Evaluation of a Novel Ambient Light Survey Question in the Cancer Prevention Study-3

Nighttime light exposure may increase cancer risk by disrupting the circadian system. However, there is no well-established survey method for measuring ambient light. In the Cancer Prevention Study-3, 732 men and women answered a light survey based on seven environments. The light environment in the past year was assessed twice, one year apart, and four one-week diaries were collected between the annual surveys. A total of 170 participants wore a meter to measure photopic illuminance and circadian stimulus (CS). Illuminance and CS values were estimated for lighting environments from measured values and evaluated with a cross validation approach. The kappas for self-reported light environment comparing the two annual surveys were 0.61 on workdays and 0.49 on non-workdays. Kappas comparing the annual survey to weekly diaries were 0.71 and 0.57 for work and non-workdays, respectively. Agreement was highest for reporting of darkness (95.3%), non-residential light (86.5%), and household light (75.6%) on workdays. Measured illuminance and CS identified three peaks of light (darkness, indoor lighting, and outdoor daytime light). Estimated illuminance and CS were correlated with the measured values overall (r = 0.77 and r = 0.67, respectively) but were less correlated within each light environment (r = 0.23-0.43). The survey has good validity to assess ambient light for studies of human health.

Clonal hematopoiesis and risk of prostate cancer in large samples of European ancestry men

Little is known regarding the potential relationship between clonal hematopoiesis (CH) of indeterminate potential (CHIP), which is the expansion of hematopoietic stem cells with somatic mutations, and risk of prostate cancer, the fifth leading cause of cancer death of men worldwide. We evaluated the association of age-related CHIP with overall and aggressive prostate cancer risk in two large whole-exome sequencing studies of 75 047 European ancestry men, including 7663 prostate cancer cases, 2770 of which had aggressive disease, and 3266 men carrying CHIP variants. We found that CHIP, defined by over 50 CHIP genes individually and in aggregate, was not significantly associated with overall (aggregate HR = 0.93, 95% CI = 0.76-1.13, P = 0.46) or aggressive (aggregate OR = 1.14, 95% CI = 0.92-1.41, P = 0.22) prostate cancer risk. CHIP was weakly associated with genetic risk of overall prostate cancer, measured using a polygenic risk score (OR = 1.05 per unit increase, 95% CI = 1.01-1.10, P = 0.01). CHIP was not significantly associated with carrying pathogenic/likely pathogenic/deleterious variants in DNA repair genes, which have previously been found to be associated with aggressive prostate cancer. While findings from this study suggest that CHIP is likely not a risk factor for prostate cancer, it will be important to investigate other types of CH in association with prostate cancer risk.

Grain, gluten, and dietary fiber intake influence gut microbial diversity: data from the Food and Microbiome Longitudinal Investigation (FAMiLI)

Although short-term feeding studies demonstrated effects of grains, fiber, and gluten on gut microbiome composition, the impact of habitual intake of these dietary factors is poorly understood. We examined whether habitual intakes of whole and refined grains, fiber, and gluten are associated with gut microbiota in a cross-sectional study. This study included 779 participants from the multi-ethnic FAMiLI study. Bacterial 16SV4 rRNA gene from baseline stool was amplified and sequenced using Illumina MiSeq. Read clustering and taxonomic assignment was performed using Qiime2. Usual dietary intake was assessed by a 137-item food frequency questionnaire. Association of diet with gut microbiota was assessed with respect to overall composition and specific taxon abundances. Whole grain intake was associated with overall composition, as measured by the Jensen-Shannon divergence (multivariable-adjusted P-trend for quartiles=0.03). The highest intake quartile was associated with higher abundance of Bacteroides plebeius, Faecalibacterium prausnitzii, Blautia producta, and Erysipelotrichaceae and lower abundance of Bacteroides uniformis. These bacteria also varied by dietary fiber intake. Higher refined grain and gluten intake was associated with lower Shannon diversity (P-trend<0.05). These findings suggest that whole grain and dietary fiber are associated with overall gut microbiome structure, largely fiber-fermenting microbiota. Higher refined grain and gluten intakes may be associated with lower microbial diversity.

Coffee consumption and risk of endometrial cancer: a pooled analysis of individual participant data in the Epidemiology of Endometrial Cancer Consortium (E2C2)

BACKGROUND

Epidemiologic studies suggest that coffee consumption may be inversely associated with risk of endometrial cancer (EC), the most common gynecological malignancy in developed countries. Furthermore, coffee consumption may lower circulating concentrations of estrogen and insulin, hormones implicated in endometrial carcinogenesis. Antioxidants and other chemopreventive compounds in coffee may have anticarcinogenic effects. Based on available meta-analyses, the World Cancer Research Fund (WCRF) concluded that consumption of coffee probably protects against EC.

OBJECTIVES

Our main aim was to examine the association between coffee consumption and EC risk by combining individual-level data in a pooled analysis. We also sought to evaluate potential effect modification by other risk factors for EC.

METHODS

We combined individual-level data from 19 epidemiologic studies (6 cohort, 13 case-control) of 12,159 EC cases and 27,479 controls from the Epidemiology of Endometrial Cancer Consortium (E2C2). Logistic regression was used to calculate ORs and their corresponding 95% CIs. All models were adjusted for potential confounders including age, race, BMI, smoking status, diabetes status, study design, and study site.

RESULTS

Coffee drinkers had a lower risk of EC than non-coffee drinkers (multiadjusted OR: 0.87; 95% CI: 0.79, 0.95). There was a dose-response relation between higher coffee consumption and lower risk of EC: compared with non-coffee drinkers, the adjusted pooled ORs for those who drank 1, 2-3, and >4 cups/d were 0.90 (95% CI: 0.82, 1.00), 0.86 (95% CI: 0.78, 0.95), and 0.76 (95% CI: 0.66, 0.87), respectively (P-trend < 0.001). The inverse association between coffee consumption and EC risk was stronger in participants with BMI > 25 kg/m2.

CONCLUSIONS

The results of the largest analysis to date pooling individual-level data further support the potentially beneficial health effects of coffee consumption in relation to EC, especially among females with higher BMI.

Prospective associations of hemoglobin A1c and c-peptide with risk of diabetes-related cancers in the Cancer Prevention Study-II Nutrition Cohort

Self-reported type 2 diabetes mellitus (T2DM) is a risk factor for many cancers, suggesting its pathology relates to carcinogenesis. We conducted a case-cohort study to examine associations of hemoglobin A1c (HbA1c) and c-peptide with cancers associated with self-reported T2DM. This study was drawn from a prospective cohort of 32,383 women and men who provided blood specimens at baseline: c-peptide and HbA1c were assessed in 3,000 randomly selected participants who were cancer-free-at-baseline and an additional 2,281 participants who were cancer-free-at-baseline and subsequently diagnosed with incident colorectal, liver, pancreatic, female breast, endometrial, ovarian, bladder, or kidney cancers. Weighted-Cox regression models estimated hazards ratios (HRs) and 95% confidence intervals (CI), adjusted for covariates. C-peptide was associated with higher risk of liver cancer (per standard deviation (SD) HR: 1.80; 95%CI: 1.32-2.46). HbA1c was associated with higher risk of pancreatic cancer (per SD HR: 1.21 95%CI 1.05-1.40) and with some suggestion of higher risks for all-cancers-of-interest (per SD HR: 1.05; 95%CI: 0.99-1.11) and colorectal (per SD HR: 1.09; 95%CI: 0.98-1.20), ovarian (per SD HR: 1.18; 95%CI 0.96-1.45) and bladder (per SD HR: 1.08; 95%CI 0.96-1.21) cancers. Compared to no self-reported T2DM and HbA1c <6.5% (reference group), self-reported T2DM and HbA1c <6.5% (i.e., T2DM in good glycemic control) was not associated with risk of colorectal cancer, whereas it was associated with higher risks of all-cancers-of-interest combined (HR: 1.28; 95%CI: 1.01-1.62), especially for breast and endometrial cancers. Additional large, prospective studies are needed to further explore the roles of hyperglycemia, hyperinsulinemia, and related metabolic traits with T2DM-associated cancers to better understand the mechanisms underlying the self-reported T2DM-cancer association and to identify persons at higher cancer risk.

