Genome-wide interaction analysis of folate for colorectal cancer risk.

BACKGROUND: Epidemiological and experimental evidence suggests that higher folate intake is associated with decreased colorectal cancer (CRC) risk; however, the mechanisms underlying this relationship are not fully understood. Genetic variation that may have a direct or indirect impact on folate metabolism can provide insights into folate's role in CRC. OBJECTIVES: Our aim was to perform a genome-wide interaction analysis to identify genetic variants that may modify the association of folate on CRC risk. METHODS: We applied traditional case-control logistic regression, joint 3-degree of freedom, and a 2-step weighted hypothesis approach to test the interactions of common variants (allele frequency >1%) across the genome and dietary folate, folic acid supplement use, and total folate in relation to risk of CRC in 30,550 cases and 42,336 controls from 51 studies from 3 genetic consortia (CCFR, CORECT, GECCO). RESULTS: Inverse associations of dietary, total folate, and folic acid supplement with CRC were found (odds ratio [OR]: 0.93; 95% confidence interval [CI]: 0.90, 0.96; and 0.91; 95% CI: 0.89, 0.94 per quartile higher intake, and 0.82 (95% CI: 0.78, 0.88) for users compared with nonusers, respectively). Interactions (P-interaction < 5×10-8) of folic acid supplement and variants in the 3p25.2 locus (in the region of Synapsin II [SYN2]/tissue inhibitor of metalloproteinase 4 [TIMP4]) were found using traditional interaction analysis, with variant rs150924902 (located upstream to SYN2) showing the strongest interaction. In stratified analyses by rs150924902 genotypes, folate supplementation was associated with decreased CRC risk among those carrying the TT genotype (OR: 0.82; 95% CI: 0.79, 0.86) but increased CRC risk among those carrying the TA genotype (OR: 1.63; 95% CI: 1.29, 2.05), suggesting a qualitative interaction (P-interaction = 1.4×10-8). No interactions were observed for dietary and total folate. CONCLUSIONS: Variation in 3p25.2 locus may modify the association of folate supplement with CRC risk. Experimental studies and studies incorporating other relevant omics data are warranted to validate this finding.

Risk of Colorectal Cancer and Colorectal Cancer Mortality Beginning One Year after a Negative Fecal Occult Blood Test, among Screen-Eligible 76- to 85-Year-Olds.

BACKGROUND: Colorectal cancer screening is universally recommended for adults ages 45 to 75 years. Noninvasive fecal occult blood tests are effective screening tests recommended by guidelines. However, empirical evidence to inform older adults' decisions about whether to continue screening is sparse, especially for individuals with prior screening. METHODS: This study used a retrospective cohort of older adults at three Kaiser Permanente integrated healthcare systems (Northern California, Southern California, Washington) and Parkland Health. Beginning 1 year following a negative stool-based screening test, cumulative risks of colorectal cancer incidence, colorectal cancer mortality (accounting for deaths from other causes), and non-colorectal cancer mortality were estimated. RESULTS: Cumulative incidence of colorectal cancer in screen-eligible adults ages 76 to 85 with a negative fecal occult blood test 1 year ago (N = 118,269) was 0.23% [95% confidence interval (CI), 0.20%-0.26%] after 2 years and 1.21% (95% CI, 1.13%-1.30%) after 8 years. Cumulative colorectal cancer mortality was 0.03% (95% CI, 0.02%-0.04%) after 2 years and 0.33% (95% CI, 0.28%-0.39%) after 8 years. Cumulative risk of death from non-colorectal cancer causes was 4.81% (95% CI, 4.68%-4.96%) after 2 years and 28.40% (95% CI, 27.95%-28.85%) after 8 years. CONCLUSIONS: Among 76- to 85-year-olds with a recent negative stool-based test, cumulative colorectal cancer incidence and mortality estimates were low, especially within 2 years; death from other causes was over 100 times more likely than death from colorectal cancer. IMPACT: These findings of low absolute colorectal cancer risk, and comparatively higher risk of death from other causes, can inform decision-making regarding whether and when to continue colorectal cancer screening beyond age 75 among screen-eligible adults.

Genetically predicted circulating concentrations of micronutrients and risk of colorectal cancer among individuals of European descent: a Mendelian randomization study.

