Breast Cancer Risk Research Articles

Mammographic density and breast cancer risk among Black American women.

High mammographic density is a well-established risk factor for breast cancer; however, data from Black women are limited. It is largely unknown how mammographic density is associated with breast cancer subtypes among Black women. We examined the association between percent mammographic density (PMD) and breast cancer risk among participants in the Black Women's Health Study. Digital screening mammograms were available for 363 cases and 5541 non-cases. Cumulus software was used to assess PMD. We used inverse probability of sampling weights and Cox proportional hazards models, adjusted for age and body mass index, to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) overall and by age at mammography and estrogen receptor (ER) status of the breast tumors. Multivariable models included additional breast cancer risk factors. Tests of statistical significance were 2-sided. In simple models, women in the highest quartile of PMD had 53% increased odds of breast cancer compared to those in the lowest quartile (HR 1.53; 95% CI: 1.11, 2.11). HRs were 1.37 (95% CI: 0.83, 2.24) among women <55 years of age and 1.68 (95% CI: 1.10, 2.56) among women aged ≥55 years. HRs were 1.49 (95% CI: 1.02, 2.16) for ER+ cancer and 1.45 (95% CI: 0.73, 2.87) for ER- cancer. Associations were largely unchanged in multivariable models. In this study of U.S. Black women, higher PMD was associated with ER+ and ER- breast cancer risk. Findings from this study reinforce the importance of breast density as a risk factor for breast cancer in Black women.

Phenotypic evaluation of deep learning models for classifying germline variant pathogenicity.

Deep learning models for predicting variant pathogenicity have not been thoroughly evaluated on real-world clinical phenotypes. Here, we apply state-of-the-art pathogenicity prediction models to hereditary breast cancer gene variants in UK Biobank participants. Model predictions for missense variants in BRCA1, BRCA2 and PALB2, but not ATM and CHEK2, were associated with breast cancer risk. However, deep learning models had limited clinical utility when specifically applied to variants of uncertain significance.

Association between radiation therapy for primary endometrial cancer and risk of second primary malignancies: a retrospective cohort study

Our objective was to evaluate the association of adjuvant radiation therapy (RT) to subsequent second primary malignancies (SPMs) in endometrial cancer survivors. Patients with endometrial cancer as their first malignancy were identified from 8 registries of the Surveillance, Epidemiology, and End Results (SEER) database. SPMs were defined as any type of primary malignancy that occurred more than 12 months after the diagnosis of endometrial cancer. Fine-Gray competing risk regression and Poisson regression were used to evaluate the radiotherapy-associated risk (RR) for SPMs. The Kaplan-Meier method was applied to assess the survival outcomes of endometrial cancer patients. Of 62,108 endometrial cancer patients,16,846 patients (27.12%) were in the RT group, and 45,262 patients (72.88%) were in the no-RT group. During the 30-year follow-up period, the cumulative incidence of SPMs was 20.9% and 19.7% in each group, respectively. In both multivariable competing risk regression analysis and Poisson regression analysis, adjuvant RT was found to be associated with a higher risk of developing colon and rectum cancer (adjusted hazard ratio (HR), 1.29; 95% confidence interval (CI), 1.12–1.50; P < 0.001; adjusted RR, 1.29; 95% CI, 1.11–1.49; P < 0.001), lung and bronchus cancer (adjusted HR, 1.27; 95% CI, 1.08–1.50; P = 0.004; adjusted RR, 1.26; 95% CI, 1.07–1.49; P = 0.005), vulva cancer (adjusted HR, 1.72; 95% CI, 1.04–2.85; P = 0.036; adjusted RR, 1.74; 95% CI, 1.03–2.88; P = 0.035), urinary bladder cancer (adjusted HR, 1.86; 95% CI, 1.41–2.46; P < 0.001; adjusted RR, 1.85; 95% CI, 1.40–2.44; P < 0.001), and non-Hodgkin lymphoma (adjusted HR, 1.37; 95% CI, 1.06–1.77; P = 0.016; adjusted RR, 1.37; 95% CI, 1.05–1.76; P = 0.017). However, a slightly decreased risk of breast cancer was observed in patients who underwent adjuvant RT (adjusted HR, 0.89; 95% CI, 0.80–0.98; P = 0.021; adjusted RR, 0.88; 95% CI, 0.80–0.98; P = 0.020). The RR for colon and rectum cancer decreased with age and elevated with increasing latency since endometrial cancer diagnosis, and the RR for urinary bladder cancer showed a similar tendency with latency. SPMs can significantly impair the survival outcomes of primary endometrial cancer survivors. Our findings suggest that adjuvant RT for endometrial cancer patients increases the risk of non-Hodgkin lymphoma and several types of solid cancer. Long-term surveillance of these patients should be recommended for detecting SPMs.

