Established breast cancer risk factors and risk of intrinsic tumor subtypes

The association between infectious agents and breast cancer: a review of the epidemiologic evidence

PURPOSE

Several viruses have been casually linked to human cancers, including cervical, nasopharyngeal, liver, sarcoma, and Merkel cell carcinomas. However, the etiologic contribution of viral infections to breast cancer, the number one incident cancer among women worldwide, is not well established. Among studies exploring associations of viruses with breast cancer, potential linkages have been identified between breast cancer and five viruses: beta retrovirus, (i.e., mouse mammary tumor virus), human papillomavirus, Epstein Barr virus. bovine leukemia virus, and human cytomegalovirus.

METHODS

In this review, we provide a comprehensive evaluation of epidemiological ecologic, case-control, case-only, and cohort studies investigating these associations. We discuss results from several existing reviews and meta-analyses, evaluate epidemiological studies published in the past five years, and assess the relationship between these viruses and breast tumor clinicopathological factors.

RESULTS

The strongest epidemiological evidence for a viral role in breast cancer exists for MMTV and HPV, though limitations include lack of prospective studies for MMTV and potential detection bias in HPV studies. Viral detection challenges have limited studies of EBV and HCMV. Fewer studies have evaluated BLV, and though it has been associated with higher risk of breast cancer, sample sizes are quite small.   CONCLUSION: While epidemiologic evidence exists for an association between these five viruses and breast cancer, various methodological issues and lack of prospective studies preclude robust conclusions. Future research should prioritize establishing a temporal relationship between infection and disease, minimizing misclassification of detection assays, and further exploring the influence of co-infections.

Risk perception regarding social determinants of health among women with breast cancer in Iran: a qualitative study

OBJECTIVES

Breast cancer is the most common cancer among women all around the world. Today, in addition to factors including hormones and genetics that are involved in the occurrence of breast cancer, special attention is paid to the role of social and non-medical determinants of health. This study aims to explore the perception of Social Determinants of Health (SDH) in women with breast cancer.

DESIGN

Qualitative study design with a conventional thematic analysis approach.

SETTING

The study was conducted in Tehran, Iran, between December 2021 and February 2023.

PARTICIPANTS

19 women with breast cancer were selected through purposeful and snowball sampling with maximum variation. Sampling continued until data saturation was reached.

PRIMARY AND SECONDARY OUTCOME MEASURES

The study categorised the extracted codes from interviews into three main categories and 12 subcategories related to SDH in women with breast cancer.

RESULTS

The study identified factors such as personal and family health records, health behaviours and lifestyles and medical screening and follow-up as key themes in the perception of SDH among women with breast cancer. The main categories were also categorised into 12 subcategories, 'including family history', 'environmental factors', 'hormonal and medicinal changes', 'metaphysical factors', 'traditional medicine-related factors', 'stress', 'body weight', 'physical activity', 'nutrition', 'smoking and tobacco use', 'screening', 'self-examination' and 'barriers to medical follow-up'. 'Near the telecommunications tower', 'Improper use of supplements', 'Being subjected to the evil eye regularly', 'Eating cold nature foods', 'Breast weight' and 'Being ashamed of the doctor' were some examples of the codes.

CONCLUSIONS

Participants identified a number of environmental, personal and cultural factors as contributing to the disease. Woman's screening behaviours were influenced by factors such as fear of disease and death, disbelief in getting sick and shame, depending on cultural context. The study suggests the need for further research to explore the impact of these factors on screening behaviours and outcomes in different cultural contexts.

Educational level and characteristics of invasive breast cancer: findings from a French prospective cohort

PURPOSE

Breast cancer (BC) characteristics are known to influence patients survival. Social differences have been reported by previous studies for those characteristics but questions persist because of inconsistent conclusions. We aimed to investigate the impact of education on BC stage, grade, and hormone receptor (HR) status, while adjusting for potential confounders including a broad set of health behaviors, anthropometric measures, and reproductive factors.

METHODS

In the French E3N cohort, 5236 women developed a primary invasive BC for which there was available information on stage, grade, and HR status. No multivariate analyses was performed for BC stage based on the lack of association in bivariate analyses. Odds ratios and confidence intervals were estimated using multinomial logistic regression models for BC grade or binomial logistic regression models for HR status of BC.

RESULTS

Women with a lower education were diagnosed with higher grade BC compared to women with a higher education (1.32 [1.12; 1.57]). This association was slightly attenuated after adjustment for covariates independently and more strongly affected in the fully adjusted model (1.20 [0.99; 1.45]). A significant association was observed between lower education and HR- status of BC (1.20 [1.02; 1.42]) attenuated after adjustment for age at first childbirth (1.12 [0.95; 1.33]).

CONCLUSION

In this cohort, education was associated with BC grade and HR status but not stage at diagnosis. The link between education and BC grade was not entirely explained by the different adjustments. A specific mechanism could be at play and deserves further investigations.

Cancer detection rate of breast-MR in supplemental screening after negative mammography in women with dense breasts. Preliminary results of the MA-DETECT-Study after 200 participants

BACKGROUND

Due to increased cancer detection rates (CDR), breast MR (breast MRI) can reduce underdiagnosis of breast cancer compared to conventional imaging techniques, particularly in women with dense breasts. The purpose of this study is to report the additional breast cancer yield by breast MRI in women with dense breasts after receiving a negative screening mammogram.

METHODS

For this study we invited consecutive participants of the national German breast cancer Screening program with breast density categories ACR C & D and a negative mammogram to undergo additional screening by breast MRI. Endpoints were CDR and recall rates. This study reports interim results in the first 200 patients. At a power of 80% and considering an alpha error of 5%, this preliminary population size is sufficient to demonstrate a 4/1000 improvement in CDR.

RESULTS

In 200 screening participants, 8 women (40/1000, 17.4-77.3/1000) were recalled due to positive breast MRI findings. Image-guided biopsy revealed 5 cancers in 4 patients (one bilateral), comprising four invasive cancers and one case of DCIS. 3 patients revealed 4 invasive cancers presenting with ACR C breast density and one patient non-calcifying DCIS in a woman with ACR D breast density, resulting in a CDR of 20/1000 (95%-CI 5.5-50.4/1000) and a PPV of 50% (95%-CI 15.7-84.3%).

CONCLUSION

Our initial results demonstrate that supplemental screening using breast MRI in women with heterogeneously dense and very dense breasts yields an additional cancer detection rate in line with a prior randomized trial on breast MRI screening of women with extremely dense breasts. These findings are highly important as the population investigated constitutes a much higher proportion of women and yielded cancers particularly in women with heterogeneously dense breasts.

Multi-tissue transcriptome-wide association studies identified 235 genes for intrinsic subtypes of breast cancer

BACKGROUND

Although genome-wide association studies (GWAS) of breast cancer (BC) identified common variants which differ between intrinsic subtypes, genes through which these variants act to impact BC risk have not been fully established. Transcriptome-wide association studies (TWAS) have identified genes associated with overall BC risk, but subtype-specific differences are largely unknown.

METHODS

We performed two multi-tissue TWAS for each BC intrinsic subtype, including an expression-based approach that collated TWAS signals from expression quantitative trait loci (eQTLs) across multiple tissues and a novel splicing-based approach that collated signals from splicing QTLs (sQTLs) across intron clusters and subsequently across tissues. We used summary statistics for five intrinsic subtypes including Luminal A-like, Luminal B-like, Luminal B/HER2-negative-like, HER2-enriched-like, and triple-negative BC, generated from 106 278 BC cases and 91 477 controls in the Breast Cancer Association Consortium.

RESULTS

Overall, we identified 235 genes in 88 loci that were associated with at least one of the five intrinsic subtypes. Most genes were subtype-specific, and many have not been reported in previous TWAS. We discovered common variants that modulate expression of CHEK2 confer increased risk to Luminal A-like BC, in contrast to the viewpoint that CHEK2 primarily harbors rare, penetrant mutations. Additionally, our splicing-based TWAS provided population-level support for MDM4 splice variants that increased the risk of triple-negative BC.

CONCLUSION

Our comprehensive, multi-tissue TWAS corroborated previous GWAS loci for overall BC risk and intrinsic subtypes, while underscoring how common variation that impacts expression and splicing of genes in multiple tissue types can be used to further elucidate the etiology of BC.

Convergence between helminths and breast cancer: intratumoral injection of the excretory/secretory antigens of the human parasite Toxocara canis (EST) increase lung macro and micro metastasis

Introduction

Worldwide, breast cancer is the most important cancer in incidence and prevalence in women. Different risk factors interact to increase the probability of developing it. Biological agents such as helminth parasites, particularly their excretory/secretory antigens, may play a significant role in tumor development. Helminths and their antigens have been recognized as inducers or promoters of cancer due to their ability to regulate the host's immune response. Previously in our laboratory, we demonstrated that chronic infection by Toxocara canis increases the size of mammary tumors, affecting the systemic response to the parasite. However, the parasite does not invade the tumor, and we decided to study if the excretion/secretion of antigens from Toxocara canis (EST) can affect the progression of mammary tumors or the pathophysiology of cancer which is metastasis. Thus, this study aimed to determine whether excretion/secretion T. canis antigens, injected directly into the tumor, affect tumor growth and metastasis.

Methods

We evaluated these parameters through the monitoring of the intra-tumoral immune response.

Results

Mice injected intratumorally with EST did not show changes in the size and weight of the tumors; although the tumors showed an increased microvasculature, they did develop increased micro and macro-metastasis in the lung. The analysis of the immune tumor microenvironment revealed that EST antigens did not modulate the proportion of immune cells in the tumor, spleen, or peripheral lymph nodes. Macroscopic and microscopic analyses of the lungs showed increased metastasis in the EST-treated animals compared to controls, accompanied by an increase in VEGF systemic levels.

Discussion

Thus, these findings showed that intra-tumoral injection of T. canis EST antigens promote lung metastasis through modulation of the tumor immune microenvironment.