BACKGROUND: The literature on associations of circulating concentrations of minerals and vitamins with risk of colorectal cancer is limited and inconsistent. Evidence from randomized controlled trials (RCTs) to support the efficacy of dietary modification or nutrient supplementation for colorectal cancer prevention is also limited. OBJECTIVES: To complement observational and RCT findings, we investigated associations of genetically predicted concentrations of 11 micronutrients (ß-carotene, calcium, copper, folate, iron, magnesium, phosphorus, selenium, vitamin B-6, vitamin B-12, and zinc) with colorectal cancer risk using Mendelian randomization (MR). METHODS: Two-sample MR was conducted using 58,221 individuals with colorectal cancer and 67,694 controls from the Genetics and Epidemiology of Colorectal Cancer Consortium, Colorectal Cancer Transdisciplinary Study, and Colon Cancer Family Registry. Inverse variance-weighted MR analyses were performed with sensitivity analyses to assess the impact of potential violations of MR assumptions. RESULTS: Nominally significant associations were noted for genetically predicted iron concentration and higher risk of colon cancer [ORs per SD (ORSD): 1.08; 95% CI: 1.00, 1.17; P value = 0.05] and similarly for proximal colon cancer, and for vitamin B-12 concentration and higher risk of colorectal cancer (ORSD: 1.12; 95% CI: 1.03, 1.21; P value = 0.01) and similarly for colon cancer. A nominally significant association was also noted for genetically predicted selenium concentration and lower risk of colon cancer (ORSD: 0.98; 95% CI: 0.96, 1.00; P value = 0.05) and similarly for distal colon cancer. These associations were robust to sensitivity analyses. Nominally significant inverse associations were observed for zinc and risk of colorectal and distal colon cancers, but sensitivity analyses could not be performed. None of these findings survived correction for multiple testing. Genetically predicted concentrations of ß-carotene, calcium, copper, folate, magnesium, phosphorus, and vitamin B-6 were not associated with disease risk. CONCLUSIONS: These results suggest possible causal associations of circulating iron and vitamin B-12 (positively) and selenium (inversely) with risk of colon cancer.

A population-based survey to assess the association between cannabis and quality of life among colorectal cancer survivors.

BACKGROUND: As more states legalize cannabis for medical and recreational use, people increasingly use cannabis to treat medical conditions and associated symptoms. The prevalence and utility of cannabis for cancer-related symptoms may be clarified by examining cannabis use among patients with a common cancer diagnosis. We aimed to determine the prevalence of cannabis use among colorectal cancer (CRC) survivors and its associations with quality of life (QoL) and cancer-related symptomatology. METHODS: A cross-sectional survey of patient-reported QoL outcomes and behaviors, including cannabis use, was conducted within the Patient Outcomes To Advance Learning network's (PORTAL) CRC Cohort. The cohort included a population-based sample of healthcare system members ≥18 years old diagnosed with adenocarcinoma of the colon or rectum from 2010 through 2016. We assessed the association between cannabis use and QoL using the European Organization for Research and Treatment of Cancer QLQ-C30 summary score. RESULTS: Of the 1784 respondents, 293 (16.4%) reported cannabis use following CRC diagnosis. Current tobacco smokers were more likely to use cannabis compared to former or never tobacco smokers (adjusted odds ratio [aOR] 2.71, 95% confidence interval [CI] 1.56 to 4.70). Greater alcohol use (> 4 drinks per month versus ≤4 drinks per month) was associated with cannabis use (aOR 2.17, 95% CI 1.65 to 2.85). There was an association between cannabis use and cancer stage at diagnosis, with stage 3 or 4 CRC patients more likely to use cannabis than stage 1 or 2 CRC patients (aOR 1.68, 95% CI 1.25 to 2.25). After adjusting for demographics, medical comorbidities, stage and site of CRC diagnosis, and prescription opioid use, people who used cannabis had significantly lower QoL than people who did not use cannabis (difference of - 6.14, 95% CI - 8.07 to - 4.20). CONCLUSION: Among CRC survivors, cannabis use was relatively common, associated with more advanced stages of disease, associated with tobacco and alcohol use, and not associated with better QoL. Clinicians should inquire about cannabis use among their patients and provide evidence-based recommendations for cancer-related symptoms.