Abstract 688: Multi-stage exome sequencing study of 17,546 aggressive and non-aggressive prostate cancer cases

Rare pathogenic variants in DNA repair genes have been found to influence risk of aggressive prostate cancer. We conducted a large case-only exome sequencing study to further understand the role of rare coding variation in aggressive prostate cancer in a study of 9,185 aggressive (prostate cancer death, metastatic disease, T4, or both T3 and Gleason≥8) and 8,361 non-aggressive cases (T1/T2 and Gleason≤6) of European ancestry from 19 international studies. Stage 1 samples (N=5,545) had whole exome-sequencing, and stage 2 samples (N=12,001) had targeted exome sequencing for 1,459 genes selected based on stage 1 results and previous evidence. Logistic regression models were used to evaluate gene-based tests and the aggregate effect of multiple genes to investigate whether carrying pathogenic/likely pathogenic/deleterious (P/LP/D) variants (18,759 identified) was associated with risk of aggressive prostate cancer, prostate cancer death (N=6,033), or metastatic disease (N=1,730) compared to non-aggressive disease. Gene-based tests were meta-analyzed across stages 1 and 2. BRCA2, ATM, and NBN had the most statistically significant gene-based results: BRCA2 P/LP/D variant carriers had 4.3-fold higher odds of aggressive disease (95% CI=3.15-5.86, P=4x10-20), 4.7-fold higher odds of prostate cancer death (95% CI=3.41-6.59, P=2x10-20), and 5.7-fold higher odds of metastatic disease (95% CI=3.71-8.76, P=2x10-15); ATM P/LP/D variant carriers had 2.2-fold higher odds of aggressive disease (95% CI=1.58-2.99, P=2x10-6), 2.2-fold higher odds of prostate cancer death (95% CI=1.52-3.05, P=2x10-5), and 3.0-fold higher odds of metastatic disease (95% CI=1.93-4.61, P=9x10-7); and NBN P/LP/D variant carriers had 5.9-fold higher odds of metastatic disease (95% CI=2.56-13.84, P=3x10-5). Among potentially novel genes with strong but not exome-wide significant statistical evidence were MMP19, involved in reproduction and metastasis, with carriers having 2.8-fold higher odds of prostate cancer death (95% CI=1.53-5.05, P=8x10-4); PKD2L2, involved in fertility, with carriers having 3.5-fold higher odds of prostate cancer death (95% CI=1.76-7.04, P=5x10-4); and SMPD1, involved in converting sphingomyelin to ceramide, with carriers having 5.3-fold higher odds of metastatic disease (95% CI=1.85-14.98, P=0.002). At least one P/LP/D variant within a subset of 24 previously curated candidate prostate cancer DNA repair genes was carried by 12.8% of aggressive cases (OR=1.48, 95% CI=1.34-1.64, P=3x10-14), 12.6% of cases who died due to prostate cancer (OR=1.47, 95% CI=1.31-1.65, P=3x10-11), and 15.1% of metastatic cases (OR=2.16, 95% CI=1.57-2.16, P=5x10-14) compared to 9.4% of non-aggressive cases. These findings support the importance of rare genetic variation in aggressive prostate cancer risk and may have important implications for prostate cancer risk stratification and screening.

Citation Format: Burcu F. Darst, Ed Saunders, Tokhir Dadaev, Xin Sheng, Peggy Wan, Loreall Pooler, Lucy Y. Xia, Stephen Chanock, Sonja I. Berndt, Susan M. Gapstur, Victoria Stevens, Demetrius Albanes, Stephanie J. Weinstein, Vincent Gnanapragasam, Graham G. Giles, Tu Nguyen-Dumont, Roger L. Milne, Mark M. Pomerantz, Julie A. Schmidt, Ruth C. Travis, Timothy J. Key, Konrad H. Stopsack, Lorelei A. Mucci, William J. Catalona, Beth Marosy, Kurt N. Hetrick, Kimberly F. Doheny, Robert J. MacInnis, Melissa C. Southey, Rosalind A. Eeles, Fredrik Wiklund, Zsofia Kote-Jarai, David V. Conti, Christopher A. Haiman. Multi-stage exome sequencing study of 17,546 aggressive and non-aggressive prostate cancer cases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 688.

Age-related health deficits and five-year mortality among older, long-term cancer survivors

INTRODUCTION

Geriatric assessment evaluates multiple domains of health that, together, are superior to using chronologic age for predicting outcomes, such as hospitalization and mortality among patients with cancer. Most studies have not included comparison groups of individuals without cancer and assessed domains around the time of initial cancer diagnosis. Further, the potential for brief, self-reported measures to capture deficits that similarly predict mortality has not been well examined. This study compared age-related health deficit prevalence between older, long-term cancer survivors and individuals without a cancer history, and estimated associations between deficits and mortality risk among survivors.

MATERIALS AND METHODS

Analyses included participants in the Cancer Prevention Study (CPS)-II Nutrition Cohort who were cancer-free at enrollment in 1992/1993 and completed the Patient Reported Outcome Measurement Information System® (PROMIS®) global health questionnaire in 2011. Age-related deficits in five domains (comorbidities, functional status, mental health, malnutrition/weight loss, and social support) were self-reported. Cancer information was self-reported and confirmed via medical records or state cancer registries. Vital status through 2016 and cause of death was ascertained by linkage with the National Death Index.

RESULTS

Analyses included 9979 participants (median age = 80) diagnosed with invasive cancer 5-20 years prior to completing the 2011 survey and 63,578 participants without a cancer history (median age = 79). Overall deficits in the five domains were similar among long-term cancer survivors and controls. However, survivors of specific cancer types - non-Hodgkin lymphoma (NHL), lung, and kidney cancer - were more likely to report deficits in mental health and functional status than the control group. Among all survivors, each domain was independently associated with all-cause mortality, particularly functional status (hazard ratio [HR] = 2.02; 95% confidence interval [CI]: 1.80-2.27) and mental health (HR = 1.84; 95% CI: 1.65-2.04). Mortality risk increased with the number of deficits.

DISCUSSION

These results suggest that, several years after treatment, NHL, lung, and kidney cancer survivors are still more likely to experience age-related deficits compared to other similarly-aged individuals. Furthermore, results show that shorter, self-reported physical and mental health assessments, such as the PROMIS® global health questions, are predictive of mortality among older, long-term cancer survivors and, therefore, may be useful in clinical and research settings.

American Cancer Society nutrition and physical activity guideline for cancer survivors

The overall 5-year relative survival rate for all cancers combined is now 68%, and there are over 16.9 million survivors in the United States. Evidence from laboratory and observational studies suggests that factors such as diet, physical activity, and obesity may affect risk for recurrence and overall survival after a cancer diagnosis. The purpose of this American Cancer Society guideline is to provide evidence-based, cancer-specific recommendations for anthropometric parameters, physical activity, diet, and alcohol intake for reducing recurrence and cancer-specific and overall mortality. The audiences for this guideline are health care providers caring for cancer survivors as well as cancer survivors and their families. The guideline is intended to serve as a resource for informing American Cancer Society programs, health policy, and the media. Sources of evidence that form the basis of this guideline are systematic literature reviews, meta-analyses, pooled analyses of cohort studies, and large randomized clinical trials published since 2012. Recommendations for nutrition and physical activity during cancer treatment, informed by current practice, large cancer care organizations, and reviews of other expert bodies, are also presented. To provide additional context for the guidelines, the authors also include information on the relationship between health-related behaviors and comorbidities, long-term sequelae and patient-reported outcomes, and health disparities, with attention to enabling survivors' ability to adhere to recommendations. Approaches to meet survivors' needs are addressed as well as clinical care coordination and resources for nutrition and physical activity counseling after a cancer diagnosis.

Biomarkers of glucose homeostasis and inflammation with risk of prostate cancer: A case-cohort study

BACKGROUND

Few prospective studies have examined biomarkers of glucose homeostasis or inflammation with prostate cancer risk by tumor stage or grade.

METHODS

We conducted a case-cohort study to examine associations of pre-diagnosis hemoglobin A1c (HbA1c), c-peptide, and c-reactive protein (CRP) with prostate cancer risk overall and stratified by tumor stage and grade. The study included 390 non-aggressive (T1-2, N0, M0 and Gleason score <8) and 313 aggressive cases (T3-4, or N1, or M1, or Gleason score 8-10) diagnosed after blood draw (1998-2001) and up to 2013, and a random sub-cohort of 1,303 cancer-free men at blood draw in the Cancer Prevention Study-II Nutrition Cohort. Prentice-weighted Cox proportional hazards regression models were used to estimate hazards ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

In the multivariable-adjusted model without body mass index (BMI), HbA1c was inversely associated with non-aggressive prostate cancer (HR per unit increase: 0.89, 95% CI: 0.80-1.00, P=0.04). Analyses stratified by tumor stage and grade separately showed that HbA1c was inversely associated with low-grade prostate cancer (HR per unit increase: 0.89, 95% CI: 0.80-1.00) and positively associated with high-grade prostate cancer (HR per unit increase: 1.15, 95% CI: 1.01-1.30). C-peptide and CRP were not associated with prostate cancer overall or by stage or grade.

CONCLUSIONS

The present study suggests that associations of hyperglycemia with prostate cancer may differ by tumor grade and stage.

IMPACT

Future studies need to examine prostate cancer by tumor stage and grade, and to better understand the role of hyperglycemia in prostate cancer progression.

A Rare Germline HOXB13 Variant Contributes to Risk of Prostate Cancer in Men of African Ancestry

A rare African ancestry-specific germline deletion variant in HOXB13 (X285K, rs77179853) was recently reported in Martinican men with early-onset prostate cancer. Given the role of HOXB13 germline variation in prostate cancer, we investigated the association between HOXB13 X285K and prostate cancer risk in a large sample of 22 361 African ancestry men, including 11 688 prostate cancer cases. The risk allele was present only in men of West African ancestry, with an allele frequency in men that ranged from 0.40% in Ghana and 0.31% in Nigeria to 0% in Uganda and South Africa, with a range of frequencies in men with admixed African ancestry from North America and Europe (0-0.26%). HOXB13 X285K was associated with 2.4-fold increased odds of prostate cancer (95% confidence interval [CI] = 1.5-3.9, p = 2 × 10^-4), with greater risk observed for more aggressive and advanced disease (Gleason ≥8: odds ratio [OR] = 4.7, 95% CI = 2.3-9.5, p = 2 × 10^-5; stage T3/T4: OR = 4.5, 95% CI = 2.0-10.0, p = 2 × 10^-4; metastatic disease: OR = 5.1, 95% CI = 1.9-13.7, p = 0.001). We estimated that the allele arose in West Africa 1500-4600 yr ago. Further analysis is needed to understand how the HOXB13 X285K variant impacts the HOXB13 protein and function in the prostate. Understanding who carries this mutation may inform prostate cancer screening in men of West African ancestry. PATIENT SUMMARY: A rare African ancestry-specific germline deletion in HOXB13, found only in men of West African ancestry, was reported to be associated with an increased risk of overall and advanced prostate cancer. Understanding who carries this mutation may help inform screening for prostate cancer in men of West African ancestry.

