Incidence Of Invasive Breast Cancer Research Articles

The role of ethnic enclaves and neighborhood socioeconomic status in invasive breast cancer incidence rates among Asian American, Native Hawaiian, and Pacific Islander females in California.

Few studies have examined whether the incidence rates of invasive breast cancer among Asian American, Native Hawaiian, and Pacific Islander (AANHPI) populations differ by the neighborhood social environment. Thus, we examined associations of ethnic enclave and neighborhood socioeconomic status (nSES) with breast cancer incidence rates among AANHPI females in California. A total of 14,738 AANHPI females diagnosed with invasive breast cancer in 2008-2012 were identified from the California Cancer Registry. AANHPI ethnic enclaves (culturally distinct neighborhoods) and nSES were assessed at the census tract level using 2007-2011 American Community Survey data. Breast cancer age-adjusted incidence rates and incidence rate ratios (IRRs) were estimated for AANHPI ethnic enclave, nSES, and their joint effects. Subgroup analyses were conducted by stage of disease. The incidence rate of breast cancer among AANHPI females living in lowest ethnic enclave neighborhoods (quintile (Q)1) were 1.21 times (95% Confidence Interval (CI) 1.11, 1.32) that of AANHPI females living highest ethnic enclave neighborhoods (Q5). In addition, AANHPI females living in highest vs. lowest SES neighborhoods had higher incidence rates of breast cancer (Q5 vs. Q1 IRR = 1.30, 95% CI 1.22 to 1.40). The incidence rate of breast cancer among AANHPI females living in low ethnic enclave + high SES neighborhoods was 1.32 times (95% CI 1.25, 1.39) that of AANHPI females living in high ethnic enclave + low SES neighborhoods. Similar patterns of associations were observed for localized and advanced stage disease. For AANHPI females in California, incidence rates of breast cancer differed by nSES, ethnic enclave, when considered independently and jointly. Future studies should examine whether the impact of these neighborhood-level factors on breast cancer incidence rates differ across specific AANHPI ethnic groups and investigate the pathways through which they contribute to breast cancer incidence.

Changes in breast cancer incidence and surgical treatment in Baden–Württemberg (Germany) during the COVID-19 pandemic

The COVID-19 pandemic affected the diagnostics and treatment of breast cancer. Numerous studies reported an early decline in breast cancer (BC) incidence during the COVID-19 pandemic. Less evidence is available on changes in medical care. Reports from individual patients have provided anecdotal evidence for a shift from breast-conserving surgery to mastectomy to reduce the number of visits to radiation units during the pandemic. This study aimed to explore changes in BC incidence and surgical treatment in the south of Germany. Using data from the Baden-Württemberg Cancer Registry, the age-standardized incidence of BC (ICD-10 C50 and D05) (women) in 2018–2021 was investigated overall and by age and stage using standardized incidence ratios. Among pre-operative stage I/IIA BC patients, differences in the time to surgery and type of surgery were investigated using negative binomial and logistic regression models. The incidence of invasive BC decreased significantly from 170.9 per 100,000 women in 2018/2019 to 159.7 in 2020 and increased to 169.2 in 2021. This decrease resulted from a lower incidence around April 2020 and was also observed for non-invasive BC. In 2021, incidence of invasive BC was still decreased by 8% in women aged 80 + years. Surgical treatment was analyzed in 22,708 BC patients with a pre-operative stage ≤ IIA. The median time to surgery was 33 days in 2018/2019, 32 days in 2020 and 36 days in 2021. The proportion of mastectomies increased from 16.1% in 2018/2019 to 17.1% in 2020 and 17.3% in 2021 (adjusted odds ratio and 95% confidence interval (2021 vs. 2018/2019): 1.13 (1.03–1.24)). The adjusted increase was strongest for patients aged 50–59 years (1.34 (1.09–1.64)) and those with high-grade tumors (1.27 (1.07–1.51)). While the early return to pre-pandemic age-standardized BC incidence rates is promising, missed cases have not been caught up until 2021. Furthermore, the decreased incidence in elderly women in 2021 warrants further attention. In early-stage BC, a slightly greater rate of mastectomies was observed, although such a change was not recommended. This result underlines the importance of good communication of adapted treatment guidelines in such exceptional circumstances.