Real-world Clinical Implementation of Lung Cancer Screening-Evaluating Processes to Improve Screening Guidelines-Concordance.

BACKGROUND: Lung cancer screening (LCS) requires complex processes to identify eligible patients, provide appropriate follow-up, and manage findings. It is unclear whether LCS in real-world clinical settings will realize the same benefits as the National Lung Screening Trial (NLST). OBJECTIVE: To evaluate the impact of process modifications on compliance with LCS guidelines during LCS program implementation, and to compare patient characteristics and outcomes with those in NLST. DESIGN: Retrospective cohort study. SETTING: Kaiser Permanente Colorado (KPCO), a non-profit integrated healthcare system. PATIENTS: A total of 3375 patients who underwent a baseline lung cancer screening low-dose computed tomography (S-LDCT) scan between May 2014 and June 2017. MEASUREMENTS: Among those receiving an S-LDCT, proportion who met guidelines-based LCS eligibility criteria before and after LCS process modifications, differences in patient characteristics and outcomes between KPCO LCS patients and the NLST cohort, and factors associated with a positive screen. RESULTS: After modifying LCS eligibility confirmation processes, patients receiving S-LDCT who met guidelines-based LCS eligibility criteria increased from 45.6 to 92.7% (P < 0.001). Prior to changes, patients were older (68 vs. 67 years; P = 0.001), less likely to be current smokers (51.3% vs. 52.5%; P < 0.001), and less likely to have a ≥ 30-pack-year smoking history (50.0% vs. 95.3%; P < 0.001). Compared with NLST participants, KPCO LCS patients were older (67 vs. 60 years; P < 0.001), more likely to currently smoke (52.3% vs. 48.1%; P < 0.001), and more likely to have pulmonary disease. Among those with a positive baseline S-LDCT, the lung cancer detection rate was higher at KPCO (9.4% vs. 3.8%; P < 0.001) and was positively associated with prior pulmonary disease. CONCLUSION: Adherence to LCS guidelines requires eligibility confirmation procedures. Among those with a positive baseline S-LDCT, comorbidity burden and lung cancer detection rates were notably higher than in NLST, suggesting that the study of long-term outcomes in patients undergoing LCS in real-world clinical settings is warranted.

Predictors of Long-Term Survival among High-Grade Serous Ovarian Cancer Patients.

BACKGROUND: Relatively little is known about factors associated with long-term survival (LTS) following a diagnosis of ovarian cancer. METHODS: We conducted a retrospective study of high-grade serous ovarian cancer (HGSOC) to explore predictors of LTS (defined as ≥7 years of survival) using electronic medical record data from a network of integrated health care systems. Multivariable logistic regression with forward selection was used to compare characteristics of women who survived ≥7 years after diagnosis (n = 148) to those who died within 7 years of diagnosis (n = 494). RESULTS: Our final model included study site, age, stage at diagnosis, CA-125, comorbidity score, receipt of chemotherapy, BMI, and four separate comorbid conditions: weight loss, depression, hypothyroidism, and liver disease. Of these, only younger age, lower stage, and depression were statistically significantly associated with LTS. CONCLUSIONS: We did not identify any new characteristics associated with HGSOC survival. IMPACT: Prognosis of ovarian cancer generally remains poor. Large, pooled studies of ovarian cancer are needed to identify characteristics that may improve survival.

Risk of colon cancer recurrence in relation to diabetes.

PURPOSE: To describe the association between diabetes and colon cancer recurrence. METHODS: We conducted a cohort study at two integrated health care delivery systems in the United States. Using tumor registry data, we identified patients aged ≥ 18 years when diagnosed with stage I-IIIA adenocarcinomas of the colon during 1995-2014. Pre-existing diabetes was ascertained via diagnosis codes. Medical records were reviewed for eligibility and to abstract recurrence and covariate information. Recurrence was ascertained beginning 90 days after the end of colon cancer treatment (i.e., cohort entry). Recurrence of any cancer or a new primary cancer at any site was a secondary outcome. We used multivariable Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (CIs) for the associations between diabetes at cohort entry and study outcomes. RESULTS: Among the 1,923 eligible patients, 393 (16.7%) had diabetes at cohort entry. Diabetes was not associated with recurrence (HR 0.87; 95% CI 0.56-1.33) or with any subsequent cancer (HR 1.09; 95% CI 0.85-1.40). When the definition of recurrence included second primary colorectal cancer, risk was non-significantly higher in patients with diabetes than without diabetes. CONCLUSIONS: The risk of colon cancer recurrence appears to be similar in patients with and without diabetes at diagnosis. IMPACT: Future studies should evaluate the association between diabetes and colorectal cancer outcomes, especially second primary colon cancers, in larger populations.