The p53/miRNA Axis in Breast Cancer.

One of the main health issues in the modern world is cancer, with breast cancer (BC) as one of the most common types of malignancies. Different environmental and genetic risk factors are involved in the development of BC. One of the primary genes implicated in cancer development is the p53 gene, which is also known as the "gatekeeper" gene. p53 is involved in cancer development by interacting with numerous pathways and signaling factors, including microRNAs (miRNAs). miRNAs are small noncoding RNA molecules that regulate gene expression by binding to the 3' untranslated region of target mRNAs, resulting in their translational inhibition or degradation. If the p53 gene is mutated or degraded, it can contribute to the risk of BC by disrupting the expression of miRNAs. Similarly, the disruption of miRNAs causes the negative regulation of p53. Therefore, the p53/miRNA axis is a crucial pathway in the progression or prevention of BC, and understanding the regulation and function of this pathway may contribute to the development of new therapeutic strategies to help treat BC.

Plasma C-peptide mammographic features and risk of breast cancer

Our study in the Nurses’ Health Study (NHS) and NHS2, a nested case-control study with 1260 cases and 2221 controls, investigated the association between C-peptide levels, mammographic density (MD) parameters, V (a measure of gray scale variation), and breast cancer (BC) risk. We also examined how C-peptide and BC risk vary across quartiles of mammographic features. Linear and logistic regressions were used to study the associations between C-peptide and MD parameters, and breast cancer. C-peptide was inversely associated with percent MD and positively with non-dense area, but no associations were found with dense area and V measure. C-peptide was associated with an increased risk of invasive BC risk (top vs. bottom quartile, odds ratio = 1.46, 95% CI: 1.12–1.91). No multiplicative interactions were found between C-peptide, MD parameters, and BC risk. Our results suggest a positive association between C-peptide and BC risk, and MD parameters do not seem to modify this association.

Consumption of aspartame and risk of breast cancer in the Nurses' Health Studies.

Debate persists regarding the potential carcinogenicity of aspartame as suggested by experimental studies. Therefore, we prospectively evaluated whether aspartame consumption is associated with breast cancer risk in the Nurses' Health Study (NHS) and Nurses' Health study II (NHSII). We used Cox models to calculate HRs and 95% CIs. During up to 30 years of follow-up with 4-yearly assessments of intake, we documented 10,814 invasive breast cancer cases. Overall, there was no association between aspartame consumption and invasive breast cancer risk (HR per 200 mg/day [approximately one 12 oz serving of diet soda] = 1.00 (95% CI 0.98, 1.03). We observed similar lack of associations after excluding cases occurring in the first 10 years of follow-up (n = 3,125) (HR per 200 mg/day 1.00, 95% CI 0.97, 1.03). In these cohorts, aspartame consumption did not increase breast cancer risk.

Polygenic risk scores stratify breast cancer risk among women with benign breast disease.