Risk factors for breast cancer subtypes by race and ethnicity: A scoping review of the literature

Background

Breast cancer is comprised of distinct molecular subtypes. Studies have reported differences in risk factor associations with breast cancer subtypes, especially by tumor estrogen receptor (ER) status, but their consistency across racial and ethnic populations has not been comprehensively evaluated.

Methods

We conducted a qualitative, scoping literature review using the Preferred Reporting Items for Systematic Reviews and Meta-analysis, extension for Scoping Reviews to investigate consistencies in associations between 18 breast cancer risk factors (reproductive, anthropometric, lifestyle, and medical history) and risk of ER-defined subtypes in women who self-identify as Asian, Black or African American, Hispanic or Latina, or White. We reviewed publications between January 1, 1990 and July 1, 2022. Etiologic heterogeneity evidence (convincing, suggestive, none, or inconclusive) was determined by expert consensus.

Results

Publications per risk factor ranged from 14 (benign breast disease history) to 66 (parity). Publications were most abundant for White women, followed by Asian, Black or African American, and Hispanic or Latina women. Etiologic heterogeneity evidence was strongest for parity, followed by age at first birth, post-menopausal BMI, oral contraceptive use, and estrogen-only and combined menopausal hormone therapy. Evidence was limited for other risk factors. Findings were consistent across racial and ethnic groups, although the strength of evidence varied.

Conclusion

The literature supports etiologic heterogeneity by ER for some established risk factors that are consistent across race and ethnicity groups. However, in non-White populations evidence is limited. Larger, more comparable data in diverse populations is needed to better characterize breast cancer etiologic heterogeneity.

Evaluation of Contrast-Enhanced Mammography and Development of Flowchart for BI-RADS Classification of Breast Lesions

This study aimed to evaluate contrast-enhanced mammography (CEM) and to compare breast lesions on CEM and breast magnetic resonance imaging (MRI) using 5 features. We propose a flowchart for BI-RADS classification of breast lesions on CEM based on the Kaiser score (KS) flowchart for breast MRI. Sixty-eight subjects (women and men; median age 61.4 ± 11.6 years) who were suspected of having a malignant process in the breast based on digital mammography (MG) findings were included in the study. The patients underwent breast ultrasound (US), CEM, MRI and biopsy of the suspicious lesion. There were 47 patients with malignant lesions confirmed by biopsy and 21 patients with benign lesions, for each of which a KS was calculated. In the patients with malignant lesions, the MRI-derived KS was 9 (IQR 8-9); its CEM equivalent was 9 (IQR 8-9); and BI-RADS was 5 (IQR 4-5). In patients with benign lesions, MRI-derived KS was 3 (IQR 2-3); its CEM equivalent was 3 (IQR 1.7-5); and BI-RADS was 3 (IQR 0-4). There was no significant difference between the ROC-AUC of CEM and MRI (p = 0.749). In conclusion, there were no significant differences in KS results between CEM and breast MRI. The KS flowchart is useful for evaluating breast lesions on CEM.

A generalized non-linear model predicting efficacy of neoadjuvant therapy in HER2+ breast cancer

Neoadjuvant therapy (NAT) is currently recommended to patients with human epidermal growth factor receptor 2-positive breast cancer (HER2+ BC) that typically exhibit a poor prognosis. The tumor immune microenvironment profoundly affects the efficacy of NAT. However, the correlation between tumor-infiltrating lymphocytes or their specific subpopulations and the response to NAT in HER2+ BC remains largely unknown. In our study, the immune infiltration status of 295 patients was classified as "immune-rich" or "immune-poor" phenotypes. The "immune-rich" phenotype was significantly positively related to pathological complete response (pCR). Ten genes were correlated with both pCR and the immune phenotype based on the results of spline and logistic regression. We constructed a generalized non-linear model combining linear and non-linear gene effects and successfully validated its predictive power using an internal and external validation set (AUC = 0.819, 0.797; respectively) and a clinical set (accuracy = 0.75).

Role of Secreted Frizzled-Related Protein 1 in Early Breast Carcinogenesis and Breast Cancer Aggressiveness

A human transcriptome array on ERα-positive breast cancer continuum of risk identified Secreted Frizzled-Related Protein 1 (SFRP1) as decreased during breast cancer progression. In addition, SFRP1 was inversely associated with breast tissue age-related lobular involution, and differentially regulated in women with regard to their parity status and the presence of microcalcifications. The causal role of SFRP1 in breast carcinogenesis remains, nevertheless, not well understood. In this study, we characterized mammary epithelial cells from both nulliparous and multiparous mice in organoid culture ex vivo, in the presence of estradiol (E2) and/or hydroxyapatite microcalcifications (HA). Furthermore, we have modulated SFRP1 expression in breast cancer cell lines, including the MCF10A series, and investigated their tumoral properties. We observed that organoids obtained from multiparous mice were resistant to E2 treatment, while organoids obtained from nulliparous mice developed the luminal phenotype associated with a lower ratio between Sfrp1 and Esr1 expression. The decrease in SFRP1 expression in MCF10A and MCF10AT1 cell lines increased their tumorigenic properties in vitro. On the other hand, the overexpression of SFRP1 in MCF10DCIS, MCF10CA1a, and MCF7 reduced their aggressiveness. Our results support the hypothesis that a lack of SFRP1 could have a causal role in early breast carcinogenesis.

Breast cancer subtype and clinical characteristics in women from Peru

Introduction

Breast cancer is a heterogeneous disease, and the distribution of the different subtypes varies by race/ethnic category in the United States and by country. Established breast cancer-associated factors impact subtype-specific risk; however, these included limited or no representation of Latin American diversity. To address this gap in knowledge, we report a description of demographic, reproductive, and lifestyle breast cancer-associated factors by age at diagnosis and disease subtype for The Peruvian Genetics and Genomics of Breast Cancer (PEGEN-BC) study.

Methods

The PEGEN-BC study is a hospital-based breast cancer cohort that includes 1943 patients diagnosed at the Instituto Nacional de Enfermedades Neoplásicas in Lima, Peru. Demographic and reproductive information, as well as lifestyle exposures, were collected with a questionnaire. Clinical data, including tumor Hormone Receptor (HR) status and Human Epidermal Growth Factor Receptor 2 (HER2) status, were abstracted from electronic medical records. Differences in proportions and mean values were tested using Chi-squared and one-way ANOVA tests, respectively. Multinomial logistic regression models were used for multivariate association analyses.

Results

The distribution of subtypes was 52% HR+HER2-, 19% HR+HER2+, 16% HR-HER2-, and 13% HR-HER2+. Indigenous American (IA) genetic ancestry was higher, and height was lower among individuals with the HR-HER2+ subtype (80% IA vs. 76% overall, p=0.007; 152 cm vs. 153 cm overall, p=0.032, respectively). In multivariate models, IA ancestry was associated with HR-HER2+ subtype (OR=1.38,95%CI=1.06-1.79, p=0.017) and parous women showed increased risk for HR-HER2+ (OR=2.7,95%CI=1.5-4.8, p<0.001) and HR-HER2- tumors (OR=2.4,95%CI=1.5-4.0, p<0.001) compared to nulliparous women. Multiple patient and tumor characteristics differed by age at diagnosis (<50 vs. >=50), including ancestry, region of residence, family history, height, BMI, breastfeeding, parity, and stage at diagnosis (p<0.02 for all variables).

Discussion

The characteristics of the PEGEN-BC study participants do not suggest heterogeneity by tumor subtype except for IA genetic ancestry proportion, which has been previously reported. Differences by age at diagnosis were apparent and concordant with what is known about pre- and post-menopausal-specific disease risk factors. Additional studies in Peru should be developed to further understand the main contributors to the specific age of onset and molecular disease subtypes in this population and develop population-appropriate predictive models for prevention.

Prediction of Breast Self-Examination Behavior Among Omani Undergraduate Students Using Champion's Health Belief Model

Introduction

Breast cancer (BC) is a most common and frequently occurring malignancy of women worldwide. Breast self-examination (BSE) is important for the early detection and prevention of BC and to limit the morbidity and mortality. Young students are ideal people to understand and motivate other women to perform BSE.

Objective

BSE behavior of undergraduate students was predicted using Champion's Health Belief Model Scale (CHBMS).

Methods

A descriptive cross-sectional design was adopted. This study was conducted in all nine colleges of Sultan Qaboos University, , Oman. Three-hundred eighty-one female undergraduate students were selected through convenient sampling technique. The health belief towards BSE was predicted using CHBMS.

Results

The mean and SD of beliefs about the benefits of performing BSE showed 10.84 and 3.2, respectively. Mean and SD of confidence in performing BSE indicated 56.24 and 10.8. Likewise, the mean and SD of barriers in performing BSE are 13.58 and 4.2. Source of information is found to be a statistically significant predictor of barrier in performing BSE at p < .05.

Conclusion

If the self- confidence of women in performing BSE improves, the women will uptake BSE more frequently thereby they can be prevented from developing the adverse consequences of advanced stages of breast cancer.

The Role of miRNAs in the Prognosis of Triple-Negative Breast Cancer: A Systematic Review and Meta-Analysis

Breast cancer is one of the most common malignancies among women around the world. The basal or triple-negative subtype (TNBC) is a heterogeneous group of tumors, characterized by its aggressive and metastatic nature, with low survival and worse prognosis. Research on genetic biomarkers, such as microRNAs (miRs) in TNBC, demonstrate their relevance in the prognosis of the disease. Therefore, the objective of this research was to verify the role of miRs in the prognosis of TNBC. A search was carried out in the PubMed (MEDLINE), Web of Science, and Scopus databases, with articles in the English language from 2010 to 2022. Only articles that analyzed the role of miRNAs in the prognosis of TNBC and that met the criteria of the MOOSE method were included. For the preparation and planning of this systematic review, a PRISMA checklist and the MOOSE method were used. The Newcastle-Ottawa Scale was used to analyze the quality of the included studies. The excluded criteria considered were: (1) studies that presented duplication in the databases; (2) reviews of the literature, clinical case reports, meta-analyses, conference abstracts, letters to the editor, theses, dissertations, and book chapters; (3) studies that stratified only women diagnosed with other subtypes of breast cancer subtypes; (4) experiments without a control or comparison group. After the bibliographic survey of the 2.274 articles found, 43 articles met the inclusion criteria, totaling 5421 patients with TNBC analyzed for this review. Six miRs (miR-155, miR-21, miR-27a/b/, miR-374a/b, miR-30a/c/e, and miR-301a) were included in the meta-analysis. A low expression of miR-155 was associated with reduced overall survival (OS) (HR: 0.68, 95% CI: 0.58-0.81). A high expression of miR-21 was a predictor of OS reduction (HR: 2.56; 95% CI: 1.49-4.40). In addition, high levels of miR-27a/b and miR-301a/b were associated with lower OS, while the decreased expression levels of miR-30 and miR-374a/b were associated with worse relapse-free survival (RFS) and shorter disease-free survival (DFS), respectively. The present study revealed that miRs play essential roles in the development of metastases, in addition to acting as suppressors of the disease, thus improving the prognosis of TNBC. However, the clinical application of these findings has not yet been investigated.