Telomere length differences between colorectal polyp subtypes: a colonoscopy-based case-control study.

BACKGROUND: Short telomeres have been associated with increased risk of many cancers, particularly cancers of the gastrointestinal tract including esophagus and stomach. However, the association between telomere length (TL) and colorectal cancer and its precursors, colorectal polyps, is not clear. METHODS: We investigated the relationship between TL and risk of colorectal polyp subtypes in a colonoscopy-based study in western Washington. Participants were 35-79 year-old enrollees at an integrated health care system, who underwent a colonoscopy between 1998 and 2007 (n = 190), completed a self-administered questionnaire, provided blood samples, and were distinguished as having adenomas, serrated polyps, or as polyp-free controls through a standardized pathology review. Telomere length (T) relative to a single copy gene (S) was measured in circulating leukocytes from stored buffy coat samples using quantitative polymerase chain reaction. Multivariable polytomous logistic regression was used to compare case groups with polyp-free controls and other case groups; adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated. RESULTS: TL in the shortest tertile (T/S ratio < 0.58) was associated with increased risk of adenomas and serrated polyps [OR (95%CI) were 1.77(0.81-3.88) and 2.98(1.15-7.77), respectively). When evaluated by lesion severity within each pathway, short TL was more strongly associated with advanced adenomas and sessile serrated polyps [OR (95% CI) = 1.90(0.76-4.73) and 3.82(0.86-16.86), respectively], although the associations were not statistically significant. CONCLUSIONS: Our results suggest that short TL may be associated with an increased risk of colorectal polyps in both the adenoma-carcinoma and serrated pathways. The risk was particularly notable for sessile serrated polyps, although the association was not statistically significant and sample size was limited.

Reproductive factors and risk of colorectal polyps in a colonoscopy-based study in western Washington State.

BACKGROUND: Oral contraceptives (OC) are associated with a decreased risk of colorectal cancers; however, a recent study reported an increased risk of small colorectal adenomas associated with OC use. To determine if these results were replicable in a different study population, we investigated the relationship between OC use and other reproductive factors and risk of colorectal polyps in a case-control study in western Washington. METHODS: Study participants were 24-79-year-old female enrollees at an integrated health care system in western Washington who were diagnosed as having adenomas (n = 299), serrated polyps (n = 337), both types of polyps (n = 105) or as polyp-free controls (n = 615) through an index colonoscopy and completed a structured interview to collect reproductive history information. Multivariable polytomous logistic regression was used to compare case groups to controls and to each other; odds ratios (OR) and 95% confidence intervals were estimated. RESULTS: There was no association between OC use, duration of use, or recency of use and the risk of either adenomas or serrated polyps [adjusted OR for OC ever use (95% CI) 0.85 (0.58-1.23) and 0.96 (0.66-1.40), respectively], and associations did not differ by lesion severity within the adenoma or serrated pathways. Further, no associations were observed between other reproductive factors and risk of colorectal polyp subtypes. CONCLUSIONS: Our results suggest that reproductive factors, including OC use, are not associated with early colorectal cancer precursor lesions.

No association between germline variation in catechol-O-methyltransferase and colorectal cancer survival in postmenopausal women.