Random effects models of tumour growth for investigating interval breast cancer.

In Nordic countries and across Europe, breast cancer screening participation is high. However, a significant number of breast cancer cases are still diagnosed due to symptoms between screening rounds, termed "interval cancers". Radiologists use the interval cancer proportion as a proxy for the screening false negative rate (ie, 1-sensitivity). Our objective is to enhance our understanding of interval cancers by applying continuous tumour growth models to data from a study involving incident invasive breast cancer cases. Building upon previous findings regarding stationary distributions of tumour size and growth rate distributions in non-screened populations, we develop an analytical expression for the proportion of interval breast cancer cases among regularly screened women. Our approach avoids relying on estimated background cancer rates. We make specific parametric assumptions concerning tumour growth and detection processes (screening or symptoms), but our framework easily accommodates alternative assumptions. We also show how our developed analytical expression for the proportion of interval breast cancers within a screened population can be incorporated into an approach for fitting tumour growth models to incident case data. We fit a model on 3493 cases diagnosed in Sweden between 2001 and 2008. Our methodology allows us to estimate the distribution of tumour sizes at the most recent screening for interval cancers. Importantly, we find that our model-based expected incidence of interval breast cancers aligns closely with observed patterns in our study and in a large Nordic screening cohort. Finally, we evaluate the association between screening interval length and the interval cancer proportion. Our analytical expression represents a useful tool for gaining insights into the performance of population-based breast cancer screening programs.

Breast cancer incidence, stage distribution, and treatment shifts during the 2020 COVID-19 pandemic: a nationwide population-level study

BackgroundThe first COVID-19 wave in 2020 necessitated temporary suspension of non-essential medical services including organized cancer screening programs in Belgium. This study assessed the impact of the pandemic on breast cancer (BC) incidence, stage at diagnosis, and management in Belgium in 2020.MethodsAll Belgian residents diagnosed with in situ or invasive BC in 2015–2020 in the nationwide, population-based cancer registry database were included. Incidence trends for 2015–2019 were extrapolated to predict incidence and stage distribution for 2020 and compared with the observed values. National healthcare reimbursement data were used to examine treatment strategies. Exact tumor diameter and nodal involvement, extracted from pathology reports, were analyzed for 2019 and 2020.Results74,975 tumors were selected for analysis of incidence and clinical stage. Invasive BC incidence declined by -5.0% in 2020, with a drop during the first COVID-19 wave (Mar-Jun; -23%) followed by a rebound (Jul-Dec; +7%). Predicted and observed incidence (in situ + invasive) was not different in patients < 50 years. In the 50–69 and 70 + age groups, significant declines of -4.1% and − 8.4% respectively were found. Excess declines were seen in clinical stage 0 and I in Mar-Jun, without excess increases in clinical stage II-IV tumors in Jul-Dec. There was no increase in average tumor diameter or nodal involvement in 2020. Patients diagnosed in Mar-Jun received significantly more neoadjuvant therapy, particularly neoadjuvant hormonal therapy for patients with clinical stage I-II BC.ConclusionsBC incidence decline in 2020 in Belgium was largely restricted to very early-stage BC and patients aged 50 and over. Delayed diagnosis did not result in an overall progression to higher stage at diagnosis in 2020. Observed treatment adaptations in Belgium were successful in prioritizing patients for surgery while preventing tumor progression in those with surgical delay. Continuation of monitoring BC incidence and stage in the future is crucial.