Insulinemic potential of diet and risk of total and subtypes of breast cancer among US females

BACKGROUND

Insulin resistance and hyperinsulinemia play important roles in the progression of multiple chronic disease and conditions. Diet modulates insulin response; however, evidence is limited regarding whether diets with higher insulinemic potential increase the risk of invasive breast cancer.

OBJECTIVES

We aimed to prospectively evaluate the association between a food-based empirical dietary index for hyperinsulinemia (EDIH) and the incidence of invasive breast cancer.

METHODS

We prospectively followed 76,686 women from the Nurses' Health Study (NHS; 1984-2016) and 93,287 women from the Nurses' Health Study II (NHSII; 1991-2017). Diet was assessed by food-frequency questionnaires every 4 y. The insulinemic potential of diet was evaluated using the previously established EDIH based on circulating C-peptide concentrations. Higher scores indicate higher insulinemic potential of the diet. Covariates included reproductive, hormonal, and anthropometric factors (height and BMI at age 18 y); race; socioeconomic status; total alcohol intake; total caloric intake; and physical activity.

RESULTS

During 4,216,106 person-years of follow-up, we documented 10,602 breast cancer cases (6689 NHS, 3913 NHSII). In the pooled multivariable-adjusted analyses, women in the highest, compared with the lowest, EDIH quintile (Q) were at higher breast cancer risk (HRQ5 vs. Q1 = 1.15; 95% CI: 1.07, 1.24; P-trend < 0.01). Although heterogeneity by estrogen receptor (ER) status was nonsignificant, the strongest association between EDIH and breast cancer was observed for ER-negative tumors (HRQ5 vs. Q1 = 1.21; 95% CI: 1.00, 1.46; P-trend = 0.02). Among tumor molecular subtypes, the strongest associations were observed for human epidermal growth factor receptor 2 (HER2)-enriched tumors (HRQ5 vs. Q1 = 1.62; 95% CI: 1.01, 2.61; P-trend = 0.02).

CONCLUSIONS

A dietary pattern contributing to hyperinsulinemia and insulin resistance was associated with greater breast cancer risk, especially ER-negative and HER2-enriched tumors. Our findings suggest that dietary modifications to reduce insulinemic potential may reduce the risk of breast cancer.

Racial and regional disparities of triple negative breast cancer incidence rates in the United States: An analysis of 2011-2019 NPCR and SEER incidence data

Objective

Triple negative breast cancer (TNBC) is a more aggressive subtype resistant to conventional treatments with a poorer prognosis. This study was to update the status of TNBC and the temporal changes of its incidence rate in the US.

Methods

Women diagnosed with breast cancer during 2011-2019 were obtained from the National Program of Cancer Registries (NPCR) and Surveillance, Epidemiology and End Results (SEER) Program SEER^*Stat Database which covers the entire population of the US. The TNBC incidence and its temporal trends by race, age, region (state) and disease stage were determined during the period.

Results

A total of 238,848 (or 8.8%) TNBC women were diagnosed during the study period. TNBC occurred disproportionally higher in women of Non-Hispanic Black, younger ages, with cancer at a distant stage or poorly/undifferentiated. The age adjusted incidence rate (AAIR) for TNBC in all races decreased from 14.8 per 100,000 in 2011 to 14.0 in 2019 (annual percentage change (APC) = -0.6, P = 0.024). Incidence rates of TNBC significantly decreased with APCs of -0.8 in Non-Hispanic White women, -1.3 in West and -0.7 in Northeastern regions. Women with TNBC at the age of 35-49, 50-59, and 60-69 years, and the disease at the regional stage displayed significantly decreased trends. Among state levels, Mississippi (20.6) and Louisiana (18.9) had the highest, while Utah (9.1) and Montana (9.6) had the lowest AAIRs in 2019. New Hampshire and Indiana had significant and highest decreases, while Louisiana and Arkansas had significant and largest increases in AAIR. In individual races, TNBC displayed disparities in temporal trends among age groups, regions and disease stages. Surprisingly, Non-Hispanic White and Hispanic TNBC women (0-34 years), and Non-Hispanic Black women (≥70 years) during the entire period, as well as Asian or Pacific Islander women in the South region had increased trends between 2011 and 2017.

Conclusion

Our study demonstrates an overall decreased trend of TNBC incidence in the past decade. Its incidence displayed disparities among races, age groups, regions and disease stages. Special attention is needed for a heavy burden in Non-Hispanic Black and increased trends in certain groups.

Oral Contraceptive Use and Assessment of Breast Cancer Risk among Premenopausal Women via Molecular Characteristics: Systematic Review with Meta-Analysis

Breast cancer is divided into four molecular subtypes. Each one has distinct clinical features. The aim of this study was to assess individual breast cancer subtype risk in premenopausal women taking oral contraceptives (OCs). Databases (MEDLINE; PubMed, EMBASE, and the Cochrane Library) were searched to January 2022 to identify case-control studies meeting the inclusion criteria. The influence of OCs intake on the risk of ER-positive breast cancer (ER+BC) was revealed to be non-significant with regard to reduction: OR = 0.9134, 95% CI: 0.8128 to 1.0265, p = 0.128. Assessment of ER-negative subtype breast cancer (ER-BC) risk indicated that OCs use significantly increased the risk: OR = 1.3079, 95% CI: 1.0003 to 1.7100, p = 0.050. Analysis for HER2-positive breast cancer (HER2+BC) risk showed that OCs use statistically non-significantly lowered the risk: OR = 0.8810, 95% CI: 0.5977 to 1.2984, p = 0.522. Meta-analysis with regard to Triplet-negative breast cancer (TNBC) risk showed non-statistically significant increased risk: OR = 1.553, 95% CI: 0.99 to 2.43, p = 0.055. The findings of the meta-analysis suggest that breast cancer risk in premenopausal women may vary with respect to molecular subtypes. Extensive scientific work is still necessary in order to understand the impact of OCs use on breast cancer risk in young women.

Lifetime personal cigarette smoking and risk of young-onset breast cancer by subtype among non-Hispanic Black and White women in the Young Women's Health History Study

PURPOSE

To evaluate the association between lifetime personal cigarette smoking and young-onset breast cancer (YOBC; diagnosed <50 years of age) risk overall and by breast cancer (BC) subtype, and whether risk varies by race or socioeconomic position (SEP).

METHODS

Data are from the Young Women's Health History Study (YWHHS), a population-based case-control study of non-Hispanic Black (NHB) and White (NHW) women, ages 20-49 years (n = 1812 cases, n = 1381 controls) in the Los Angeles County and Metropolitan Detroit Surveillance, Epidemiology, and End Results (SEER) registry areas, 2010-2015. Lifetime personal cigarette smoking characteristics and YOBC risk by subtype were examined using sample-weighted, multivariable-adjusted polytomous logistic regression.

RESULTS

YOBC risk associated with ever versus never smoking differed by subtype (Pheterogeneity = 0.01) with risk significantly increased for Luminal A (adjusted odds ratio [aOR] 1.34; 95% confidence interval [CI] 1.06-1.68) and HER2-type (aOR 1.97; 95% CI 1.23-3.16), and no association with Luminal B or Triple Negative subtypes. Additionally, ≥30 years since smoking initiation (versus never) was statistically significantly associated with an increased risk of Luminal A (aOR 1.55; 95% CI 1.07-2.26) and HER2-type YOBC (aOR 2.77; 95% CI 1.32-5.79), but not other subtypes. In addition, among parous women, smoking initiated before first full-term pregnancy (versus never) was significantly associated with an increased risk of Luminal A YOBC (aOR 1.45; 95% CI 1.11-1.89). We observed little evidence for interactions by race and SEP.

CONCLUSION

Findings confirm prior reports of a positive association between cigarette smoking and Luminal A YOBC and identify a novel association between smoking and HER2-type YOBC.

Establishment of a new cell line of canine inflammatory mammary cancer: IMC-118

Canine inflammatory mammary cancer (IMC) has long been regarded as an attractive animal model for research into human inflammatory breast cancer (IBC), Although some canine mammary tumour cell lines corresponding to human mammary cancer cell lines have been established, there is still a need to supplement the canine mammary tumour cell bank. The goal of this study was to create a new type of IMC cell line. The primary tumour, IMC-118, was identified as IMC by pathology examination. Immunohistochemistry analysis revealed negative immunoreactivity to oestrogen receptor (ER), but positive immunoreactivity to progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER-2). Immunofluorescence (IF) analysis revealed that the IMC-118 cell line from this primary tumour was negative for ER but positive for PR and HER-2, and was also positive for epithelial and mesenchymal cell markers. This cell line was cultured stably for more than 50 passages and grew well after cryopreservation. In vivo, tumour masses and metastases in the lungs were discovered after inoculating the IMC-118 cells into the nude mice model. As a result, a novel canine IMC cell line, IMC-118, was effectively established, and could be employed as a promising model for immunotherapy and epithelial-mesenchymal transition mechanism of IMC research in both dogs and humans.