OBJECTIVE: Sex steroid hormones play a role in colorectal cancer (CRC) development, but little is known about their influence on tumor progression and metastasis. Because catechol-O-methyltransferase (COMT; 22q11.21) activity is an important component of estrogen-mediated carcinogenesis, we hypothesized that germline variation in COMT may be associated with CRC survival. METHODS: We identified 10 single nucleotide polymorphisms that tagged variation across two isoforms of COMT in 2,458 women with CRC from the Nurses' Health Study, Postmenopausal Hormones Supplementary Study to the Colon Cancer Family Registry, VITamins And Lifestyle Study, and Women's Health Initiative. All four studies participated in the Genetics and Epidemiology of Colorectal Cancer Consortium. RESULTS: During a median follow-up of 7 years across all studies, there were 799 deaths, including 566 deaths from CRC. Based on multiple comparisons, no associations between single nucleotide polymorphisms and CRC-specific or overall survival reached statistical significance, including the well-characterized Val108/158Met polymorphism (rs4680; CRC-specific survival: hazard ratio per minor allele, 1.04; 95% CI, 0.92-1.17; overall survival: hazard ratio per minor allele, 1.01; 95% CI, 0.90-1.14). CONCLUSIONS: In this large study of women with CRC, we find no evidence that common inherited variation in COMT is associated with survival time after diagnosis.

Circulating 25-hydroxyvitamin-D and risk of colorectal adenomas and hyperplastic polyps.

Colorectal adenomas are clear precursors of cancer; hyperplastic polyps may also have malignant potential. An inverse association between circulating vitamin D metabolites and adenoma risk has been reported, but less is known about vitamin D and hyperplastic polyps. We conducted a case-control study of adenomas and hyperplastic polyps among 459 members of an integrated health plan evaluated via colonoscopy. Questionnaires provided information on colorectal polyp risk factors, and plasma samples were assayed for 25-hydroxyvitamin-D [25(OH)D]. Polytomous regression was used to estimate odds ratios for adenomas (n = 149) and hyperplastic polyps (n = 85) compared to polyp-free controls (n = 225) by tertile of 25(OH)D. An inverse association between 25(OH)D and adenomas was suggested after adjustment for potential confounding factors [comparing upper to lower tertiles, OR (95%CI): 0.71 (0.38-1.30)]. After restriction of the analyses to study participants with no history of polyps, this OR estimate was reduced further [adjusted OR (95%CI): 0.52 (0.23-1.20)]. In comparison, no inverse association between hyperplastic polyps and 25(OH)D was observed among the full study participants [adjusted OR (95%CI): 1.17 (0.55-2.51)] or among those without prior polyps [adjusted OR (95%CI): 1.42 (0.55-3.65)]. Our study suggests that the established inverse association between circulating 25(OH)D and adenoma may not apply to hyperplastic polyps.

Body size, IGF and growth hormone polymorphisms, and colorectal adenomas and hyperplastic polyps.

OBJECTIVE: We examined the risk of colorectal polyps in relation to body size factors and candidate polymorphisms in selected genes of insulin-like growth factor (IGF1) (rs5742612), IGF1 receptor (IGF1R) (rs2229765), IGF binding protein 3 (IGFBP3) (rs2854746) and growth hormone (GH1) (rs2665802). DESIGN: Cases with colorectal adenomas (n=519), hyperplastic polyps (n=691), or both lesions (n=227), and controls (n=772), aged 20-74 years, were recruited from patients who underwent colonoscopy between December 2004 and September 2007 at a large integrated-health plan in Washington state. Subjects participated in a 45-minute telephone interview to ascertain body size and physical activity, and provided a buccal DNA sample for genetic analysis. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using multivariable polytomous regression. RESULTS: Compared to those of normal weight, higher body mass index (BMI) was associated with elevated risk of colorectal adenomas (OR=1.65, 95% CI 1.22-2.25 BMI>or=30 kg/m(2), p-trend=0.002) and both lesions (OR=2.15, 95% CI 1.43-3.22 BMI>or=30 kg/m(2), p-trend=0.003), but there was no relationship with hyperplastic polyps. Obesity at age 18 and a weight gain of >or=21 kg since age 18 were also significantly associated with an increased risk of colorectal adenomas and both lesions, but not hyperplastic polyps. There was a reduced risk of colorectal adenomas (OR=0.63, 95% CI 0.42-0.94) and hyperplastic polyps (OR=0.7, 95% CI 0.5-0.9) associated with the homozygous variant genotype for GH1. Few meaningful results were evident for the other polymorphisms. CONCLUSIONS: There is an increased risk of colorectal adenomas and presence of both adenomas and hyperplastic polyps in relation to increasing body size. Some genetic variation in GH1 might contribute to a reduced risk of colorectal adenomas and hyperplastic polyps.