Abstract PO2-17-11: Management guidelines for epithelial atypia diagnosed in breast screening, based on an analysis of a large prospective cohort study (Sloane Project)

Abstract Background: Epithelial atypia in the breast is most frequently detected through breast screening. Internationally, guidelines differ between advising diagnostic surgical excision of screen-detected atypia versus vacuum-assisted excision (VAE), often with annual follow up surveillance mammography. Prospective data with detailed follow-up and outcomes for subsequent cancer events is lacking. We evaluated a large prospective cohort of screen-detected atypia (Sloane Project) and an expert consensus meeting to develop management recommendations. Methods: We undertook an observational analysis of women with screen-detected epithelial atypia (Atypical Ductal Hyperplasia (ADH), Flat Epithelial Atypia (FEA), Lobular In Situ Neoplasia (LISN), or mixed atypia) reported to the National Health Service (NHS) Breast Screening Programme (BSP) between 01/04/03 and 20/06/18. We estimated cumulative incidence of invasive cancers per 1000 women within 1 and 2 subsequent screening rounds using cumulative incidence functions and repeated these by women’s age, type of atypia and year of diagnosis. Flexible parametric modelling produced hazard ratios (HR). The results were presented at a consensus meeting with clinical experts, patient representation, national decision-makers and commissioners from the NHS in England. A consensus on management recommendations was reached. Results: Among 3238 women (19088 person-years of follow up) with screen-detected atypia, diagnoses increased from 2010 (n=119) to 2015 (n=502). This coincided with the introduction of digital mammography into English screening centres from 2010 and changes in biopsy technique. A total of 141 invasive breast cancers were detected up to December 2018. Cumulative incidence of invasive breast cancer per 1000 women with atypia (ADH, FEA, LISN or mixed) was 14.2 (95% CI 10.3, 19.1) and 45.0 (36.3, 55.1) at 3- and 6-years post atypia based on 40 and 94 cancers, respectively. Women diagnosed with atypia during 2013-2018 had an invasive cancer detected less frequently within 3 years than women with an atypia diagnosis between 2003-2007 or 2008-2012 (6.0 invasive cancers (3.1, 10.9) per 1000 women in 2013-2018 Vs 24.3 (13.7, 40.1) and 24.6 (14.9, 38.3) in 2003-2007 and 2008-2012), suggesting that atypia diagnosis may increasingly contribute to ‘overdiagnosis’. Cancers detected were similar to the general screening population regarding grade, size and nodal involvement. Ipsilateral and contralateral cancers were detected in equal numbers, supporting the concept that atypia represents a risk factor rather than precursor of invasive cancer in the short term. Results by age and type of atypia did not suggest a need for risk-stratified management. Considering subsequent invasive cancer, VAE appeared to be as safe as diagnostic surgical excision of atypia (HR 0.75 (0.45, 1.25)). The expert consensus considered that increased screening of women with screen-detected atypia over and above routine 3-yearly screening was not beneficial, given the overall low numbers of cancers at three years. This applied to all types of atypia and all women who received digital mammography and diagnosis of atypia on core or vacuum-assisted biopsy followed by VAE within a quality assured NHS BSP. Conclusions: Breast atypia represents a risk factor for invasive cancer and does not necessitate surgical excision. Changes to mammography (digital vs plain film) and biopsy techniques (gauge of needle and use of vacuum-assistance) may lead to detection of atypia which is then ‘over-managed’. Current recommendations for annual mammography for 5 years after a diagnosis of epithelial atypia may be overly cautious. We suggest that women with screen detected atypia should be followed up with routine screening appointments. Citation Format: Karoline Freeman, David Jenkinson, Karen Clements, Matthew Wallis, Sarah E Pinder, Elena Provenzano, Hilary Stobart, Nigel Stallard, Olive Kearins, Nisha Sharma, Abeer Shaaban, Cliona Kirwan, Bridget Hilton, Alastair Thompson, Sian Taylor-Phillips. Management guidelines for epithelial atypia diagnosed in breast screening, based on an analysis of a large prospective cohort study (Sloane Project) [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-17-11.