AI in Breast Cancer Imaging: A Survey of Different Applications

Breast cancer was the most diagnosed cancer in 2020. Several thousand women continue to die from this disease. A better and earlier diagnosis may be of great importance to improving prognosis, and that is where Artificial Intelligence (AI) could play a major role. This paper surveys different applications of AI in Breast Imaging. First, traditional Machine Learning and Deep Learning methods that can detect the presence of a lesion and classify it into benign/malignant-which could be important to diminish reading time and improve accuracy-are analyzed. Following that, researches in the field of breast cancer risk prediction using mammograms-which may be able to allow screening programs customization both on periodicity and modality-are reviewed. The subsequent section analyzes different applications of augmentation techniques that allow to surpass the lack of labeled data. Finally, still concerning the absence of big datasets with labeled data, the last section studies Self-Supervised learning, where AI models are able to learn a representation of the input by themselves. This review gives a general view of what AI can give in the field of Breast Imaging, discussing not only its potential but also the challenges that still have to be overcome.

Association between the rs4784227-CASC16 polymorphism and the risk of breast cancer: A meta-analysis

OBJECTIVE

Although several studies have identified an association between the rs4784227-cancer susceptibility candidate gene 16 (CASC16) polymorphism and breast cancer, the results remain inconclusive. Therefore, we conducted a meta-analysis to assess the relationship between the rs4784227-CASC16 polymorphism and breast cancer risk.

METHODS

Studies were searched in the PubMed, Web of Science, Embase, Google Scholar, and Cochran Library databases until June 10, 2021, to identify all potential literature on rs4784227-CASC16 polymorphism and breast cancer risk association. Fixed-effect or random-effect models were used to calculate odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs). Subgroup analyses, publication bias, and sensitivity analyses were also conducted.

RESULTS

Seventeen eligible studies involving 34,719 subjects (18,445 cases and 16,274 healthy controls) from 7 articles were included in the current meta-analysis. The pooled ORs regarding the association between the rs4784227-CASC16 polymorphism and breast cancer risk were statistically significant [T vs C: OR = 1.244, 95% CI = 1.202-1.287; TT vs CT + CC: OR = 1.407, 95% CI = 1.296-1.528; CC vs CT + TT: OR = 0.777, 95% CI = 0.745-0.811; TT vs CC: OR = 1.544, 95% CI = 1.419-1.681; CT vs CC: OR = 1.244, 95% CI = 1.189-1.301]. On subgroup analysis, the rs4784227-CASC16 T/C gene has a certain correlation with breast cancer susceptibility in Asian and North American populations, but no significant risk in the Australian population.

CONCLUSION

Our pooled analysis showed a significant association between the rs4784227- (T) allele and breast cancer susceptibility in Asian and North American populations, and intervention with this mutation might be a new therapeutic strategy for breast cancer. However, large-scale and well-designed studies are needed in different populations to further evaluate the role of the rs4784227-CASC16 polymorphism in breast cancer.

The effect of obesity on adipose-derived stromal cells and adipose tissue and their impact on cancer

The significant increase in the incidence of obesity represents the next global health crisis. As a result, scientific research has focused on gaining deeper insights into obesity and adipose tissue biology. As a result of the excessive accumulation of adipose tissue, obesity results from hyperplasia and hypertrophy within the adipose tissue. The functional alterations in the adipose tissue are a confounding contributing factor to many diseases, including cancer. The increased incidence and aggressiveness of several cancers, including colorectal, postmenopausal breast, endometrial, prostate, esophageal, hematological, malignant melanoma, and renal carcinomas, result from obesity as a contributing factor. The increased morbidity and mortality of obesity-associated cancers are attributable to increased hormones, adipokines, and cytokines produced by the adipose tissue. The increased adipose tissue levels observed in obese patients result in more adipose stromal/stem cells (ASCs) distributed throughout the body. ASCs have been shown to impact cancer progression in vitro and in preclinical animal models. ASCs influence tumor biology via multiple mechanisms, including the increased recruitment of ASCs to the tumor site and increased production of cytokines and growth factors by ASCs and other cells within the tumor stroma. Emerging evidence indicates that obesity induces alterations in the biological properties of ASCs, subsequently leading to enhanced tumorigenesis and metastasis of cancer cells. As the focus of this review is the interaction and impact of ASCs on cancer, the presentation is limited to preclinical data generated on cancers in which there is a demonstrated role for ASCs, such as postmenopausal breast, colorectal, prostate, ovarian, multiple myeloma, osteosarcoma, cervical, bladder, and gastrointestinal cancers. Our group has investigated the interactions between obesity and breast cancer and the mechanisms that regulate ASCs and adipocytes in these different contexts through interactions between cancer cells, immune cells, and other cell types present in the tumor microenvironment (TME) are discussed. The reciprocal and circular feedback loop between obesity and ASCs and the mechanisms by which ASCs from obese patients alter the biology of cancer cells and enhance tumorigenesis will be discussed. At present, the evidence for ASCs directly influencing human tumor growth is somewhat limited, though recent clinical studies suggest there may be some link.

Management of HR+/HER2+ lobular breast cancer and trends do not mirror better outcomes

PURPOSE

Treatment protocols for invasive lobular breast cancer (ILC) have largely followed those for invasive ductal breast cancer. This study compares treatment outcomes of endocrine therapy versus combined chemo-endocrine therapy in hormone-receptor-positive (HR+), HER2-positive (HER2+) ILC tumors in a large national registry.

METHODS

We sampled the National Cancer Database (2010-2016) for female patients with stages I-III, HR+/HER2+ ILC who underwent surgery. Cochran-Armitage trend test examined trends of treatment regimen administration: Surgery only (S), chemotherapy (C), endocrine therapy (ET), and combined chemo-endocrine therapy (CET), with or without anti-HER2 therapy. Cox proportional hazard model were used to compare overall survival (OS) across ET and CET cohorts, stratifying for anti-HER2 therapy, before and after propensity score match of cohorts (2013-2016). Kaplan-Meier (KM) survival curves were also produced.

RESULTS

N=11,421 were included. 58.7% of patients received Anti-Her2 therapy after 2013. CET conferred better OS over ET in the unmatched (adjusted-5-year-OS: 92.5% vs. 81.1%, p<0.001) and PS-matched (90.4% vs. 84.5%, p=0.001) samples. ET caused lower OS in patients who received Anti-Her2 therapy (HR: 2.56, 95% CI: 1.60-4.12, p<0.001) and patients who did not (HR: 1.84, 95% CI: 1.21-2.78, p=0.004), as compared to CET on multivariable analysis. KM modeling showed highest OS in the CET cohort who received Anti-Her2 (93.0%), followed by the CET cohort who did not receive Anti-Her2 (90.2%) (p=0.06).

CONCLUSION

Chemotherapy followed by endocrine therapy and Anti-Her2 therapy was shown to be the most effective treatment modality in HR+/HER2+ ILC, contrasting previous data on the inconclusive benefit of chemotherapy in patients with ILC.

Precise, Genotype-First Breast Cancer Prevention: Experience With Transferring Monogenic Findings From a Population Biobank to the Clinical Setting

Although hereditary breast cancer screening and management are well accepted and established in clinical settings, these efforts result in the detection of only a fraction of genetic predisposition at the population level. Here, we describe our experience from a national pilot study (2018-2021) in which 180 female participants of Estonian biobank (of >150,000 participants in total) were re-contacted to discuss personalized clinical prevention measures based on their genetic predisposition defined by 11 breast cancer-related genes. Our results show that genetic risk variants are relatively common in the average-risk Estonian population. Seventy-five percent of breast cancer cases in at-risk subjects occurred before the age of 50 years. Only one-third of subjects would have been eligible for clinical screening according to the current criteria. The participants perceived the receipt of genetic risk information as valuable. Fluent cooperation of project teams supported by state-of-art data management, quality control, and secure transfer can enable the integration of research results to everyday medical practice in a highly efficient, timely, and well-accepted manner. The positive experience in this genotype-first breast cancer study confirms the value of using existing basic genomic data from population biobanks for precise prevention.

Immune Lymphocyte Infiltrate and its Prognostic Value in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) occurs more frequently in young (<50 years) non-Hispanic black and Hispanic/Latina women. It is considered the most aggressive subtype of breast cancer, although, recently, immune infiltrate has been associated with long-term survival, lower risk of death and recurrence, and response to neoadjuvant chemotherapy. The aim of this review was to evaluate the clinical impact of the immune infiltrate in TNBC by discussing whether its prognostic value varies across different populations. A comprehensive systematic search in databases such as PubMed and Web of Science was conducted to include papers focused on tumor-infiltrating lymphocytes (TILs) in TNBC in different population groups and that were published before January 2021. TNBC patients with higher levels of TILs had longer overall survival and disease-free survival times compared with TNBC patients with low TIL levels. Similar results were observed for CD4+, CD8+ TIL populations. On the other hand, patients with high TIL levels showed a higher rate of pathological complete response regardless of the population group (Asian, European, and American). These results altogether suggest that TIL subpopulations might have a prognostic role in TNBC, but the underlying mechanism needs to be elucidated. Although the prognosis value of TILs was not found different between the population groups analyzed in the revised literature, further studies including underrepresented populations with different genetic ancestries are still necessary to conclude in this regard.

The efficacy of tucatinib-based therapeutic approaches for HER2-positive breast cancer

Overexpression of human epidermal growth factor receptor 2 (HER2) occurs in approximately 15-20% of breast cancer cases. HER2 is a member of the epidermal growth factor receptor (EGFR) family with tyrosinase kinase activity, and its overexpression is linked to poor prognosis and shorter progression-free survival (PFS) and overall survival (OS). Among various treatment options, HER2-targeting monoclonal antibodies and tyrosine kinase inhibitors (TKIs) have mostly been applied in recent decades to treat HER2-positive (HER2+) breast cancer patients. Although positive clinical outcomes were documented in both advanced disease and neoadjuvant settings, the development of resistance mechanisms to such approaches has been one of the major challenges with the continuous usage of these drugs. In addition, patients who experience disease progression after treatment with multiple HER2-targeted therapies often have limited treatment options. The Food and Drug Administration (FDA) has recently approved a new TKI (i.e., tucatinib) for use in combination with immunotherapy and/or chemotherapeutic agents for the treatment of advanced-stage/metastatic HER2+ breast cancer. This review highlights recent updates on the efficacy of tucatinib-based therapeutic approaches in experimental models as well as in the clinical settings of HER2+ breast cancer.