Multivitamin supplement use and risk of invasive breast cancer.

OBJECTIVE: Multivitamin supplements are used by nearly half of middle-aged women in the USA. Despite this high prevalence of multivitamin use, little is known about the effects of multivitamins on health outcomes, including cancer risk. Our main objective was to determine the association between multivitamin use and the risk of breast cancer in women. DESIGN: We conducted a population-based case-control study among 2968 incident breast cancer cases (aged 20-69 years), diagnosed between 2004 and 2007, and 2982 control women from Wisconsin, USA. All participants completed a structured telephone interview which ascertained supplement use prior to diagnosis, demographics and risk factor information. Odds ratios and 95 % confidence intervals were calculated using multivariable logistic regression. RESULTS: Compared with never users of multivitamins, the OR for breast cancer was 1.02 (95 % CI 0.87, 1.19) for current users and 0.99 (95 % CI 0.74, 1.33) for former users. Further, neither duration of use (for > or =10 years: OR = 1.13, 95 % CI 0.93, 1.38, P for trend = 0.25) nor frequency (>7 times/week: OR = 1.00, 95 % CI 0.77, 1.28, P for trend = 0.97) was related to risk in current users. Stratification by menopausal status, family history of breast cancer, age, alcohol, tumour staging and postmenopausal hormone use did not significantly modify the association between multivitamin use and breast cancer. CONCLUSIONS: The current study found no association between multivitamin supplement use and breast cancer risk in women.

Supplement use contributes to meeting recommended dietary intakes for calcium, magnesium, and vitamin C in four ethnicities of middle-aged and older Americans: the Multi-Ethnic Study of Atherosclerosis.

BACKGROUND: Low intake of nutrients is associated with poor health outcomes. We examined the contribution of dietary supplementation to meeting recommended dietary intakes of calcium, magnesium, potassium, and vitamin C in participants of the Multi-Ethnic Study of Atherosclerosis, a cohort of white, African-American, Hispanic, and Chinese-American participants ages 45 to 84 years. We also assessed the prevalence of intakes above Tolerable Upper Intake Levels (ULs). METHODS: At the baseline exam in 2000-2001, 2,938 men and 3,299 women completed food frequency questionnaires and provided information about dietary supplementation. We used relative risk regression to estimate the probability of meeting Recommended Dietary Allowances (RDAs) or Adequate Intakes (AIs) in supplement users vs nonusers and Fisher's exact tests to compare the proportion of those exceeding ULs between the two groups. RDAs, AIs, and ULs were defined by the National Academy of Sciences Food and Nutrition Board's Dietary Reference Intakes (DRIs). RESULTS: After adjustment for age and education, the relative risk of meeting RDAs or AIs in supplement-users vs nonusers ranged from 1.9 (1.6, 2.3) in white men to 5.7 (4.1, 8.0) in African-American women for calcium, from 2.5 (1.9, 3.3) in Hispanic men to 5.2 (2.4, 11.2) in Chinese men for magnesium, and from 1.4 (1.3, 1.5) in African-American women to 2.0 (1.7, 2.2) in Chinese men for vitamin C. The relative risks for meeting RDAs for calcium differed significantly by ethnicity (P<0.001) and sex (P<0.001), and by ethnicity for magnesium (P=0.01). The relative risk for each sex/ethnicity strata was close to 1 and did not reach statistical significance at alpha=.05 for potassium. For calcium, 15% of high-dose supplement users exceeded the UL compared with only 2.1% of nonusers. For vitamin C, the percentages were 6.6% and 0%, and for magnesium, 35.3% and 0% (P<0.001 for all). CONCLUSIONS: Although supplement use is associated with meeting DRI guidelines for calcium, vitamin C and magnesium, many adults are not meeting the DRI guidelines even with the help of dietary supplements, and the effect of supplementation can vary according to ethnicity and sex. However, supplementation was not significantly associated with meeting DRIs for potassium. Also, high-dose supplement use is associated with intakes above ULs for calcium, magnesium, and vitamin C.