Common variants in breast cancer risk loci predispose to distinct tumor subtypes

BACKGROUND

Genome-wide association studies (GWAS) have identified multiple common breast cancer susceptibility variants. Many of these variants have differential associations by estrogen receptor (ER) status, but how these variants relate with other tumor features and intrinsic molecular subtypes is unclear.

METHODS

Among 106,571 invasive breast cancer cases and 95,762 controls of European ancestry with data on 173 breast cancer variants identified in previous GWAS, we used novel two-stage polytomous logistic regression models to evaluate variants in relation to multiple tumor features (ER, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and grade) adjusting for each other, and to intrinsic-like subtypes.

RESULTS

Eighty-five of 173 variants were associated with at least one tumor feature (false discovery rate < 5%), most commonly ER and grade, followed by PR and HER2. Models for intrinsic-like subtypes found nearly all of these variants (83 of 85) associated at p < 0.05 with risk for at least one luminal-like subtype, and approximately half (41 of 85) of the variants were associated with risk of at least one non-luminal subtype, including 32 variants associated with triple-negative (TN) disease. Ten variants were associated with risk of all subtypes in different magnitude. Five variants were associated with risk of luminal A-like and TN subtypes in opposite directions.

CONCLUSION

This report demonstrates a high level of complexity in the etiology heterogeneity of breast cancer susceptibility variants and can inform investigations of subtype-specific risk prediction.

Alcohol and Cancer: Existing Knowledge and Evidence Gaps across the Cancer Continuum

Alcoholic beverages are carcinogenic to humans. Globally, an estimated 4.1% of new cancer cases in 2020 were attributable to alcoholic beverages. However, the full cancer burden due to alcohol is uncertain because for many cancer (sub)types, associations remain inconclusive. Additionally, associations of consumption with therapeutic response, disease progression, and long-term cancer outcomes are not fully understood, public awareness of the alcohol-cancer link is low, and the interrelationships of alcohol control regulations and cancer risk are unclear. In December 2020, the U.S. NCI convened a workshop and public webinar that brought together a panel of scientific experts to review what is known about and identify knowledge gaps regarding alcohol and cancer. Examples of gaps identified include: (i) associations of alcohol consumption patterns across the life course with cancer risk; (ii) alcohol's systemic carcinogenic effects; (iii) alcohol's influence on treatment efficacy, patient-reported outcomes, and long-term prognosis; (iv) communication strategies to increase awareness of the alcohol-cancer link; and (v) the impact of alcohol control policies to reduce consumption on cancer incidence and mortality. Interdisciplinary research and implementation efforts are needed to increase relevant knowledge, and to develop effective interventions focused on improving awareness, and reducing harmful consumption to decrease the alcohol-related cancer burden.

Applying the Strategic Planning Process to a Large Research Consortium: The Example of the National Cancer Institute Cohort Consortium

Strategic planning is conducted by many organizations to systematically evaluate and assess their current state, establish or update their mission and/or goals, and identify strategies and activities to achieve the goals. The National Cancer Institute (NCI) Cohort Consortium is a collaborative network of 62 prospective cohort studies and their affiliated investigators that focus on cancer etiology and outcome research. The organization's membership grew markedly from 10 cohort studies at its inception in 2001 to 59 cohort studies at the time of the launch of the Consortium's strategic planning in 2017. This paper describes the strategic planning process that was conducted to establish organizational goals and to develop strategies and activities consistent with the Consortium's mission. The process involved a 2-year iterative approach combining surveys and in-person meetings. The resulting goals focus on communication, career development, research facilitation, scientific gaps, and common scientific challenges. The NCI Cohort Consortium's strategic plan and evaluation of its progress will advance new initiatives in cancer etiology and survivorship research.

Genome-wide homozygosity and risk of four non-Hodgkin lymphoma subtypes

AIM

Recessive genetic variation is thought to play a role in non-Hodgkin lymphoma (NHL) etiology. Runs of homozygosity (ROH), defined based on long, continuous segments of homozygous SNPs, can be used to estimate both measured and unmeasured recessive genetic variation. We sought to examine genome-wide homozygosity and NHL risk.

METHODS

We used data from eight genome-wide association studies of four common NHL subtypes: 3061 chronic lymphocytic leukemia (CLL), 3814 diffuse large B-cell lymphoma (DLBCL), 2784 follicular lymphoma (FL), and 808 marginal zone lymphoma (MZL) cases, as well as 9374 controls. We examined the effect of homozygous variation on risk by: (1) estimating the fraction of the autosome containing runs of homozygosity (FROH); (2) calculating an inbreeding coefficient derived from the correlation among uniting gametes (F3); and (3) examining specific autosomal regions containing ROH. For each, we calculated beta coefficients and standard errors using logistic regression and combined estimates across studies using random-effects meta-analysis.

RESULTS

We discovered positive associations between FROH and CLL (β = 21.1, SE = 4.41, P = 1.6 × 10-6) and FL (β = 11.4, SE = 5.82, P = 0.02) but not DLBCL (P = 1.0) or MZL (P = 0.91). For F3, we observed an association with CLL (β = 27.5, SE = 6.51, P = 2.4 × 10-5). We did not find evidence of associations with specific ROH, suggesting that the associations observed with FROH and F3 for CLL and FL risk were not driven by a single region of homozygosity.

CONCLUSION

Our findings support the role of recessive genetic variation in the etiology of CLL and FL; additional research is needed to identify the specific loci associated with NHL risk.

Author Correction: A case-only study to identify genetic modifiers of breast cancer risk for BRCA1/BRCA2 mutation carriers

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-23162-4

Breast Cancer Risk Factors and Survival by Tumor Subtype: Pooled Analyses from the Breast Cancer Association Consortium

BACKGROUND

It is not known whether modifiable lifestyle factors that predict survival after invasive breast cancer differ by subtype.

METHODS

We analyzed data for 121,435 women diagnosed with breast cancer from 67 studies in the Breast Cancer Association Consortium with 16,890 deaths (8,554 breast cancer specific) over 10 years. Cox regression was used to estimate associations between risk factors and 10-year all-cause mortality and breast cancer-specific mortality overall, by estrogen receptor (ER) status, and by intrinsic-like subtype.

RESULTS

There was no evidence of heterogeneous associations between risk factors and mortality by subtype (P adj > 0.30). The strongest associations were between all-cause mortality and BMI ≥30 versus 18.5-25 kg/m2 [HR (95% confidence interval (CI), 1.19 (1.06-1.34)]; current versus never smoking [1.37 (1.27-1.47)], high versus low physical activity [0.43 (0.21-0.86)], age ≥30 years versus <20 years at first pregnancy [0.79 (0.72-0.86)]; >0-<5 years versus ≥10 years since last full-term birth [1.31 (1.11-1.55)]; ever versus never use of oral contraceptives [0.91 (0.87-0.96)]; ever versus never use of menopausal hormone therapy, including current estrogen-progestin therapy [0.61 (0.54-0.69)]. Similar associations with breast cancer mortality were weaker; for example, 1.11 (1.02-1.21) for current versus never smoking.

CONCLUSIONS

We confirm associations between modifiable lifestyle factors and 10-year all-cause mortality. There was no strong evidence that associations differed by ER status or intrinsic-like subtype.

IMPACT

Given the large dataset and lack of evidence that associations between modifiable risk factors and 10-year mortality differed by subtype, these associations could be cautiously used in prognostication models to inform patient-centered care.

Combined Associations of a Polygenic Risk Score and Classical Risk Factors With Breast Cancer Risk

We evaluated the joint associations between a new 313-variant PRS (PRS313) and questionnaire-based breast cancer risk factors for women of European ancestry, using 72 284 cases and 80 354 controls from the Breast Cancer Association Consortium. Interactions were evaluated using standard logistic regression and a newly developed case-only method for breast cancer risk overall and by estrogen receptor status. After accounting for multiple testing, we did not find evidence that per-standard deviation PRS313 odds ratio differed across strata defined by individual risk factors. Goodness-of-fit tests did not reject the assumption of a multiplicative model between PRS313 and each risk factor. Variation in projected absolute lifetime risk of breast cancer associated with classical risk factors was greater for women with higher genetic risk (PRS313 and family history) and, on average, 17.5% higher in the highest vs lowest deciles of genetic risk. These findings have implications for risk prevention for women at increased risk of breast cancer.