A Single-Center Retrospective Analysis of Local and Distant Relapse of Breast Cancer Following Immediate Breast Reconstruction According to Molecular Subtypes

Purpose

Concerns have been raised about the oncologic safety of immediate breast reconstruction (IBR) following mastectomy for breast cancer. This study aimed to evaluate locoregional recurrence (LRR) and distant metastasis (DM) of breast cancer according to its molecular subtype in patients who underwent mastectomy alone or IBR after mastectomy.

Methods

In this retrospective cohort study, consecutive breast cancer patients treated by the single senior surgeon (XZ) between February 2010 and December 2014 were eligible. In total, 389 consecutive patients were included; 295 patients underwent mastectomy alone and 94 patients underwent mastectomy with IBR. Data were retrospectively collected and analyzed for LRR and DM stratified by molecular subtypes.

Results

With a median follow-up of 73 and 87.5 months, 1.69% of patients in the mastectomy alone group developed LRR compared to 0% in the reconstruction group (p = 0.342) and the total incidence of DMs was 11.52% in patients who received mastectomy alone and 7.44% in patients who received postmastectomy IBR (p = 0.262), respectively. The cumulative incidence of LRR was 2.1% vs. 0% for luminal A, 0% vs. 0% for luminal B, 0% vs. 0% for human epidermal growth factor receptor 2 (HER2)-enriched, and 4.5% vs. 0% for triple-negative in the mastectomy alone group compared to the postmastectomy IBR group. The cumulative incidence of DM was 15.5% vs. 5.7% for luminal A, 10% vs. 8.7% for luminal B, 17.3% vs. 0% for HER2-enriched, and 6.8% vs. 7.1% for triple-negative in the mastectomy alone group compared to the postmastectomy IBR group. On multivariable Cox regression analysis, lymph node metastasis was associated with an increased risk of DM in the mastectomy alone group (p = 0.03) and neoadjuvant chemotherapy was associated with an increased risk of DM in the postmastectomy IBR group (p = 0.021).

Conclusion

This study suggests that IBR does not have a negative impact on the LRR and DM of breast cancer according to molecular subtypes.

Cellular and molecular insights into the roles of visfatin in breast cancer cells plasticity programs

Obesity has reached a pandemic proportion and is responsible for the augmentation of multimorbidity including certain cancers. With the rise in obesity amongst the female population globally, a concomitant increase in breast cancer (BC) incidence and related mortality has been observed. In the present review, we have elucidated the cellular and molecular insight into the visfatin-mediated cellular plasticity programs such as Epithelial to mesenchymal transition (EMT) and Endothelial to mesenchymal transition (EndoMT), and stemness-associated changes in BC cells. EMT and EndoMT are responsible for inducing metastasis in cancer cells and conferring chemotherapy resistance, immune escape, and infinite growth potential. Visfatin, an obesity-associated adipokine implicated in metabolic syndrome, has emerged as a central player in BC pathogenesis. Several studies have indicated the presence of visfatin in the tumor microenvironment (TME) where it augments EMT and EndoMT of BC cells. Further, Visfatin also modulates the TME by acting on the tumor stroma cells such as adipocytes, infiltrated immune cells, and adipose-associated stem cells that secrete factors such as cytokines, and extracellular vesicles responsible for augmenting cellular plasticity program. Visfatin induced altered metabolism of the cancer cells and molecular determinants such as non-coding RNAs involved in EMT and EndoMT have been discussed. We have also highlighted specific therapeutic targets that can be exploited for the development of effective BC treatment. Taken together, these advanced understandings of cellular and molecular insight into the visfatin-mediated cellular plasticity programs may stimulate the development of better approaches for the prevention and therapy of BC, especially in obese patients.

Employment and risk of female breast cancer in Denmark

BACKGROUND

Occupational exposures may play a role in breast cancer etiology, and research focusing on identifying high-risk workplaces is important to advance the understanding and prevention of breast cancer.

METHODS

We undertook a population-based nested case-control study among women who were less than 70 years of age and born in Denmark, based on registry data including 38,375 breast cancer cases and 191,875 controls matched on year of birth, with information on lifetime work history. Odds ratios for women ever employed in a job branch were adjusted for socioeconomic status and reproductive variables.

RESULTS

Adjusted odds ratios of less than 0.75 were observed for several occupations in agriculture, hunting, forestry, and fishing, while increased risk patterns (odds ratios greater than 1.50) were noted for a number of production occupations, including employment in graphics and printing, and metal and machinery production. In services, several military professions were also associated with a high increased breast cancer risk.

CONCLUSIONS

The study shows a variation in the risk of female breast cancer by employment in different industrial and occupational sectors, and suggests that certain occupational exposures, for example, outdoor work, organic solvents, polycyclic aromatic hydrocarbons (PAHs), and night-shift work may play a role in the risk of breast cancer. Further hypothesis-testing studies focusing on these employments with a detailed assessment of specific occupational exposures are warranted.

Body size in early life and the risk of postmenopausal breast cancer

BACKGROUND

Greater early life adiposity has been reported to reduce postmenopausal breast cancer risk but it is unclear whether this association varies by tumour characteristics. We aimed to assess associations of early life body size with postmenopausal breast cancer and its subtypes, allowing for body size at other ages.

METHODS

A total of 342,079 postmenopausal UK women who reported their body size at age 10, clothes size at age 20, and body mass index (BMI) at baseline (around age 60) were followed by record linkage to national databases for cancers and deaths. Cox regression yielded adjusted relative risks (RRs) of breast cancer, overall and by tumour subtype, in relation to body size at different ages.

RESULTS

During an average follow-up of 14 years, 15,506 breast cancers were diagnosed. After adjustment for 15 potential confounders, greater BMI at age 60 was associated with an increased risk of postmenopausal breast cancer (RR per 5 kg/m2=1.20, 95%CI 1.18-1.22) whereas greater adiposity in childhood and, to a lesser extent, early adulthood, was associated with a reduced risk (0.70, 0.66-0.74, and 0.92, 0.89-0.96, respectively). Additional adjustment for midlife BMI strengthened associations with BMI at both age 10 (0.63, 0.60-0.68) and at age 20 (0.78, 0.75-0.81). The association with midlife adiposity was confined to hormone sensitive subtypes but early life adiposity had a similar impact on the risk of all subtypes.

CONCLUSION

Early life and midlife adiposity have opposite effects on postmenopausal breast cancer risk and the biological mechanisms underlying these associations are likely to differ.

Home mortgage discrimination and incidence of triple-negative and Luminal A breast cancer among non-Hispanic Black and non-Hispanic White females in California, 2006-2015

Purpose

In the United States, Black females are burdened by more aggressive subtypes and increased mortality from breast cancer compared to non-Hispanic (NH) White females. Institutional racism may contribute to these inequities. We aimed to characterize the association between home mortgage discrimination, a novel measure of institutional racism, and incidence of Luminal A and triple-negative breast cancer (TNBC) subtypes among NH Black and NH White females in California metropolitan areas.

Methods

We merged data from the California Cancer Registry on females aged 20 + diagnosed with primary invasive breast cancer between 2006 and 2015 with a census tract-level index of home mortgage lending bias measuring the odds of mortgage loan denial for Black versus White applicants, generated from the 2007–2013 Home Mortgage Disclosure Act database. Poisson regression estimated cross-sectional associations of census tract-level racial bias in mortgage lending with race/ethnicity- and Luminal A and TNBC-specific incidence rate ratios, adjusting for neighborhood confounders.

Results

We identified n = 102,853 cases of Luminal A and n = 15,528 cases of TNBC over the study period. Compared to NH Whites, NH Black females had higher rates of TNBC, lower rates of Luminal A breast cancer, and lived in census tracts with less racial bias in home mortgage lending. There was no evidence of association between neighborhood racial bias in mortgage lending at the time of diagnosis and either subtype among either racial/ethnic group.

Conclusion

Future research should incorporate residential history data with measures of institutional racism to improve estimation and inform policy interventions.

Cooperation between Angiogenesis, Vasculogenesis, Chemotaxis, and Coagulation in Breast Cancer Metastases Development: Pathophysiological Point of View

Simple Summary

Breast cancer is one of the main causes of morbidity and mortality in women. Early breast cancer has a relatively good prognosis, in contrast to metastatic disease with rather poor outcomes. Metastasis formation in distant organs is a complex process requiring cooperation of numerous cells, growth factors, cytokines, and chemokines. Tumor growth, invasion, and finally systemic spread are driven by processes of angiogenesis, vasculogenesis, chemotaxis, and coagulation. This review summarizes their role in development of distant metastases in breast cancer, as well as explains the essential processes occurring throughout these actions.

Abstract

With almost 2.3 million new cases and 685 thousand fatal events in 2020 alone, breast cancer remains one of the main causes of morbidity and mortality in women worldwide. Despite the increasing prevalence of the disease in recent years, the number of deaths has dropped—this is mostly the result of better diagnostic and therapeutic opportunities, allowing to recognize and treat breast cancer earlier and more efficiently. However, metastatic disease still remains a therapeutic challenge. As mechanisms of tumor spread are being explored, new drugs can be implemented in clinical practice, improving the outcomes in patients with advanced disease. Formation of metastases is a complex process, which involves activation of angiogenesis, vasculogenesis, chemotaxis, and coagulation. The actions, which occur during metastatic spread are interrelated and complementary. This review summarizes their importance and mutual connections in formation of secondary tumors in breast cancer.