Most breast biopsies are diagnosed as benign breast disease (BBD), with 1.5- to fourfold increased breast cancer (BC) risk. Apart from pathologic diagnoses of atypical hyperplasia, few factors aid in BC risk assessment of these patients. We assessed whether a 313-SNP polygenic risk score (PRS) stratifies risk of BBD patients. We pooled data from five Breast Cancer Association Consortium case-control studies (mean age = 59.9 years), including 6,706 cases and 8,488 controls. Using logistic regression, we estimated BC risk associations by self-reported BBD history and strata of PRS, with median PRS category among women without BBD as the referent. We assessed interactions and mediation of BBD and PRS with BC risk. BBD history was associated with increased BC risk (OR = 1.48, 95% CI: 1.37-1.60; p < .001). PRS increased BC risk, irrespective of BBD history (p-interaction = 0.48), with minimal evidence of mediation of either factor by the other. Women with BBD and PRS in the highest tertile had over 2-fold increased odds of BC (OR = 2.73, 95% CI: 2.41-3.09) and those with BBD and PRS in the lowest tertile experienced reduced BC risk (OR = 0.79, 95% CI: 0.70-0.91), compared to the reference group. Women with BBD and PRS in the highest decile had a 3.7- fold increase (95% CI: 3.00-4.61) compared to those with median PRS without BBD. BC risks are elevated among women with BBD and increase progressively with PRS, suggesting that optimal combinations of these factors may improve risk stratification.

Association between human telomerase reverse transcriptase (hTERT) MNS16A polymorphism and risk of breast cancer.

It is well known that telomerase activity is suppressed in normal human tissues and reactivated in tumors, suggesting that the human telomerase reverse transcriptase (hTERT, MIM: 187270) gene may be involved in carcinogenesis. A polymorphic tandem repeat minisatellite located downstream of exon 16 of hTERT and upstream in the putative promoter region of an antisense hTERT transcript, termed MNS16A, results in a functional polymorphism. Because the association between the MNS16A genetic polymorphism and breast cancer (BC) risk remains an open question, the present case-control study was conducted in Shiraz (Fars Province, Southern Iran). A total of 711 samples were collected, including 362 BC patients and 349 healthy individuals. Genotyping was performed by polymerase chain reaction method. Alleles were determined by classifying DNA amplicons of less than and greater than 300bp as short (S) and long (L) alleles, respectively. Different inheritance models (codominant, dominant, recessive, overdominant genotype models and the allele model) were used to evaluate the association between the MNS16A polymorphism and the risk of BC. No significant association was observed in any of the analyses. It should be noted that the statistical power of the comparisons was low. The present study did not support the association between hTERT MNS16A polymorphism and breast cancer risk. Similar studies in other populations with larger sample sizes are needed to determine the association between the hTERT MNS16A polymorphism and susceptibility to breast cancer.

Genetic association and computational analysis of MTHFR gene polymorphisms rs1801131 and rs1801133 with breast cancer in the Bangladeshi population

Methylenetetrahydrofolate reductase (MTHFR) plays a crucial role in regulating one-carbon metabolism. Polymorphisms within the MTHFR gene have been found to increase the risk of breast cancer in different populations. In this study, we evaluated the association of polymorphisms of the MTHFR gene (rs1801133 and rs1801131) with the risk of breast cancer in the Bangladeshi population. This case‒control study included 202 breast cancer patients and 104 healthy controls. After the organic extraction of DNA, genotyping was performed via the PCR-RFLP method. Sanger sequencing was performed to validate the RFLP data. Statistical analyses were performed to evaluate the associations of the polymorphisms. Different computational tools were used to predict the structural and functional consequences of the SNPs. Our study revealed that the MTHFR gene polymorphism rs1801131 is associated with an increased risk of developing breast cancer (p < 0.001, OR = 3.85, 95% CI = 2.06–7.25 for the AC genotype and p < 0.001, OR = 7.82, 95% CI = 2.69–22.05 for the CC genotype). An association was also observed in the dominant model (AC + CC) (p < 0.001, OR = 4.19, 95% CI = 2.28–7.78). For rs1801131, premenopausal status was significantly associated with breast cancer risk (p < 0.001). For rs1801133, no significant association was found with breast cancer risk (p > 0.05, OR = 1.57, 95% CI = 0.90–2.74 for the CT genotype; p > 0.05, OR = 1.35, 95% CI = 0.36–4.92 for the TT genotype). Computational analyses predicted rs1801131 to be tolerated and rs1801133 to be deleterious. Structural analyses demonstrated no significant changes in protein structure but revealed alterations in neighboring interactions according to both bond distances and angles. In conclusion, rs1801131 but not rs1801133 is significantly associated with breast cancer risk in the Bangladeshi population. Moreover, in silico analyses demonstrated changes in the interaction pattern of polymorphic residues with adjacent amino acids.

