and all-cause mortality with a data-driven method. The study consisted of 1180 newly diagnosed stage I-III CRC patients from a prospective cohort study. Lifestyle behaviors included in the current recommendations, as well as additional lifestyle behaviors related to diet, physical activity, adiposity, alcohol use, and smoking were assessed six months after diagnosis. These behaviors were simultaneously analyzed as potential predictors of recurrence or all-cause mortality with Random Survival Forests (RSFs). We observed 148 recurrences during 2.6-year median follow-up and 152 deaths during 4.8-year median follow-up. Higher intakes of sugary drinks were associated with increased recurrence risk. For all-cause mortality, fruit and vegetable, liquid fat and oil, and animal protein intake were identified as the most important lifestyle behaviors. These behaviors showed non-linear associations with all-cause mortality. Our exploratory RSF findings give new ideas on potential associations between certain lifestyle behaviors and CRC prognosis that still need to be confirmed in other cohorts of CRC survivors.