A case-only study to identify genetic modifiers of breast cancer risk for BRCA1/BRCA2 mutation carriers

Breast cancer (BC) risk for BRCA1 and BRCA2 mutation carriers varies by genetic and familial factors. About 50 common variants have been shown to modify BC risk for mutation carriers. All but three, were identified in general population studies. Other mutation carrier-specific susceptibility variants may exist but studies of mutation carriers have so far been underpowered. We conduct a novel case-only genome-wide association study comparing genotype frequencies between 60,212 general population BC cases and 13,007 cases with BRCA1 or BRCA2 mutations. We identify robust novel associations for 2 variants with BC for BRCA1 and 3 for BRCA2 mutation carriers, P < 10-8, at 5 loci, which are not associated with risk in the general population. They include rs60882887 at 11p11.2 where MADD, SP11 and EIF1, genes previously implicated in BC biology, are predicted as potential targets. These findings will contribute towards customising BC polygenic risk scores for BRCA1 and BRCA2 mutation carriers.

A Population-Based Study of Genes Previously Implicated in Breast Cancer

BACKGROUND

Population-based estimates of the risk of breast cancer associated with germline pathogenic variants in cancer-predisposition genes are critically needed for risk assessment and management in women with inherited pathogenic variants.

METHODS

In a population-based case-control study, we performed sequencing using a custom multigene amplicon-based panel to identify germline pathogenic variants in 28 cancer-predisposition genes among 32,247 women with breast cancer (case patients) and 32,544 unaffected women (controls) from population-based studies in the Cancer Risk Estimates Related to Susceptibility (CARRIERS) consortium. Associations between pathogenic variants in each gene and the risk of breast cancer were assessed.

RESULTS

Pathogenic variants in 12 established breast cancer-predisposition genes were detected in 5.03% of case patients and in 1.63% of controls. Pathogenic variants in BRCA1 and BRCA2 were associated with a high risk of breast cancer, with odds ratios of 7.62 (95% confidence interval [CI], 5.33 to 11.27) and 5.23 (95% CI, 4.09 to 6.77), respectively. Pathogenic variants in PALB2 were associated with a moderate risk (odds ratio, 3.83; 95% CI, 2.68 to 5.63). Pathogenic variants in BARD1, RAD51C, and RAD51D were associated with increased risks of estrogen receptor-negative breast cancer and triple-negative breast cancer, whereas pathogenic variants in ATM, CDH1, and CHEK2 were associated with an increased risk of estrogen receptor-positive breast cancer. Pathogenic variants in 16 candidate breast cancer-predisposition genes, including the c.657_661del5 founder pathogenic variant in NBN, were not associated with an increased risk of breast cancer.

CONCLUSIONS

This study provides estimates of the prevalence and risk of breast cancer associated with pathogenic variants in known breast cancer-predisposition genes in the U.S. population. These estimates can inform cancer testing and screening and improve clinical management strategies for women in the general population with inherited pathogenic variants in these genes. (Funded by the National Institutes of Health and the Breast Cancer Research Foundation.).

CYP3A7*1C allele: linking premenopausal oestrone and progesterone levels with risk of hormone receptor-positive breast cancers

BACKGROUND

Epidemiological studies provide strong evidence for a role of endogenous sex hormones in the aetiology of breast cancer. The aim of this analysis was to identify genetic variants that are associated with urinary sex-hormone levels and breast cancer risk.

METHODS

We carried out a genome-wide association study of urinary oestrone-3-glucuronide and pregnanediol-3-glucuronide levels in 560 premenopausal women, with additional analysis of progesterone levels in 298 premenopausal women. To test for the association with breast cancer risk, we carried out follow-up genotyping in 90,916 cases and 89,893 controls from the Breast Cancer Association Consortium. All women were of European ancestry.

RESULTS

For pregnanediol-3-glucuronide, there were no genome-wide significant associations; for oestrone-3-glucuronide, we identified a single peak mapping to the CYP3A locus, annotated by rs45446698. The minor rs45446698-C allele was associated with lower oestrone-3-glucuronide (-49.2%, 95% CI -56.1% to -41.1%, P = 3.1 × 10-18); in follow-up analyses, rs45446698-C was also associated with lower progesterone (-26.7%, 95% CI -39.4% to -11.6%, P = 0.001) and reduced risk of oestrogen and progesterone receptor-positive breast cancer (OR = 0.86, 95% CI 0.82-0.91, P = 6.9 × 10-8).

CONCLUSIONS

The CYP3A7*1C allele is associated with reduced risk of hormone receptor-positive breast cancer possibly mediated via an effect on the metabolism of endogenous sex hormones in premenopausal women.

Proportion of cancer cases and deaths attributable to alcohol consumption by US state, 2013-2016

BACKGROUND

Alcohol consumption is an established risk factor for several cancer types, but there are no contemporary published estimates of the state-level burden of cancer attributed to alcoholic beverage consumption. Such estimates are needed to inform public policy and cancer control efforts. We estimated the proportion and number of incident cancer cases and cancer deaths attributable to alcohol consumption by sex in adults aged ≥30 years in all 50 states and the District of Columbia in 2013-2016.

METHODS

Age-, sex-, and state-specific cancer incidence and mortality data (2013-2016) were obtained from the US Cancer Statistics database. State-level, self-reported age and sex stratified alcohol consumption prevalence was estimated using the 2003-2006 Behavioral Risk Factor Surveillance System surveys and adjusted with state sales data.

RESULTS

The proportion of alcohol-attributable incident cancer cases ranged from 2.9 % (95 % confidence interval: 2.7 %-3.1 %) in Utah to 6.7 % (6.4 %-7.0 %) in Delaware among men and women combined, from 2.7 % (2.5 %-3.0 %) in Utah to 6.3 % (5.9 %-6.7 %) in Hawaii among men, and from 2.7 % (2.4 %-3.0 %) in Utah to 7.7 % (7.2 %-8.3 %) in Delaware among women. The proportion of alcohol-attributable cancer deaths also varied considerably across states: from 1.9 % to 4.5 % among men and women combined, from 2.1% to 5.0% among men, and from 1.4 % to 4.4 % among women. Nationally, alcohol consumption accounted for 75,199 cancer cases and 18,947 cancer deaths annually.

CONCLUSION

Alcohol consumption accounts for a considerable proportion of cancer incidence and mortality in all states. Implementing state-level policies and cancer control efforts to reduce alcohol consumption could reduce this cancer burden.

Breast cancer risk factors by mode of detection among screened women in the Cancer Prevention Study-II

BACKGROUND

Identifying risk factors for women at high risk of symptom-detected breast cancers that were missed by screening would enable targeting of enhanced screening regimens. To this end, we examined associations of breast cancer risk factors by mode of detection in screened women from the Cancer Prevention Study (CPS)-II Nutrition Cohort.

METHODS

Among 77,206 women followed for a median of 14.8 years, 2711 screen-detected and 1281 symptom-detected breast cancer cases were diagnosed. Multivariable-adjusted associations were estimated using joint Cox proportional hazards regression models with person-time calculated contingent on screening.

RESULTS

Factors associated with higher risks of symptom-detected and screen-detected breast cancer included current combined hormone therapy (HT) use (HR 2.07, 95% CI 1.72-2.48 and 1.45, 1.27-1.65, respectively) and history of benign breast disease (1.85, 1.64-2.08 and 1.43, 1.31-1.55, respectively). Current estrogen-only HT use was associated with symptom-detected (1.40, 1.15-1.71) but not screen-detected (0.95, 0.83-1.09) breast cancer. Higher risk of screen-detected but not symptom-detected breast cancer was observed for obese vs. normal body mass index (1.22, 1.01-1.48 and 0.76, 0.56-1.01, respectively), per 3 h/day sitting time (1.10, 1.04-1.16 and 0.97, 0.89-1.06, respectively), and ≥ 2 drinks per day vs. nondrinker (1.40, 1.16-1.69 and 1.27, 0.97-1.66, respectively).

CONCLUSIONS

Differences in risk factors for symptom-detected vs. screen-detected breast cancer were observed and most notably, use of combined and estrogen-only HT and a history of benign breast disease were associated with increased risk of symptomatic detected breast cancer.

IMPACT

If confirmed, these data suggest that such women may benefit from more intensive screening to facilitate early detection.

Association of Body Mass Index With Colorectal Cancer Risk by Genome-Wide Variants

BACKGROUND

Body mass index (BMI) is a complex phenotype that may interact with genetic variants to influence colorectal cancer risk.

METHODS

We tested multiplicative statistical interactions between BMI (per 5 kg/m2) and approximately 2.7 million single nucleotide polymorphisms with colorectal cancer risk among 14 059 colorectal cancer case (53.2% women) and 14 416 control (53.8% women) participants. All analyses were stratified by sex a priori. Statistical methods included 2-step (ie, Cocktail method) and single-step (ie, case-control logistic regression and a joint 2-degree of freedom test) procedures. All statistical tests were two-sided.

RESULTS

Each 5 kg/m2 increase in BMI was associated with higher risks of colorectal cancer, less so for women (odds ratio [OR] = 1.14, 95% confidence intervals [CI] = 1.11 to 1.18; P = 9.75 × 10-17) than for men (OR = 1.26, 95% CI = 1.20 to 1.32; P = 2.13 × 10-24). The 2-step Cocktail method identified an interaction for women, but not men, between BMI and a SMAD7 intronic variant at 18q21.1 (rs4939827; Pobserved = .0009; Pthreshold = .005). A joint 2-degree of freedom test was consistent with this finding for women (joint P = 2.43 × 10-10). Each 5 kg/m2 increase in BMI was more strongly associated with colorectal cancer risk for women with the rs4939827-CC genotype (OR = 1.24, 95% CI = 1.16 to 1.32; P = 2.60 × 10-10) than for women with the CT (OR = 1.14, 95% CI = 1.09 to 1.19; P = 1.04 × 10-8) or TT (OR = 1.07, 95% CI = 1.01 to 1.14; P = .02) genotypes.