Impact of graphical display on the intention to undergo risk-reducing salpingo-oophorectomy and mastectomy in individuals positive for BRCA pathogenic variant

The BRCA1/2 pathogenic variant (PV) increases the risk of breast and ovarian cancer; thus, risk-reducing salpingo-oophorectomy (RRSO) and mastectomy (RRM) are recommended. We evaluated the effects of the graphical display of cancer risk compared with those of numerical presentation on the decision-making for risk-reducing (RR) surgery. A total of 471 women representing the Korean population were recruited. The lifetime risk of breast/ovarian cancer were given numerically followed by graphically in hypothetical BRCA1/2 PV-positive cases. Subsequently, the study participants were asked for their willingness to undergo RRSO/RRM. When the ovarian cancer risk was shown as 44.0%, the percentage of study participants who chose RRSO was 41.0% after numerical presentation versus 39.9% after graphical display, of which the difference was not significant. When the breast cancer risk was presented as 72.0%, 30.4% of the participants opted for RRM under numerical presentation, whereas this increased to 38.6% under graphical display, of which the difference was significant (p < 0.0075). The average levels of the cancer risk which study participants consider RR surgery were 57.1% for ovarian cancer and 60.6% for breast cancer. This suggests that the impacts of different formats of risk communication on decision about RRSO or RRM may be different by the absolute levels of ovarian or breast cancer.

Breast Cancer in Users of Levonorgestrel-Releasing Intrauterine Systems

This study uses data from nationwide Danish registries to assesses breast cancer risk with continuous use of levonorgestrel-releasing intrauterine systems, accounting for other hormonal exposures.

Physical activity during adolescence and early adulthood and breast cancer risk before age 40 years.

Breast cancer (BC) incidence is increasing in women under age 40 years, underscoring the need for research on BC risk factors for younger women. We used data from an international family cohort (n=26,348) to examine whether recreational physical activity (RPA) during adolescence and early adulthood are associated with BC risk before age 40. The cohort includes 2,502 women diagnosed with BC before age 40, including 2,408 diagnosed before study enrollment (68% within 5 years of enrollment). Women reported their average hours-per-week of moderate and strenuous RPA during adolescence (12-17 years) and early adulthood (25-34 years), which were converted to total age-adjusted metabolic equivalents-per-week and categorized into quartiles. We conducted attained age analyses until age 40 (follow-up time began at age 18) using Cox proportional hazards regression models adjusted for study center, race and ethnicity, and education. Being in the highest versus lowest quartile of RPA during adolescence and early adulthood were respectively associated with 12% [HR (95% CI): 0.88 (0.78, 0.98)] and 16% [HR (95% CI): 0.84 (0.74, 0.95) lower BC risks before age 40. Being in the highest quartile of RPA during both adolescence and early adulthood (Pearson correlation=0.52) versus neither timepoint was associated with a 22% lower risk [HR (95% CI): 0.78 (0.68, 0.89)]. Findings suggest that RPA during adolescence and early adulthood may lower BC risk before age 40. Policies promoting physical activity during adolescence and early adulthood may be important for reducing the growing burden of breast cancer in younger women.

Double-Edged Sword Effect of Diet and Nutrition on Carcinogenic Molecular Pathways in Breast Cancer.

Environmental exposure to a mixture of chemical xenobiotics acts as a double-edged sword, promoting or suppressing tumorigenesis and the development of breast cancer (BC). Before anything else, we are what we eat. In this review, we highlight both "the good" and "the bad" sides of the daily human diet and dietary patterns that could influence BC risk (BCR) and incidence. Thus, regularly eating new, diversified, colorful, clean, nutrient-rich, energy-boosting, and raw food, increases apoptosis and autophagy, antioxidation, cell cycle arrest, anti-inflammation, and the immune response against BC cells. Moreover, a healthy diet could lead to a reduction in or the inhibition of genomic instability, BC cell stemness, growth, proliferation, invasion, migration, and distant metastasis. We also emphasize that, in addition to beneficial compounds, our food is more and more contaminated by chemicals with harmful effects, which interact with each other and with endogenous proteins and lipids, resulting in synergistic or antagonistic effects. Thus, a healthy and diverse diet, combined with appropriate nutritional behaviors, can exert anti-carcinogenic effects and improve treatment efficacy, BC patient outcomes, and the overall quality of life of BC patients.