Oral Contraceptive Use and Breast Cancer Risk According to Molecular Subtypes Status: A Systematic Review and Meta-Analysis of Case-Control Studies

We conducted a systematic review and meta-analysis to investigate the effect of oral contraceptives (OCs) on risk of breast cancer (BrCa) by status of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). We searched the MEDLINE (PubMed), Embase and the Cochrane Library database and bibliographies of pertinent articles published up to 2020. Therein, we identified nineteen eligible case-control studies which provided data by breast cancer subtypes: ER-positive (ER+), ER-negative (ER−), HER2-positive (HER2+) and Triplet-negative (TN). Summary risk estimates (pooled OR [pOR]) and 95% confidence intervals (CIs) were calculated using fixed/random effects models. The summary meta-analysis showed that over-use of OCs led to significant increased risk of TNBrCa (OR = 1.37, 95% CI; 1.13 to 1.67, p = 0.002), as well as of ER−BrCa (OR = 1.20, 95% CI: 1.03 to 1.40, p = 0.019). There was also a significant reduction in the risk of ER+BrCa (OR = O.92, 95% CI: 0.86 to 0.99, p = 0.026,) and a slight reduction in the risk of HER2+BrCa (OR = 0.95, 95% CI; 0.79 to 1.14, p = 0.561) after taking OCs. Meta-analysis indicated that OC use has different impacts on risk of breast cancer subtypes defined by receptor status. The identified differences between individual subtypes of breast cancer may reflect different mechanisms of carcinogenesis.

Exposure to airborne cadmium and breast cancer stage, grade and histology at diagnosis: findings from the E3N cohort study

Molecular studies suggest that cadmium due to its estrogenic properties, might play a role in breast cancer (BC) progression. However epidemiological evidence is limited. This study explored the association between long-term exposure to airborne cadmium and risk of BC by stage, grade of differentiation, and histological types at diagnosis. A nested case-control study of 4401 cases and 4401 matched controls was conducted within the French E3N cohort. A Geographic Information System (GIS)-based metric demonstrated to reliably characterize long-term environmental exposures was employed to evaluate airborne exposure to cadmium. Multivariable adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using conditional logistic regression models. There was no relationship between cadmium exposure and stage of BC. Also, no association between cadmium exposure and grade of differentiation of BC was observed. However, further analyses by histological type suggested a positive association between cadmium and risk of invasive tubular carcinoma (ITC) BC [OR_{Q5 vs Q1} = 3.4 (95% CI 1.1-10.7)]. The restricted cubic spline assessment suggested a dose-response relationship between cadmium and ITC BC subtype. Our results do not support the hypothesis that airborne cadmium exposure may play a role in advanced BC risk, but suggest that cadmium may be associated with an increased risk of ITC.

Historical Trends in Incidence of Breast Cancer in Shanghai, Hong Kong and Los Angeles, 1973-2012: A Joinpoint and Age-Period-Cohort Analysis

Objectives: This study aimed to estimate the long-term trends of breast cancer incidence in Shanghai, Hong Kong, and Los Angeles (LA).

Methods: Data were obtained from Cancer Incidence in Five Continents (CI5plus) database. The average annual percent change (AAPC) was conducted by joinpoint regression analysis, and the age, period and cohort effects were estimated by age-period-cohort (APC) analysis.

Results: The age-standardized incidence rates (ASIRs) in LA were higher than Shanghai and Hong Kong. During 1988–2012, the ASIRs significantly decreased in white women in LA (AAPC = −0.6%, 95% CI: −0.9% to −0.4%) while increased in Shanghai (2.5%: 2.1%–2.9%) and Hong Kong (2.2%: 2.0%–2.5%). The APC analysis revealed significantly increased effects of age and period, and decreased effect of birth cohort.

Conclusion: Although age and cohort effects were relatively strong, the period effect may be the key factor affecting trends of incidence, which may be caused by increasing exposures to carcinogens and risk factors. Therefore, more effective measures should be carried out promptly to protect high-risk populations such as elder women, to avoid exposures to risk factors of breast cancer.

Premenopausal Breast Cancer Risk Factors and Associations with Molecular Subtypes: A Case-Control Study

Background

Breast cancer (BC) is the most prevalent cancer in women and the leading cause of women's cancer-related deaths and morbidity worldwide. In Rwanda, BC incidence is increasing with an unacceptably high mortality rate in premenopausal women.

Objectives

The purpose was to identify modifiable BC risk factors and assess associations between common breast cancer risks factors and molecular subtypes in premenopausal women in Rwanda.

Methods

This was a case-control study. Premenopausal women with histological confirmation of BC and frequency-matched for age controls were recruited. A preestablished questionnaire was administered to both cases and controls for sociodemographics, BC probable risk factors, and clinical and pathological characteristics. BC was classified into luminal A, luminal B, HER2-type, basal-like (triple negative), and unclassified molecular subtypes by immunohistochemistry (IHC). Odds ratio (OR) and 95% confidence interval (CI) were estimated using multivariate logistic regression analysis.

Results

340 participants were recruited into the study (170 cases vs. 170 controls). The median age was 39 years. The majority of cases presented at advanced stages of the disease (51.2% in stages III and IV) and had invasive ductal carcinoma (98.2%). 60.6% had subtypes of poor prognosis (HER2 enriched 14.7%, triple negative 12.9%, and unclassified 32.9%). Alcohol intake (AOR = 3.73, 95%CI 2.19 - 6.32, p < 0.001), obesity/overweight in adolescence or early adulthood (AOR = 10.86, 95%CI 4.82 - 24.4, p < 0.001), history of primary infertility (AOR = 33.8, 95%CI 3.5 - 321.5, p = 0.002), nulliparity (AOR = 3.75, 95%CI 1.61 - 8.75, p = 0.002), and a history of benign breast disease (AOR = 6.06, 95%CI 1.19 - 30.73, p = 0.03) were associated with the occurrence of premenopausal breast cancer. There was no significant difference between risk factor stratification per molecular subtype.

Conclusion

Several reproductive, environmental, and lifestyle risk factors have been identified to be associated with premenopausal BC. Among them, alcohol intake and obesity/overweight during adolescence/early adulthood can be modified. Interventions targeting alcohol consumption and obesity/overweight in adolescents and young adults may decrease the incidence of premenopausal breast cancer.

Risk factors for breast cancer subtypes among Black women undergoing screening mammography

PURPOSE

Black women are more likely than non-Hispanic White women to be diagnosed with triple negative breast cancer (TNBC), an aggressive subtype with limited treatment options. The study objective was to evaluate the associations of known breast cancer risk factors, including breast density, with TNBC among Black women.

METHODS

This study included Black women who underwent screening mammography between the ages of 40-84 years at a University of Pennsylvania Health System between 2010 and 2015. Cox proportional hazard models using multiple imputation with chained equations were used to estimate hazard ratios and 95% confidence intervals for risk factors for ER/PR+/HER2- and TNBC.

RESULTS

Among 25,013 Black women, there were 330 incident breast cancers (1.3%) during a mean follow-up of 5.8 years; 218 (66.1%) ER/PR+ HER- and 61 (18.1%) TNBC. Having dense breasts (heterogeneously dense or extremely dense) vs. non-dense breasts (almost entirely fatty or scattered areas of fibroglandular density) increased risk of ER/PR+/HER2- breast cancer almost 80% (HR 1.79, 95% CI 1.32-2.43) and TNBC more than twofold (HR 2.53, 1.45-4.44). Older age was associated with an increased risk for ER/PR+/HER2- (HR 1.04, 1.03-1.06) and TNBC (HR 1.03, 1.00-1.05). Having a BMI of > 30 kg/m² was associated with an increased risk (HR 2.77, 1.05-7.30) for TNBC and an increased risk of ERPR+/HER2- breast cancer in postmenopausal but not pre-menopausal women (p-interaction = 0.016).

CONCLUSION

Our results suggest that breast density and obesity are strong risk factors for TNBC among Black women. Understanding breast cancer subtype specific risk factors among Black women can help improve risk assessment.

Healthful and Unhealthful Plant-Based Diets and Risk of Breast Cancer in U.S. Women: Results from the Nurses' Health Studies

BACKGROUND

Plant-based diets have been associated with lower risk of various diseases, including type 2 diabetes, cardiovascular disease, and other cardiometabolic risk factors. However, the association between plant-based diet quality and breast cancer remains unclear.

METHODS

We prospectively followed 76,690 women from the Nurses' Health Study (NHS, 1984-2016) and 93,295 women from the NHSII (1991-2017). Adherence to an overall plant-based diet index (PDI), a healthful PDI (hPDI), and an unhealthful PDI (uPDI) was assessed using previously developed indices. Cox proportional hazards models were used to estimate HR and 95% confidence intervals (CI) for incident invasive breast cancer.

RESULTS

Over 4,841,083 person-years of follow-up, we documented 12,482 incident invasive breast cancer cases. Women with greater adherence to PDI and hPDI were at modestly lower risk of breast cancer [(HRQ5 vs. Q1, 0.89; 95% CI, 0.84-0.95); (HRQ5 vs. Q1, 0.89; 95% CI, 0.83-0.94)]. We observed significant heterogeneity by estrogen receptor (ER) status, with the strongest inverse association between hPDI and breast cancer observed with ER-negative tumors [HRQ5 vs. Q1, 0.77; 95% CI, 0.65-0.90; P trend < 0.01]. We also found an inverse association between extreme quintiles of healthy plant foods and ER-negative breast cancer [HR, 0.74; 95% CI, 0.61-0.88; P trend < 0.01].

CONCLUSIONS

This study provides evidence that adherence to a healthful plant-based diet may reduce the risk of breast cancer, especially those that are more likely to be aggressive tumors.

IMPACT

This is the first prospective study investigating the relation between healthful and unhealthful plant-based dietary indices and risk of total and subtype-specific breast cancer.