CONCLUSION

These results provide novel insights on a potential mechanism through which a SMAD7 variant, previously identified as a susceptibility locus for colorectal cancer, and BMI may influence colorectal cancer risk for women.

Trans-ancestry genome-wide association meta-analysis of prostate cancer identifies new susceptibility loci and informs genetic risk prediction

Prostate cancer is a highly heritable disease with large disparities in incidence rates across ancestry populations. We conducted a multiancestry meta-analysis of prostate cancer genome-wide association studies (107,247 cases and 127,006 controls) and identified 86 new genetic risk variants independently associated with prostate cancer risk, bringing the total to 269 known risk variants. The top genetic risk score (GRS) decile was associated with odds ratios that ranged from 5.06 (95% confidence interval (CI), 4.84-5.29) for men of European ancestry to 3.74 (95% CI, 3.36-4.17) for men of African ancestry. Men of African ancestry were estimated to have a mean GRS that was 2.18-times higher (95% CI, 2.14-2.22), and men of East Asian ancestry 0.73-times lower (95% CI, 0.71-0.76), than men of European ancestry. These findings support the role of germline variation contributing to population differences in prostate cancer risk, with the GRS offering an approach for personalized risk prediction.

Adiposity, metabolites, and colorectal cancer risk: Mendelian randomization study

BACKGROUND

Higher adiposity increases the risk of colorectal cancer (CRC), but whether this relationship varies by anatomical sub-site or by sex is unclear. Further, the metabolic alterations mediating the effects of adiposity on CRC are not fully understood.

METHODS

We examined sex- and site-specific associations of adiposity with CRC risk and whether adiposity-associated metabolites explain the associations of adiposity with CRC. Genetic variants from genome-wide association studies of body mass index (BMI) and waist-to-hip ratio (WHR, unadjusted for BMI; N = 806,810), and 123 metabolites from targeted nuclear magnetic resonance metabolomics (N = 24,925), were used as instruments. Sex-combined and sex-specific Mendelian randomization (MR) was conducted for BMI and WHR with CRC risk (58,221 cases and 67,694 controls in the Genetics and Epidemiology of Colorectal Cancer Consortium, Colorectal Cancer Transdisciplinary Study, and Colon Cancer Family Registry). Sex-combined MR was conducted for BMI and WHR with metabolites, for metabolites with CRC, and for BMI and WHR with CRC adjusted for metabolite classes in multivariable models.

RESULTS

In sex-specific MR analyses, higher BMI (per 4.2 kg/m2) was associated with 1.23 (95% confidence interval (CI) = 1.08, 1.38) times higher CRC odds among men (inverse-variance-weighted (IVW) model); among women, higher BMI (per 5.2 kg/m2) was associated with 1.09 (95% CI = 0.97, 1.22) times higher CRC odds. WHR (per 0.07 higher) was more strongly associated with CRC risk among women (IVW OR = 1.25, 95% CI = 1.08, 1.43) than men (IVW OR = 1.05, 95% CI = 0.81, 1.36). BMI or WHR was associated with 104/123 metabolites at false discovery rate-corrected P ≤ 0.05; several metabolites were associated with CRC, but not in directions that were consistent with the mediation of positive adiposity-CRC relations. In multivariable MR analyses, associations of BMI and WHR with CRC were not attenuated following adjustment for representative metabolite classes, e.g., the univariable IVW OR for BMI with CRC was 1.12 (95% CI = 1.00, 1.26), and this became 1.11 (95% CI = 0.99, 1.26) when adjusting for cholesterol in low-density lipoprotein particles.

CONCLUSIONS

Our results suggest that higher BMI more greatly raises CRC risk among men, whereas higher WHR more greatly raises CRC risk among women. Adiposity was associated with numerous metabolic alterations, but none of these explained associations between adiposity and CRC. More detailed metabolomic measures are likely needed to clarify the mechanistic pathways.

Erythrocyte levels of cadmium and lead and risk of B-cell non-Hodgkin lymphoma and multiple myeloma

Cadmium and lead are persistent environmental toxins that are known or probable carcinogens, based on evidence for causality for nonhematologic cancers. Associations of these metals with risk of non-Hodgkin lymphoma (NHL) and multiple myeloma (MM) are unknown but biologically plausible. To examine the associations of circulating levels of lead and cadmium exposure with risk of B-cell NHL (B-NHL) and multiple myeloma, we conducted a nested case-control study among 299 incident B-cell NHLs and 76 MM cases within the Cancer Prevention Study-II Nutrition Cohort (CPS-II NC). Each case was incidence-density matched to two eligible controls on age, race, sex and blood draw date. Conditional logistic regression was used to estimate relative risks (RR) and 95% confidence intervals (CI) for lymphoid malignancies overall and stratified by subtype. We observed a significant positive association between high erythrocyte lead concentration and risk of lymphoid malignancies overall (RR = 1.16, 95% CI: 1.02-1.33 per 17.6 μg/L (1 standard deviation [SD])) and follicular lymphoma in particular (RR = 1.80, 95% CI: 1.15-2.80 per SD). In contrast, there was no association between erythrocyte cadmium and risk of B-NHL (RR = 0.89, 95% CI: 0.75-1.06 per 0.37 μg/L [1 SD]), or any B-NHL subtypes; but a strong inverse association with MM risk (RR = 0.59, 95% CI: 0.38-0.89, per SD). Results from our study suggest a positive association between erythrocyte lead level and risk of lymphoid malignancies and a possible inverse association between cadmium and myeloma. Additional research is needed to confirm and further explore these findings.

Joint associations of physical activity and body mass index with the risk of established excess body fatness-related cancers among postmenopausal women

PURPOSE

Excess body fatness and physical activity independently influence the risk of several types of cancer. However, few studies have examined whether physical activity mitigates the excess risk associated with higher body mass index (BMI).

METHODS

We examined the individual and joint associations between BMI (kg/m²) and leisure-time moderate-to-vigorous physical activity (MVPA, MET-hours/week) with the risk of three established excess body fatness-related cancers (breast, colon, and endometrial) among 43,795 postmenopausal women in the Cancer Prevention Study II (CPS-II) Nutrition Cohort (1992/1993-2015). Further exclusions for women without an intact uterus resulted in 31,805 women for endometrial cancer analyses. Multivariable Cox proportional hazards regression was used to calculate hazard ratio (HR) and 95% confidence intervals (CIs) with interaction terms to assess multiplicative interaction. The relative excess risk due to interaction (RERI) was calculated to assess additive interaction.

RESULTS

BMI and MVPA were individually associated with breast and endometrial cancer risk, but only BMI was associated with colon cancer risk. In joint analyses, increasing levels of MVPA did not lower the risk of these cancers among obese women. For example, compared to the common referent (BMI 18.5- < 25 kg/m², MVPA > 0- < 7.5 MET-hours/week), BMI ≥ 30 kg/m² was associated with a higher risk of breast cancer among women with low MVPA (> 0-< 7.5 MET-hours/week: HR = 1.42, 95% CI: 1.22 - 1.67) and high MVPA (≥ 15 MET-hours/week: HR = 1.53, 95% CI: 1.25 - 1.87; RERI = 0.20, 95% CI: -0.14, 0.54, multiplicative P_interaction = 0.64).

CONCLUSION

Our results do not support the hypothesis that leisure-time physical activity mitigates the excess risk associated with higher BMI for risk of breast, endometrial, or colon cancer among postmenopausal women.

Research Participants' Perspectives on Using an Electronic Portal for Engagement and Data Collection: Focus Group Results From a Large Epidemiologic Cohort

Background

Epidemiologic cohort studies have begun to leverage electronic research participant portals to facilitate data collection, integrate wearable technologies, lower costs, and engage participants. However, little is known about the acceptability of portal use by research participants.

Objective

The aim of this study is to conduct focus groups among a sample of Cancer Prevention Study-3 (CPS-3) participants to better understand their preferences and concerns about research portals.

Methods

CPS-3 participants were stratified based on sex, race and ethnicity, age, and cancer status, and randomly invited to participate. Focus groups used an exploratory case design with semistructured guides to prompt discussion. Using a constant comparison technique, transcripts were assigned codes to identify themes.

Results

Participants (31/59, 52% women; 52/59, 88% White/non-Latinx) were favorably disposed toward using a research participant portal to take surveys, communicate with the study staff, and upload data. Most participants indicated that a portal would be beneficial and convenient but expressed concerns over data safety. Participants stressed the importance of an easy-to-use and trustworthy portal that is compatible with mobile devices.

Conclusions

In addition to being beneficial to researchers, portals may also benefit participants as long as the portals are secure and simple. Participants believe that portals can provide convenient ways to report data and remain connected to the study.

Associations between reproductive factors and biliary tract cancers in women from the Biliary Tract Cancers Pooling Project

BACKGROUND & AIMS

Gallbladder cancer (GBC) is known to have a female predominance while other biliary tract cancers (BTCs) have a male predominance. However, the role of female reproductive factors in BTC etiology remains unclear.