Identification of sequence polymorphism in the D-loop region of mitochondrial DNA as a risk factor for breast cancer.

Mitochondrial DNA (mtDNA) variations affect the efficiency of the electron transport chain and production of reactive oxygen species, contributing to carcinogenesis. The D-loop region of mtDNA has emerged as a variation hotspot region in human neoplasia; however, the potential contribution of these variations in breast cancer risk prediction remains unknown. We investigated the relationship between germline single nucleotide polymorphisms (SNPs) in the entire D-loop region and breast cancer risk in Chinese women. Peripheral blood-isolated mtDNA from 2329 patients with breast cancer and 2328 cancer-free controls was examined for SNPs. In the combined cohort, we used traditional risk factors, susceptibility germline polymorphisms, and logistic regression analysis to evaluate the predictive value of susceptibility variants for breast cancer risk. We calculated the area under the receiver operating characteristic curve (AUC) as a measure. We also measured the content of 8-hydroxy-2'-deoxyguanosine (8-OHdG). Individual polymorphisms SNP573 were significantly associated with breast cancer risk in both the discovery and validation cohorts. In the combined cohort, the AUC of the traditional risk factors was 64.3%; after adding susceptibility variants, the AUC was 64.9% (DeLong test, p = 0.007). 8-OHdG levels were significantly higher in patients with breast cancer than in controls and higher in individuals with SNP573 than in those negative for this variation. Overall, oxidative stress might be associated with the risk of breast cancer, and SNP573 might be associated with oxidative stress. Our results indicate the risk potential of polymorphisms in the D-loop region in breast cancer in Southern China.

Validation study of risk-reduction activities after personalized breast cancer education tool in the WISDOM study

Breast cancer risk reduction strategies have been well-validated, but barriers remain for high-risk individuals to adopt them. We performed a study among participants with high risk of breast cancer to validate whether a virtual breast health decision tool impacted a participant’s willingness to start risk-reducing activities, identify barriers to adopting these strategies, and understand if it affects breast cancer anxiety. The study sample was 318 participants in the personalized (investigational) arm of the Women Informed to Screen Depending on Measures of risk (WISDOM) clinical trial. After reviewing the tool, these participants completed a feedback survey. We demonstrated that 15 (4.7%) women were taking endocrine risk reduction, 123 (38.7%) were reducing alcohol intake, and 199 (62.6%) were exercising. In the three-month follow-up survey of 109 respondents, only 8 of 61 (13.1%) women who considered endocrine risk reduction pursued it. In contrast, 11 of 16 (68%) participants who considered alcohol reduction pursued the activity, and 14 of 24 (58%) women who considered exercise followed through. Participants listed fear of side effects as the most common barrier to endocrine risk reduction. We also present further steps to be taken to improve the effectiveness of the Breast Health Decisions tool.

Unrecognised actionability for breast cancer risk variants identified in a national-level review of Australian familial cancer centres.

Breast cancer remains a significant global health challenge. In Australia, the adoption of publicly-funded multigene panel testing for eligible cancer patients has increased accessibility to personalised care, yet has also highlighted the increasing prevalence of variants of uncertain significance (VUS), complicating clinical decision-making. This project aimed to explore the spectrum and actionability of breast cancer VUS in Australian familial cancer centers (FCCs). Leveraging data from 11 FCCs participating in the Inherited Cancer Connect database, we retrieved VUS results from 1472 patients. Through ClinVar crosschecks and application of gene-specific ACMG/AMP guidelines, we showed the potential for reclassification of 4% of unique VUS as pathogenic or likely pathogenic, and 80% as benign or likely benign. Surveys conducted with FCCs and diagnostic laboratories described current practices and challenges in variant reclassifications, highlighting resource constraints preventing periodic VUS review and notifications from the laboratories to the FCCs. Our study suggests there are benefits to routine VUS review and reclassification, particularly in publicly-funded healthcare systems. Future research should focus on assessing the clinical impact and cost-effectiveness of implementing routine variant review practices, alongside efforts to enhance communication between FCCs and laboratories.