Impact of Stilbenes as Epigenetic Modulators of Breast Cancer Risk and Associated Biomarkers

With the recent advancement of genetic screening for testing susceptibility to mammary oncogenesis in women, the relevance of the gene−environment interaction has become progressively apparent in the context of aberrant gene expressions. Fetal exposure to external stressors, hormones, and nutrients, along with the inherited genome, impact its traits, including cancer susceptibility. Currently, there is increasing interest in the role of epigenetic biomarkers such as genomic methylation signatures, plasma microRNAs, and alterations in cell-signaling pathways in the diagnosis and primary prevention of breast cancer, as well as its prognosis. Polyphenols like natural stilbenes have been shown to be effective in chemoprevention by exerting cytotoxic effects that can stall cell proliferation. Besides possessing antioxidant properties against the DNA-damaging effects of reactive oxygen species, stilbenes have also been observed to modulate cell-signaling pathways. With the increasing trend of early-life screening for hereditary breast cancer risks, the potency of different phytochemicals in harnessing the epigenetic biomarkers of breast cancer risk demand more investigation. This review will explore means of exploiting the abilities of stilbenes in altering the underlying factors that influence breast cancer risk, as well as the appearance of associated biomarkers.

Three photoinitiators induce breast tumor growth in mouse xenografts with MCF-7 breast cancer cells

Photoinitiators are utilized in the production of a wide range of commonly used products. However, some photoinitiators exert toxic effects. We previously demonstrated the endocrine-disrupting effects of photoinitiators in vitro. The present study investigated the estrogenic activities of three photoinitiators: 1-hydroxycyclohexyl phenyl ketone (1-HCHPK), methyl 2-benzoylbenzoate (MBB), and 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MTMP), which were subcutaneously injected into mouse xenografts with MCF-7 breast cancer cells. The results obtained showed that 1-HCHPK, MBB, and MTMP promoted breast tumor growth in these xenografts. A pretreatment with the estrogen receptor antagonist tamoxifen blocked the tumor growth-promoting effects of each photoinitiator. Collectively, the present results suggest that the three photoinitiators exhibit estrogenic agonist activities in vivo. Furthermore, as a factor for breast tumor growth, these photoinitiators potentially have estrogenic properties in vivo.

Relationship of established risk factors with breast cancer subtypes

Background

Breast cancer is a heterogeneous disease, divided into subtypes based on the expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Subtypes have different biology and prognosis, with accumulating evidence of different risk factors. The purpose of this study was to compare breast cancer risk factors across tumor subtypes in a large, diverse mammography population.

Methods

Women aged 40–84 without a history of breast cancer with a screening mammogram at three United States health systems from 2006 to 2015 were included. Risk factor questionnaires were completed at mammogram visit, supplemented by electronic health records. Invasive tumor subtype was defined by immunohistochemistry as ER/PR+HER2−, ER/PR+HER2+, ER, and PR−HER2+, or triple‐negative breast cancer (TNBC). Cox proportional hazards models were run for each subtype. Associations of race, reproductive history, prior breast problems, family history, breast density, and body mass index (BMI) were assessed. The association of tumor subtypes with screen detection and interval cancer was assessed using logistic regression among invasive cases.

Results

The study population included 198,278 women with a median of 6.5 years of follow‐up (IQR 4.2–9.0 years). There were 4002 invasive cancers, including 3077 (77%) ER/PR+HER2−, 300 (8%) TNBC, 342 (9%) ER/PR+HER2+, and 126 (3%) ER/PR−HER2+ subtype. In multivariate models, Black women had 2.7 times higher risk of TNBC than white women (HR = 2.67, 95% CI 1.99–3.58). Breast density was associated with increased risk of all subtypes. BMI was more strongly associated with ER/PR+HER2− and HER2+ subtypes among postmenopausal women than premenopausal women. Breast density was more strongly associated with ER/PR+HER2− and TNBC among premenopausal than postmenopausal women. TNBC was more likely to be interval cancer than other subtypes.

Conclusions

These results have implications for risk assessment and understanding of the etiology of breast cancer subtypes. More research is needed to determine what factors explain the higher risk of TNBC for Black women.

Evaluation of lifestyle risk factor differences in global patterns of breast cancer mortality and DALYs during 1990-2017 using hierarchical age-period-cohort analysis

BACKGROUND

Statistical evidence on breast cancer (BC) burden related to health and lifestyle risk factors are valuable for health policy-making. This study aimed to compare the trends in BC mortality and disability adjusted life years (DALYs) attributable to various health and life style risk factors among different world's regions according to sociodemographic index (SDI).

METHODS

We extracted the age-standardized and age-specific rate of mortality and DALYs of women BC during 1990-2017 using the comparative risk assessment framework of the 2017 global burden of disease (GBD) study. We performed hierarchical age-period-cohort analysis to estimate age- and time-related trends, and effect of interactions between different risk factors on BC risk.

RESULTS

During 1990-2017, the age-standardized rate of mortality and DALYs of women BC was increasing in less developed and under developing regions. The risk factor alcohol use [RR 51.3(95%CI 17.6-149.7)] and smoking [5.9(2.0-17.3)] were significantly highly contributor to increased mortality risk in high SDI region. Whereas in the low-SDI region, the greater mortality risk was observed in alcohol use [6.9(2.4-17)] and high FPG [2.7(1.5-3.1)]-related deaths. The adjusting for individual age, period, and risk factor effects, the significant interaction effect between metabolic risk factors and older ages were observed in all SDI regions and globally as well. However, an increasing cohort effect of alcohol, high fasting plasma glucose (FPG) and smoking-related death, and DALYs was observed during 1960 to 1985 cohorts among low-SDI regions.

CONCLUSIONS

The age-standardized rates of mortality and DALYs due to BC has been increasing in low-SDI region. Alcohol consumption, high body mass index (BMI), high FPG, and smoking are potential BC risk factors particularly in older ages that leading to adverse disease outcomes. Therefore, rapid aging and prevalence of these prospective risk factors may strengthen the increasing mortality and DALYs of BC in low-SDI region. Hence, preventive measure along with strict action against concerned BC risk factors should be taken to reduce the disease burden specifically among lower-SDI regions.

Early Alcohol Use Initiation, Obesity, Not Breastfeeding, and Residence in a Rural Area as Risk Factors for Breast Cancer: A Case-Control Study

Simple Summary

Breast cancer became the most common cancer globally in 2021, according to the World Health Organization. The aim of the study was to evaluate risk factors for breast cancer, such as early alcohol use initiation, obesity, breastfeeding, and place of residence. The effect of alcohol consumption by girls has been assessed in only a few studies and is not fully understood. In this study, it has been found to be associated with a higher risk of breast cancer. Our study also shed light on the incidence disparity—women were more at risk in the countryside than in the city. The results of this study should be included in the preparation of breast cancer prevention programs and also aimed at women in adolescence and early adulthood because exposures during childhood and adolescence can affect a woman’s long-term risk of breast cancer. Every effort should also be made to ensure that access to knowledge is open to all, regardless of where they live, giving all women equal opportunities.

Abstract

The aim of this study was to determine the risk factors for breast cancer in the Polish population. In total, 201 Polish women newly diagnosed with breast cancer and 201 one-to-one age-matched healthy controls participated in this case-control study. Data on sociodemographic characteristics, reproductive and menstrual history, medical history, lifestyle factors, and anthropometric measurements were collected by the interviewers. Odds ratios and 95% confidence intervals were obtained using multivariate unconditional logistic regression models controlling for potential confounders. Significant relationships were observed between BMI, alcohol use initiation, breastfeeding, education, and place of residence. Obese women had a higher risk of breast cancer than women with a BMI < 30 (OR = 1.9; 95% CI: 1.16 to 3.04). Early alcohol use initiation (≤15 years) was associated with an almost two-fold higher risk of breast cancer (OR = 1.98, 95% CI: 1.06 to 3.69). Breastfeeding for less than 3 months (OR = 2.3, 95% CI: 1.52 to 3.5), receiving a basic and vocational education (OR = 2.5, 95% CI: 1.49 to 4.19), and living in a rural area (OR = 1.7, 95% CI: 1.05 to 2.9) increased the risk of breast cancer. Prevention activities for breast cancer are already needed in adolescents and young women. A much greater emphasis should also be placed on breast cancer prevention campaigns in rural areas in Poland.

Theory, methods, and operational results of the Young Women's Health History Study: a study of young-onset breast cancer incidence in Black and White women

Purpose

The etiology of young-onset breast cancer (BC) is poorly understood, despite its greater likelihood of being hormone receptor-negative with a worse prognosis and persistent racial and socioeconomic inequities. We conducted a population-based case–control study of BC among young Black and White women and here discuss the theory that informed our study, exposures collected, study methods, and operational results.

Methods

Cases were non-Hispanic Black (NHB) and White (NHW) women age 20–49 years with invasive BC in metropolitan Detroit and Los Angeles County SEER registries 2010–2015. Controls were identified through area-based sampling from the U.S. census and frequency matched to cases on study site, race, and age. An eco-social theory of health informed life-course exposures collected from in-person interviews, including socioeconomic, reproductive, and energy balance factors. Measured anthropometry, blood (or saliva), and among cases SEER tumor characteristics and tumor tissue (from a subset of cases) were also collected.

Results

Of 5,309 identified potentially eligible cases, 2,720 sampled participants were screened and 1,812 completed interviews (682 NHB, 1140 NHW; response rate (RR): 60%). Of 24,612 sampled control households 18,612 were rostered, 2,716 participants were sampled and screened, and 1,381 completed interviews (665 NHB, 716 NHW; RR: 53%). Ninety-nine% of participants completed the main interview, 82% provided blood or saliva (75% blood only), and SEER tumor characteristics (including ER, PR and HER2 status) were obtained from 96% of cases.

Conclusions

Results from the successfully established YWHHS should expand our understanding of young-onset BC etiology overall and by tumor type and identify sources of racial and socioeconomic inequities in BC.

Supplementary Information

The online version of this article contains supplementary material available (10.1007/s10552-021-01461-x).

Prevalence and Molecular Profile of Breast Carcinoma Using Immunohistochemistry Markers in Mexican Women

Background

In Mexico, breast cancer is the leading cause of death by malignant tumors in women aged 20 and older. The World Health Organization estimates that 69% of deaths caused by breast cancer occur in developing countries. Little is known about the prevalence of breast carcinoma in Mexico and its molecular subclassification.