METHODS

We pooled data from 19 studies of >1.5 million women participating in the Biliary Tract Cancers Pooling Project to examine the associations of parity, age at menarche, reproductive years, and age at menopause with BTC. Associations for age at menarche and reproductive years with BTC were analyzed separately for Asian and non-Asian women. Hazard ratios (HRs) and 95% CIs were estimated using Cox proportional hazards models, stratified by study.

RESULTS

During 21,681,798 person-years of follow-up, 875 cases of GBC, 379 of intrahepatic bile duct cancer (IHBDC), 450 of extrahepatic bile duct cancer (EHBDC), and 261 of ampulla of Vater cancer (AVC) occurred. High parity was associated with risk of GBC (HR ≥5 vs. 0 births 1.72; 95% CI 1.25-2.38). Age at menarche (HR per year increase 1.15; 95% CI 1.06-1.24) was associated with GBC risk in Asian women while reproductive years were associated with GBC risk (HR per 5 years 1.13; 95% CI 1.04-1.22) in non-Asian women. Later age at menarche was associated with IHBDC (HR 1.19; 95% CI 1.09-1.31) and EHBDC (HR 1.11; 95% CI 1.01-1.22) in Asian women only.

CONCLUSION

We observed an increased risk of GBC with increasing parity. Among Asian women, older age at menarche was associated with increased risk for GBC, IHBDC, and EHBDC, while increasing reproductive years was associated with GBC in non-Asian women. These results suggest that sex hormones have distinct effects on cancers across the biliary tract that vary by geography.

LAY SUMMARY

Our findings show that the risk of gallbladder cancer is increased among women who have given birth (especially women with 5 or more children). In women from Asian countries, later age at menarche increases the risk of gallbladder cancer, intrahepatic bile duct cancer and extrahepatic bile duct cancer. We did not see this same association in women from Western countries. Age at menopause was not associated with the risk of any biliary tract cancers.

A Large Cohort Study of Body Mass Index and Pancreatic Cancer by Smoking Status

BACKGROUND

Some evidence suggests the association between body mass index (BMI) and pancreatic cancer risk is weaker among current smokers than among never smokers.

METHODS

We examined the association between BMI and pancreatic cancer mortality among adults who reported smoking status at enrollment into Cancer Prevention Study-II in 1982, including 420,543 never smokers, 282,244 former cigarette smokers, and 219,885 current cigarette smokers. After excluding the first 3 years of follow-up to reduce reverse causation, we calculated multivariable-adjusted hazard ratios (HR).

RESULTS

During the full follow-up period from 1985 to 2014, 7,904 participants died of pancreatic cancer. The HR per 5 BMI units was lower among current smokers [HR = 1.14; 95% confidence interval (CI), 1.07-1.20] than never smokers (HR = 1.22; 95% CI, 1.17-1.27), although this difference was not statistically significant (P = 0.06). BMI was significantly less strongly associated with pancreatic cancer mortality among current smokers reporting ≥20 cigarettes/day (HR = 1.10; 95% CI, 1.03-1.18) than among never smokers. During follow-up within 10 years of enrollment, when current smokers at enrollment were the most likely to have still been smoking, BMI was not associated with pancreatic cancer mortality among current smokers (HR = 1.02; 95% CI, 0.90-1.16, P = 0.03 for difference between current and never smokers). BMI HRs were similar among former and never smokers.

CONCLUSIONS

These results support a weaker association between BMI and pancreatic cancer among current smokers than among never smokers.

IMPACT

In populations with low smoking prevalence, the pancreatic cancer burden due to BMI is likely to be higher than that predicted by risk estimates from studies including substantial numbers of smokers.

Sustained Weight Loss and Risk of Breast Cancer in Women 50 Years and Older: A Pooled Analysis of Prospective Data

BACKGROUND

Excess body weight is an established cause of postmenopausal breast cancer, but it is unknown if weight loss reduces risk.

METHODS

Associations between weight change and risk of breast cancer were examined among women aged 50 years and older in the Pooling Project of Prospective Studies of Diet and Cancer. In 10 cohorts, weight assessed on three surveys was used to examine weight change patterns over approximately 10 years (interval 1 median = 5.2 years; interval 2 median = 4.0 years). Sustained weight loss was defined as no less than 2 kg lost in interval 1 that was not regained in interval 2. Among 180 885 women, 6930 invasive breast cancers were identified during follow-up.

RESULTS

Compared with women with stable weight (±2 kg), women with sustained weight loss had a lower risk of breast cancer. This risk reduction was linear and specific to women not using postmenopausal hormones (>2-4.5 kg lost: hazard ratio [HR] = 0.82, 95% confidence interval [CI] = 0.70 to 0.96; >4.5-<9 kg lost: HR = 0.75, 95% CI = 0.63 to 0.90; ≥9 kg lost: HR = 0.68, 95% CI = 0.50 to 0.93). Women who lost at least 9 kg and gained back some (but not all) of it were also at a lower risk of breast cancer. Other patterns of weight loss and gain over the two intervals had a similar risk of breast cancer to women with stable weight.

CONCLUSIONS

These results suggest that sustained weight loss, even modest amounts, is associated with lower breast cancer risk for women aged 50 years and older. Breast cancer prevention may be a strong weight-loss motivator for the two-thirds of American women who are overweight or obese.

Abstract PR07: Device-based, objective measurement of physical activity and sedentary behavior in a large U.S. cohort

Physical activity guidelines state that adults should engage in at least 150 minutes of moderate or 75 minutes of vigorous intensity activity per week and limit time spent sitting. Guidelines are based largely on self-reported data of usual amounts of physical activity and sitting time, as self-report is a feasible and cost-effective method for assessment in large epidemiologic studies. However, self-reported survey measures largely focus on moderate-to-vigorous intensity physical activity (MVPA) and total sitting time, and they are subject to various sources of error. The American Cancer Society’s Cancer Prevention Study-3 (CPS-3) is a large, nationwide, prospective cohort of approximately 304,000 participants recruited from 2006-2013. Among 751 randomly selected CPS-3 participants, seven-day accelerometer data were collected at two-time points approximately 6 months apart in 2015/2016 to assess convergent validity of the CPS-3 physical activity survey data. The average number of wear days was excellent (6.6). Vigorous activity (r=0.75) was reported more accurately than light activity (r=0.31); sedentary time also showed reasonable validity (r=0.63). While CPS-3 and other cohort surveys have acceptable validity and are suitable for categorizing participants according to overall activity level, they do not allow for detailed examination of bouts, patterns, or intensity of different activities, especially in terms of measuring light-intensity activity where most active time is spent. Thus, some large cohorts have collected or are collecting accelerometer data on subpopulations to use for calibrating self-reported measures and for examining objective physical activity in relation to health outcomes. We are initiating collection of accelerometer data from a subcohort of at least 20,000 participants. We aim to oversample for men and racial/ethnic minorities as most previous accelerometry studies included predominantly white women. Participants will be sent an accelerometer (ActiGraph GT3x) with a brief survey/wear-time log and asked to wear the device for a maximum of seven days during all waking hours. Through a series of prediction models, the CPS-3 survey will be trained against a smaller subset of accelerometer data to improve the interpretability, accuracy, and precision of CPS-3 sedentary time and PA survey data. Associations of accelerometer-based physical activity with various outcomes will also be conducted. Through the quantifiable assessment of activity at different intensities, bout lengths, and patterns, we will be well positioned to understand dose-response of physical activity and sedentary time in relation to health and better inform public health guidelines. CPS-3 will not only add to the growing number of cohorts with device-based measures but also can uniquely contribute to gaps in the research with its younger age range, inclusion of men and women, and geographic as well as racial/ethnic diversity.

This abstract is also being presented as Poster A33.

Citation Format: Alpa V. Patel, Erika Rees-Punia, Susan M. Gapstur. Device-based, objective measurement of physical activity and sedentary behavior in a large U.S. cohort [abstract]. In: Proceedings of the AACR Special Conference on Modernizing Population Sciences in the Digital Age; 2019 Feb 19-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(9 Suppl):Abstract nr PR07.

A Germline Variant at 8q24 Contributes to Familial Clustering of Prostate Cancer in Men of African Ancestry

Although men of African ancestry have a high risk of prostate cancer (PCa), no genes or mutations have been identified that contribute to familial clustering of PCa in this population. We investigated whether the African ancestry-specific PCa risk variant at 8q24, rs72725854, is enriched in men with a PCa family history in 9052 cases, 143 cases from high-risk families, and 8595 controls of African ancestry. We found the risk allele to be significantly associated with earlier age at diagnosis, more aggressive disease, and enriched in men with a PCa family history (32% of high-risk familial cases carried the variant vs 23% of cases without a family history and 12% of controls). For cases with two or more first-degree relatives with PCa who had at least one family member diagnosed at age <60 yr, the odds ratios for TA heterozygotes and TT homozygotes were 3.92 (95% confidence interval [CI] = 2.13-7.22) and 33.41 (95% CI = 10.86-102.84), respectively. Among men with a PCa family history, the absolute risk by age 60 yr reached 21% (95% CI = 17-25%) for TA heterozygotes and 38% (95% CI = 13-65%) for TT homozygotes. We estimate that in men of African ancestry, rs72725854 accounts for 32% of the total familial risk explained by all known PCa risk variants. PATIENT SUMMARY: We found that rs72725854, an African ancestry-specific risk variant, is more common in men with a family history of prostate cancer and in those diagnosed with prostate cancer at younger ages. Men of African ancestry may benefit from the knowledge of their carrier status for this genetic risk variant to guide decisions about prostate cancer screening.