Personal history of irradiation and risk of breast cancer: A Mendelian randomisation study.

Studies on the relationship between personal history of irradiation and breast cancer have been reported for a long time. Still, epidemiological studies have not been conclusive, and the causal relationship is unclear. To address this issue, we employed Mendelian randomisation (MR) analysis to examine the association between individual radiation exposure history and breast cancer. We used a series of quality control methods to select single nucleotide polymorphism (SNP) closely related to exposure. Meanwhile, several analysis methods were used to analyse the sample data to make the conclusion more reliable. To evaluate the horizontal pleiotropy, heterogeneity and stability of SNPs for breast cancer, the MR-Egger intercept test, Cochran's Q test and 'leave one' sensitivity analysis were used. Finally, the outlier variation determined by the Mendelian Randomisation Pleiotropy RESidual Sum and Outlier test is gradually eliminated to reduce the influence of heterogeneity and horizontal pleiotropy. After implementing rigorous quality control procedures, we carefully chose 102 qualified instrumental variables closely associated with the selected exposure for sensitivity analysis. This was conducted to evaluate the heterogeneity, level multiplicity, and stability of SNPs in the context of personal radiation history and its correlation with breast cancer. The results of the inverse variance weighted method analysis revealed a positive correlation between personal radiation and a heightened risk of breast cancer (odds ratio (OR) = 1.52; 95% confidence interval (CI) = 1.30-1.77). We also validated on another data set; the results were similar (OR = 1.51; 95% CI = 1.27-1.81). Furthermore, the findings from the sensitivity analysis were consistent. At the genetic level, our research demonstrated that personal radiation exposure is associated with an elevated risk of breast cancer. Using genetic data provides evidence and strengthens the causal link that personal radiation causes breast cancer.

Age to Initiate Routine Breast Cancer Screening.

This Clinical Practice Update provides revised guidance on the age to start routine breast cancer screening with mammography. This document is a focused update of related content in Practice Bulletin No. 179, Breast Cancer Risk Assessment and Screening in Average-Risk Women (Obstet Gynecol 2017;130:e1-16).

Active symptom monitoring for premenopausal women with breast cancer initiating adjuvant endocrine therapy: Protocol for the SWOG S2010 randomized controlled efficacy trial

BackgroundPremenopausal women with early stage, high risk hormone receptor positive breast cancer are at risk of early discontinuation of adjuvant endocrine therapy (ET), primarily because of toxicity, which can increase the risk of disease recurrence and death. We hypothesize that identification of bothersome symptoms between clinic visits, and automated notification of clinicians about symptoms, will result in improved persistence with ET. MethodsPre- and perimenopausal women planning to receive adjuvant treatment with tamoxifen or an aromatase inhibitor plus ovarian function suppression or ablation for treatment of breast cancer are eligible. A total of 540 participants will be enrolled and randomized 1:1 to patient education with or without Active Symptom Monitoring (ASM). The ASM intervention includes 6 symptom questions (hot flashes, sadness, anxiety, insomnia, vaginal dryness, joint pain) that will be completed via text, email, or telephone weekly for 24 weeks, then every 4 weeks for 48 weeks. All participants will complete a battery of questionnaires every 12 weeks to examine symptoms, beliefs about medicine, self-efficacy, and ET adherence. Optional blood draws will be collected at baseline and after 12, 48, and 72 weeks of therapy to examine estradiol and ET concentrations. The primary endpoint is time to nonpersistence with initially prescribed ET within the first 72 weeks, evaluated using Kaplan-Meier plots and multivariable Cox regression. ConclusionWe expect early identification and management of ET-related toxicities to improve persistence with breast cancer therapy, breast cancer outcomes, and quality of life for premenopausal women at high risk of breast cancer recurrence.Clinicaltrials.govNCT05568472

Gail Model for Assessing the Risk of Breast Cancer in Women with Fibroadenoma: A Diagnostic Accuracy Study

Gail Model for Assessing the Risk of Breast Cancer in Women with Fibroadenoma: A Diagnostic Accuracy Study