Methods

This retrospective cross-sectional study included patients who underwent a mastectomy (single, radical or lumpectomy) or a breast tumor biopsy (core-needle or excisional) from January 2002 to December 2018. The primary purpose of the study was to determine the prevalence and molecular profile of breast in comprehensive cancer center in Mexico and compare our results with those published in the US. This study was approved by our scientific and bioethical committee.

Results

The final analysis included 379 patients. The youngest patient was 23 years old and the oldest patient was 89; the mean age at diagnosis was 54.63 years. Patients of 40 years old or younger accounted for 48 of the cases (12.66%) and those older than 40 accounted for 331 of the cases (87.33%). The molecular subclassification showed luminal A subtype in 139 cases (36.67%), luminal B subtype in 143 cases (37.73%), human epidermal growth factor receptor 2-positive carcinomas in 32 cases (8.44%) and triple-negative carcinomas in 65 cases (17.15%). Diabetes mellitus was present in 43 patients (11.34%), hypertension in 78 patients (20.58%), obesity in 82 patients (21.63%) and 66 patients reported being treated with exogenous hormone therapy (17.41%).

Conclusions

Breast carcinoma occurs at an earlier age in Mexican women compared to women in the US. Hormone-positive tumors were found to be more prevalent in older patients, while high-grade tumors were more frequently identified in younger patients.

Breast Cancer Risk Assessment: A Review on Mammography-Based Approaches

Breast cancer affects thousands of women across the world, every year. Methods to predict risk of breast cancer, or to stratify women in different risk levels, could help to achieve an early diagnosis, and consequently a reduction of mortality. This paper aims to review articles that extracted texture features from mammograms and used those features along with machine learning algorithms to assess breast cancer risk. Besides that, deep learning methodologies that aimed for the same goal were also reviewed. In this work, first, a brief introduction to breast cancer statistics and screening programs is presented; after that, research done in the field of breast cancer risk assessment are analyzed, in terms of both methodologies used and results obtained. Finally, considerations about the analyzed papers are conducted. The results of this review allow to conclude that both machine and deep learning methodologies provide promising results in the field of risk analysis, either in a stratification in risk groups, or in a prediction of a risk score. Although promising, future endeavors in this field should consider the possibility of the implementation of the methodology in clinical practice.

Factors affecting medical healthcare-seeking behaviours of female patients according to their stage of being diagnosed with breast cancer

OBJECTIVE

The aim of study was to determine factors affecting the medical healthcare-seeking behaviours of female patients according to their stage of being diagnosed with breast cancer.

METHODS

This descriptive and correlational study was carried out with 150 women. The data were collected by a survey form, the Body Perception Scale, the Rosenberg Self-Esteem Scale and the Social Appearance Anxiety Scale.

RESULTS

About 54% of the women were diagnosed with early-stage breast cancer, 68.7% had high self-esteem, and 80% had positive body perceptions, while their social appearance anxiety levels were moderate. The patients with breast cancer at the 4th stage had a high body perception score of 174.00 ± 23.34. Self-esteem was the highest in the patients with stage 2B breast cancer with a value of 0.61 ± 0.91. The highest social anxiety mean score was found in the patients with stage 2A breast cancer as 31.65 ± 12.50. There was no statistically significant difference in the women's sociodemographic characteristics, health and breast cancer history, self-esteem, body perception and social appearance anxiety based on their stages of cancer (p > 0.05).

CONCLUSION

Nurses' identification of risky individuals in early diagnosis, information for the individual / family and society by planning trainings and raising awareness will contribute positively to the patients' medical health-seeking behaviours.

Breast cancer among Danish women occupationally exposed to diesel exhaust and polycyclic aromatic hydrocarbons, 1964-2016

Objective:

The aim of this study was to explore the association between occupational exposure to diesel exhaust and polycyclic aromatic hydrocarbons (PAH), respectively, and breast cancer subtypes.

Methods:

The study included 38 375 women <70 years with incident breast cancer, identified in the Danish Cancer Registry, and 5 breast cancer-free controls per case who were randomly selected from the Danish Civil Registration System and matched on year of birth. Full employment history was obtained for all study subjects from a nationwide pension fund, and exposure to diesel exhaust and PAH was assessed using a job exposure matrix. Conditional logistic regression was used for estimation of odds ratios (OR) with adjustment for reproductive factors and socioeconomic status.

Results:

No noteworthy associations were observed for overall breast cancer in women exposed to diesel exhaust. However, diesel exhaust modestly elevated the risk of estrogen receptor negative breast tumors before age 50 [OR 1.26, 95% confidence interval (CI) 1.09–1.46]. Duration– and dose–response relationships were further observed for this subtype in this age group. No notable risk patterns were generally observed for PAH exposure.

Conclusion:

Occupational exposure to diesel exhaust may increase the risk of early-onset estrogen receptor negative breast tumors in women. Future studies exploring this association are warranted.

Assessment of Human Papillomavirus Infection and Risk Factors in Egyptian Women With Breast Cancer

Numerous risk factors for breast cancer (BC) have been identified. High-risk human papilloma virus (HR-HPV) is the etiological agent of cervical cancer and in some cases of head and neck cancer, specifically oropharyngeal cancer, but the role of HR-HPV in evoking neoplasia in BC is still unclear. In this study, all women above the age of 18 visiting the oncology clinic at Al-Azhar university hospital and Ain Shams specialized hospital between the period of February 2017 and March 2018 were invited to participate. We determined the prevalence of HR-HPV genotypes 16, 18, and 31 in breast tissue samples from 72 women with treatment-naïve BC and 15 women with benign breast lesions (BBL) by quantitative real-time PCR (qRT-PCR) and primer sets targeting the E6 and E7 regions. High-risk human papilloma virus DNA was detected in 16 of 72 (22.2%) BC cases (viral load range = 0.3-237.8 copies/uL) and 0 of 15 women with BBL. High-risk human papilloma virus was detected in 14 of 16 (87.5%), 2 of 16 (12.5%), and 0 of 16 (0%) for genotypes 16, 18, and 31, respectively. Forty-three age-matched healthy Egyptian women were enrolled as controls for assessment of local risk factors that can be used to initiate a strategy of BC prevention in Egypt. Assessment of the risk factors demonstrated that low education level, passive smoking, lack of physical activity, family history of cancer, and use of oral contraception were significant risk factors for BC. In conclusion, our results lead us to postulate that HR-HPV infection may be implicated in the development of some types of BC in Egyptian women. In addition, identification of local risk factors can support practical prevention strategies for BC in Egypt.

Anticancer Activity of the Acetylenic Derivative of Betulin Phosphate Involves Induction of Necrotic-Like Death in Breast Cancer Cells In Vitro

Betulin (BT) is a natural pentacyclic lupane-type triterpene exhibiting anticancer activity. Betulin derivatives bearing propynoyloxy and phosphate groups were prepared in an effort to improve the availability and efficacy of the drug. In this study, a comparative assessment of the in vitro anticancer activity of betulin and its four derivatives was carried out using two human breast cancer cell lines: SK-BR-3 and MCF-7. In both studied cell lines, 30-diethoxyphosphoryl-28-propynoylbetulin (compound 4) turned out to be the most powerful inhibitor of growth and inducer of cellular death. Detailed examination of that derivative pertained to the mechanisms underlying its anticancer action. Treatment with compound 4 decreased DNA synthesis and up-regulated p21^WAF1/Cip1 mRNA and protein levels in both cell lines. On the other hand, that derivative caused a significant increase in cell death, as evidenced by increased lactate dehydrogenase (LDH) release and ethidium homodimer uptake. Shortly after the compound addition, an increased generation of reactive oxygen species and loss of mitochondrial membrane potential were detected. The activation of caspase-3 and fragmentation of genomic DNA suggested an apoptotic type of cell death. However, analysis of cellular morphology did not reveal any nuclear features typical of apoptosis. Despite necrosis-like morphology, dead cells exhibited activation of the cascade of caspases. These observations have led to the conclusion that compound 4 pushed cells to undergo a form of necrotic-like regulated cell demise.

Nonpalpable breast lesions: impact of a second-opinion review at a breast unit on BI-RADS classification

OBJECTIVE

To compare BI-RADS classification, management, and outcome of nonpalpable breast lesions assessed both by community practices and by a multidisciplinary tumor board (MTB) at a breast unit.

METHODS

All nonpalpable lesions that were first assigned a BI-RADS score by community practices and then reassessed by an MTB at a single breast unit from 2009 to 2017 were retrospectively reviewed. Inter-review agreement was assessed with Cohen's kappa statistic. Changes in biopsy recommendation were calculated. The percentage of additional tumor lesions detected by the MTB was obtained. The sensitivity, AUC, and cancer rates for BI-RADS category 3, 4, and 5 lesions were computed for both reviews.

RESULTS

A total of 1909 nonpalpable lesions in 1732 patients were included. For BI-RADS scores in the whole cohort, a fair agreement was found (κ = 0.40 [0.36-0.45]) between the two reviews. Agreement was higher when considering only mammography combined with ultrasound (κ = 0.53 [0.44-0.62]), masses (κ = 0.50 [0.44-0.56]), and architectural distortion (κ = 0.44 [0.11-0.78]). Changes in biopsy recommendation occurred in 589 cases (31%). Ninety of 345 additional biopsies revealed high-risk or malignant lesions. Overall, the MTB identified 27% additional high-risk and malignant lesions compared to community practices. The BI-RADS classification AUCs for detecting malignant lesions were 0.66 (0.63-0.69) for community practices and 0.76 (0.75-0.78) for the MTB (p < 0.001).

CONCLUSION

Agreement between community practices and MTB reviews for BI-RADS classification in nonpalpable lesions is only fair. MTB review improves diagnostic performances of breast imaging and patient management.

KEY POINTS

• The inter-review agreement for BI-RADS classification between community practices and the multidisciplinary board was only fair (κ = 0.40). • Disagreements resulted in changes of biopsy recommendation in 31% of the lesions. • The multidisciplinary board identified 27% additional high-risk and malignant lesions compared to community practices.