Germline Sequencing DNA Repair Genes in 5545 Men With Aggressive and Nonaggressive Prostate Cancer

BACKGROUND

There is an urgent need to identify factors specifically associated with aggressive prostate cancer (PCa) risk. We investigated whether rare pathogenic, likely pathogenic, or deleterious (P/LP/D) germline variants in DNA repair genes are associated with aggressive PCa risk in a case-case study of aggressive vs nonaggressive disease.

METHODS

Participants were 5545 European-ancestry men, including 2775 nonaggressive and 2770 aggressive PCa cases, which included 467 metastatic cases (16.9%). Samples were assembled from 12 international studies and germline sequenced together. Rare (minor allele frequency < 0.01) P/LP/D variants were analyzed for 155 DNA repair genes. We compared single variant, gene-based, and DNA repair pathway-based burdens by disease aggressiveness. All statistical tests are 2-sided.

RESULTS

BRCA2 and PALB2 had the most statistically significant gene-based associations, with 2.5% of aggressive and 0.8% of nonaggressive cases carrying P/LP/D BRCA2 alleles (odds ratio [OR] = 3.19, 95% confidence interval [CI] = 1.94 to 5.25, P = 8.58 × 10-7) and 0.65% of aggressive and 0.11% of nonaggressive cases carrying P/LP/D PALB2 alleles (OR = 6.31, 95% CI = 1.83 to 21.68, P = 4.79 × 10-4). ATM had a nominal association, with 1.6% of aggressive and 0.8% of nonaggressive cases carrying P/LP/D ATM alleles (OR = 1.88, 95% CI = 1.10 to 3.22, P = .02). In aggregate, P/LP/D alleles within 24 literature-curated candidate PCa DNA repair genes were more common in aggressive than nonaggressive cases (carrier frequencies = 14.2% vs 10.6%, respectively; P = 5.56 × 10-5). However, this difference was non-statistically significant (P = .18) on excluding BRCA2, PALB2, and ATM. Among these 24 genes, P/LP/D carriers had a 1.06-year younger diagnosis age (95% CI = -1.65 to 0.48, P = 3.71 × 10-4).

CONCLUSIONS

Risk conveyed by DNA repair genes is largely driven by rare P/LP/D alleles within BRCA2, PALB2, and ATM. These findings support the importance of these genes in both screening and disease management considerations.

Outdoor air pollution and cancer: An overview of the current evidence and public health recommendations

Outdoor air pollution is a major contributor to the burden of disease worldwide. Most of the global population resides in places where air pollution levels, because of emissions from industry, power generation, transportation, and domestic burning, considerably exceed the World Health Organization's health-based air-quality guidelines. Outdoor air pollution poses an urgent worldwide public health challenge because it is ubiquitous and has numerous serious adverse human health effects, including cancer. Currently, there is substantial evidence from studies of humans and experimental animals as well as mechanistic evidence to support a causal link between outdoor (ambient) air pollution, and especially particulate matter (PM) in outdoor air, with lung cancer incidence and mortality. It is estimated that hundreds of thousands of lung cancer deaths annually worldwide are attributable to PM air pollution. Epidemiological evidence on outdoor air pollution and the risk of other types of cancer, such as bladder cancer or breast cancer, is more limited. Outdoor air pollution may also be associated with poorer cancer survival, although further research is needed. This report presents an overview of outdoor air pollutants, sources, and global levels, as well as a description of epidemiological evidence linking outdoor air pollution with cancer incidence and mortality. Biological mechanisms of air pollution-derived carcinogenesis are also described. This report concludes by summarizing public health/policy recommendations, including multilevel interventions aimed at individual, community, and regional scales. Specific roles for medical and health care communities with regard to prevention and advocacy and recommendations for further research are also described.

Coffee Consumption and Invasive Breast Cancer Incidence among Postmenopausal Women in the Cancer Prevention Study-II Nutrition Cohort

BACKGROUND

There is limited evidence of a potential inverse association between coffee, particularly caffeinated coffee, consumption and postmenopausal breast cancer risk, and few studies have examined this association by tumor hormone receptor status. To provide further evidence, we examined total, caffeinated, and decaffeinated coffee consumption in relation to postmenopausal invasive breast cancer incidence overall, and by tumor estrogen receptor (ER) and/or progesterone receptor (PR) subtype.

METHODS

Among 57,075 postmenopausal women in the Cancer Prevention Study-II Nutrition Cohort who were cancer free and reported coffee intake in 1999, we identified 2,980 women diagnosed with invasive breast cancer during follow-up through June 2015. Multivariable-adjusted Cox proportional hazards regression was used to compute hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

Neither total, caffeinated, nor decaffeinated coffee consumption was associated with invasive breast cancer risk; HRs (95% CIs) comparing consumption of ≥2 cups per day with <1 cup per month were 0.99 (0.89-1.11), 0.96 (0.87-1.06), and 1.06 (0.95-1.19), respectively. Similarly, coffee consumption was not associated with risk of hormone receptor-positive (ER⁺ or PR⁺) or hormone receptor-negative (ER^- and PR^-) breast tumors.

CONCLUSIONS

These findings do not support an association between coffee consumption and invasive breast cancer risk among postmenopausal women.

IMPACT

This large prospective study contributes to the limited evidence on coffee consumption and breast cancer risk, finding no association overall or by tumor receptor subtype.

Abstract 1051: Association of Toxoplasma gondii antibodies in blood and risk of glioma

Background: Brain and other nervous system cancers are relatively rare but remain the eighth most common cancer among persons aged 40 years and older. Gliomas are the most common type of primary brain cancer, have poor overall survival, and their etiology remains unclear. Toxoplasma gondii (T. gondii) is a common protozoan parasite and has been reported to cause glioma-like tumors in animals. In humans, the infection shows affinity to neural tissue and may lead to local necrosis and inflammation, and the formation of cysts in the brain from which infection may be reactivated according to host immunologic status. Previous ecologic and case-control studies have suggested an association with increased risk of gliomas in humans infected with T. gondii, but retrospective collection of exposure information from brain tumor patients is challenging. In this study, we assessed the relation between prediagnostic T. gondii antibodies and risk of glioma in two prospective cohorts.

Methods: Cases and matched controls were selected from the American Cancer Society's Cancer Prevention Study-II (CPSII) and the Norwegian Cancer Registry's Janus Serum Bank (Janus). To avoid potential effects of preclinical disease on serum antibody titers, the study was restricted to cases with blood collected a minimum of 3 years (in CPSII) or 5 years (in Janus) prior to glioma diagnosis. Using a multiplex serological assay, blood samples were analyzed simultaneously for antibodies to two surface antigens (p22 and sag1) specific to T. gondii which represent acute parasitic infection. Samples were considered positive for T. gondii infection if either antibody was positive, defined using assay-specific cutoffs unique to each antigen. Conditional logistic regression was used to calculate odds ratios for each cohort separately.

Results: A total of 37 cases and 74 controls were included from CPSII while 323 cases and 323 controls were included from Janus. The median age at blood draw was 71 years in CPSII and 41.1 years in Janus. In both cohorts, there was a suggestive increased risk of glioma among those infected with T. gondii. The association was strongest for gliomas diagnosed in approximately the first decade after blood collection in both Janus (OR: 2.50; 95% CI: 0.97-6.44, p = 0.058) and CPSII (OR: 2.71; 95% CI: 0.95-7.62, p = 0.060), with similar results observed in high grade glioblastoma (CPSII N = 27, OR: 2.31, 95% CI: 0.71-7.47; Janus N = 61, OR: 2.25, 95% CI: 0.70-7.31) and lower grade gliomas (Janus N = 47, OR: 3.00, 95% CI: 0.61-15).

Conclusions: Blood antibody levels from two prospective cohorts indicate a possible association between T. gondii infection and increased risk of glioma. The association was strongest in the first decade after antibody measurement. The consistency, magnitude, and direction of the association support the need for pooled analyses with larger case numbers for definitive investigation.

Citation Format: James M. Hodge, Anna E. Coghill, Youngchul Kim, Noemi Bender, Stephanie Smith-Warner, Tom K. Grimsrud, Susan M. Gapstur, Tim Waterboer, Lauren R. Teras, Kathleen M. Egan. Association of Toxoplasma gondii antibodies in blood and risk of glioma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1051.

Relationship Between Muscle-Strengthening Activity and Cause-Specific Mortality in a Large US Cohort

INTRODUCTION

Muscle-strengthening activity (MSA) has beneficial effects on hypertension, glucose homeostasis, and other health conditions; however, its association with mortality is not as well understood.

METHODS

We analyzed data from the Cancer Prevention Study-II Nutrition Cohort (data collection 1982-2014), a prospective US cohort that consisted of 72,462 men and women who were free of major chronic diseases; 18,034 of the cohort died during 13 years of follow-up (2001-2014). We used Cox proportional hazards modeling, controlling for various potential confounding factors, to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for MSA (none, >0 to <1 h/wk, 1 to <2 h/wk, and ≥2 h/wk) in relation to mortality risk, independent of and in combination with aerobic physical activity.

RESULTS

The association between MSA and mortality appeared to be nonlinear (quadratic trend P value, <.001). After multivariable adjustment and comparison with no MSA, engaging in less than 2 hours per week of MSA was associated with lowered all-cause mortality (>0 to <1 h/wk: HR = 0.88, 95% CI, 0.82-0.94; 1 to <2 h/wk: HR = 0.90, 95% CI, 0.84-0.97), but engaging in 2 or more hours per week was not associated with reduced risk (HR = 1.01; 95% CI, 0.92-1.09). Associations were similar but not significant for cancer mortality. Engaging in >0 to <1 hr/wk of MSA was associated with a 19% lower risk (HR = 0.81; 95% CI, 0.71-0.92) of cardiovascular disease mortality, but more time spent in MSA was not associated with reduced risk (quadratic trend P value =.005). Associations did not vary by amount of moderate-to-vigorous aerobic physical activity.

CONCLUSION

Engaging in ≥2 hours per week of MSA was associated with lower all-cause mortality, independent of aerobic activity. Reasons for the lack of association with higher amounts of MSA are unclear. Our findings support recommending muscle-strengthening activities for overall health.

American Cancer Society guideline for diet and physical activity for cancer prevention

The American Cancer Society (ACS) publishes the Diet and Physical Activity Guideline to serve as a foundation for its communication, policy, and community strategies and, ultimately, to affect dietary and physical activity patterns among Americans. This guideline is developed by a national panel of experts in cancer research, prevention, epidemiology, public health, and policy, and reflects the most current scientific evidence related to dietary and activity patterns and cancer risk. The ACS guideline focuses on recommendations for individual choices regarding diet and physical activity patterns, but those choices occur within a community context that either facilitates or creates barriers to healthy behaviors. Therefore, this committee presents recommendations for community action to accompany the 4 recommendations for individual choices to reduce cancer risk. These recommendations for community action recognize that a supportive social and physical environment is indispensable if individuals at all levels of society are to have genuine opportunities to choose healthy behaviors. This 2020 ACS guideline is consistent with guidelines from the American Heart Association and the American Diabetes Association for the prevention of coronary heart disease and diabetes as well as for general health promotion, as defined by the 2015 to 2020 Dietary Guidelines for Americans and the 2018 Physical Activity Guidelines for Americans.

Exogenous hormone use, reproductive factors and risk of intrahepatic cholangiocarcinoma among women: results from cohort studies in the Liver Cancer Pooling Project and the UK Biobank

BACKGROUND

Intrahepatic cholangiocarcinoma (ICC) arises from cholangiocytes in the intrahepatic bile duct and is the second most common type of liver cancer. Cholangiocytes express both oestrogen receptor-α and -β, and oestrogens positively modulate cholangiocyte proliferation. Studies in women and men have reported higher circulating oestradiol is associated with increased ICC risk, further supporting a hormonal aetiology. However, no observational studies have examined the associations between exogenous hormone use and reproductive factors, as proxies of endogenous hormone levels, and risk of ICC.

METHODS

We harmonised data from 1,107,498 women who enroled in 12 North American-based cohort studies (in the Liver Cancer Pooling Project, LCPP) and the UK Biobank between 1980-1998 and 2006-2010, respectively. Cox proportional hazards regression models were used to generate hazard ratios (HR) and 95% confidence internals (CI). Then, meta-analytic techniques were used to combine the estimates from the LCPP (n = 180 cases) and the UK Biobank (n = 57 cases).

RESULTS

Hysterectomy was associated with a doubling of ICC risk (HR = 1.98, 95% CI: 1.27-3.09), compared to women aged 50-54 at natural menopause. Long-term oral contraceptive use (9+ years) was associated with a 62% increased ICC risk (HR = 1.62, 95% CI: 1.03-2.55). There was no association between ICC risk and other exogenous hormone use or reproductive factors.

CONCLUSIONS

This study suggests that hysterectomy and long-term oral contraceptive use may be associated with an increased ICC risk.

Transcriptome-wide association study of breast cancer risk by estrogen-receptor status

Previous transcriptome-wide association studies (TWAS) have identified breast cancer risk genes by integrating data from expression quantitative loci and genome-wide association studies (GWAS), but analyses of breast cancer subtype-specific associations have been limited. In this study, we conducted a TWAS using gene expression data from GTEx and summary statistics from the hitherto largest GWAS meta-analysis conducted for breast cancer overall, and by estrogen receptor subtypes (ER+ and ER-). We further compared associations with ER+ and ER- subtypes, using a case-only TWAS approach. We also conducted multigene conditional analyses in regions with multiple TWAS associations. Two genes, STXBP4 and HIST2H2BA, were specifically associated with ER+ but not with ER- breast cancer. We further identified 30 TWAS-significant genes associated with overall breast cancer risk, including four that were not identified in previous studies. Conditional analyses identified single independent breast-cancer gene in three of six regions harboring multiple TWAS-significant genes. Our study provides new information on breast cancer genetics and biology, particularly about genomic differences between ER+ and ER- breast cancer.

Germline HOXB13 mutations p.G84E and p.R217C do not confer an increased breast cancer risk

In breast cancer, high levels of homeobox protein Hox-B13 (HOXB13) have been associated with disease progression of ER-positive breast cancer patients and resistance to tamoxifen treatment. Since HOXB13 p.G84E is a prostate cancer risk allele, we evaluated the association between HOXB13 germline mutations and breast cancer risk in a previous study consisting of 3,270 familial non-BRCA1/2 breast cancer cases and 2,327 controls from the Netherlands. Although both recurrent HOXB13 mutations p.G84E and p.R217C were not associated with breast cancer risk, the risk estimation for p.R217C was not very precise. To provide more conclusive evidence regarding the role of HOXB13 in breast cancer susceptibility, we here evaluated the association between HOXB13 mutations and increased breast cancer risk within 81 studies of the international Breast Cancer Association Consortium containing 68,521 invasive breast cancer patients and 54,865 controls. Both HOXB13 p.G84E and p.R217C did not associate with the development of breast cancer in European women, neither in the overall analysis (OR = 1.035, 95% CI = 0.859-1.246, P = 0.718 and OR = 0.798, 95% CI = 0.482-1.322, P = 0.381 respectively), nor in specific high-risk subgroups or breast cancer subtypes. Thus, although involved in breast cancer progression, HOXB13 is not a material breast cancer susceptibility gene.

Coffee consumption and risk of colorectal cancer in the Cancer Prevention Study-II Nutrition Cohort

BACKGROUND

The association between coffee consumption and colorectal cancer risk generally appears null, but recent evidence suggests that risk may vary by coffee type. We examined associations of caffeinated and decaffeinated coffee intake with colorectal cancer risk overall and with colon and rectum separately, among older U.S. men and women.

METHODS

In 1999, 47,010 men and 60,051 women with no previous diagnosis of cancer, aged 47-96 years, in the Cancer Prevention Study-II Nutrition Cohort completed a food frequency questionnaire that assessed caffeinated and decaffeinated coffee intake; consumption was updated in 2003. A total of 1829 colorectal cancer cases were verified through June 2015. Cox proportional hazards regression was used to estimate multivariable-adjusted hazard rate ratios (HRs) and 95% confidence intervals (CIs), adjusting for smoking history, alcohol, caffeinated/decaffeinated coffee intake (depending on the model), and other colorectal cancer risk factors.

RESULTS

Consumption of ≥2 cups/day of decaffeinated coffee, compared to no decaffeinated coffee, was associated with lower risk of overall colorectal cancer (HR = 0.82, 95% CI: 0.69-0.96, P-trend = 0.04), colon cancer (HR = 0.82, 95% CI: 0.69-0.99, P-trend = 0.05) and rectal cancer (HR = 0.63, 95% CI: 0.40-0.99, P-trend = 0.17). Consumption of ≥2 cups/day of caffeinated coffee was associated with higher risk of rectal cancer (HR = 1.37, 95% CI: 0.99-1.89, P-trend = 0.04), but not with colorectal or colon cancer.

CONCLUSION

In this prospective study, higher intake of decaffeinated coffee was associated with lower risk of colorectal, colon, and rectal cancers. Further study on associations of caffeinated and decaffeinated coffee with colorectal cancer risk by subsite is needed.

Genome-wide association study identifies 32 novel breast cancer susceptibility loci from overall and subtype-specific analyses

Breast cancer susceptibility variants frequently show heterogeneity in associations by tumor subtype1-3. To identify novel loci, we performed a genome-wide association study including 133,384 breast cancer cases and 113,789 controls, plus 18,908 BRCA1 mutation carriers (9,414 with breast cancer) of European ancestry, using both standard and novel methodologies that account for underlying tumor heterogeneity by estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 status and tumor grade. We identified 32 novel susceptibility loci (P < 5.0 × 10-8), 15 of which showed evidence for associations with at least one tumor feature (false discovery rate < 0.05). Five loci showed associations (P < 0.05) in opposite directions between luminal and non-luminal subtypes. In silico analyses showed that these five loci contained cell-specific enhancers that differed between normal luminal and basal mammary cells. The genetic correlations between five intrinsic-like subtypes ranged from 0.35 to 0.80. The proportion of genome-wide chip heritability explained by all known susceptibility loci was 54.2% for luminal A-like disease and 37.6% for triple-negative disease. The odds ratios of polygenic risk scores, which included 330 variants, for the highest 1% of quantiles compared with middle quantiles were 5.63 and 3.02 for luminal A-like and triple-negative disease, respectively. These findings provide an improved understanding of genetic predisposition to breast cancer subtypes and will inform the development of subtype-specific polygenic risk scores.