Socioeconomic Deprivation and Invasive Breast Cancer Incidence by Stage at Diagnosis: A Possible Explanation to the Breast Cancer Social Paradox.

In this study, we assessed the influence of area-based socioeconomic deprivation on the incidence of invasive breast cancer (BC) in France, according to stage at diagnosis. All women from six mainland French departments, aged 15+ years, and diagnosed with a primary invasive breast carcinoma between 2008 and 2015 were included (n = 33,298). Area-based socioeconomic deprivation was determined using the French version of the European Deprivation Index. Age-standardized incidence rates (ASIR) by socioeconomic deprivation and stage at diagnosis were compared estimating incidence rate ratios (IRRs) adjusted for age at diagnosis and rurality of residence. Compared to the most affluent areas, significantly lower IRRs were found in the most deprived areas for all-stages (0.85, 95% CI 0.81-0.89), stage I (0.77, 95% CI 0.72-0.82), and stage II (0.84, 95% CI 0.78-0.90). On the contrary, for stages III-IV, significantly higher IRRs (1.18, 95% CI 1.08-1.29) were found in the most deprived areas. These findings provide a possible explanation to similar or higher mortality rates, despite overall lower incidence rates, observed in women living in more deprived areas when compared to their affluent counterparts. Socioeconomic inequalities in access to healthcare services, including screening, could be plausible explanations for this phenomenon, underlying the need for further research.

Metformin and other anti-diabetic medication use and breast cancer incidence in the Nurses' Health Studies.

We aimed to examine the association between the use of metformin and other anti-diabetic medications and breast cancer incidence within two large prospective cohort studies. We followed 185,181 women who participated in the Nurses' Health Study (NHS; 1994-2016) and the NHSII (1995-2017), with baseline corresponding to the date metformin was approved for type 2 diabetes (T2D) treatment in the US Information on T2D diagnosis, anti-diabetes medications, and other covariates was self-reported at baseline and repeatedly assessed by follow-up questionnaires every 2 years. Breast cancer cases were self-reported and confirmed by medical record review. Hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between medication use and breast cancer were estimated using Cox proportional hazards regression models, adjusting for breast cancer risk factors. During 3,324,881 person-years of follow-up, we ascertained 9,192 incident invasive breast cancer cases, of which 451 were among women with T2D. Compared with women without T2D (n = 169,263), neither metformin use (HR = 0.97; 95% CI = 0.81-1.15) nor other anti-diabetic medications use (HR = 1.11; 95% CI = 0.90-1.36) associated with significantly lower breast cancer incidence. Among women with T2D (n = 15,918), compared with metformin never users, metformin ever use was not significantly inversely associated with breast cancer (HR = 0.92; 95% CI = 0.74-1.15). Although we observed that past use of metformin was inversely associated with breast cancer in the T2D population (HR = 0.67; 95% CI = 0.48-0.94), current use (HR = 1.01; 95% CI = 0.80-1.27) and longer duration of metformin use were not associated with breast cancer (each 2-year interval: HR = 1.01; 95% CI = 0.95-1.07). Overall, metformin use was not associated with the risk of developing breast cancer among the overall cohort population or among women with T2D.

Breast Cancer Incidence Among US Women Aged 20 to 49 Years by Race, Stage, and Hormone Receptor Status

Breast cancer in young women has a less favorable prognosis compared with older women. Yet, comprehensive data on recent trends and how period and cohort effects may affect these trends among young women are not well-known. To evaluate breast cancer incidence among young women in the US over a 20-year period by race and ethnicity, hormone receptor status (estrogen receptor [ER] and progesterone receptor [PR]), tumor stage, and age at diagnosis, as well as how period and cohort effects may affect these trends. This cross-sectional study used data from Surveillance, Epidemiology, and End Results 17 registries (2000-2019). Women aged 20 to 49 years with a primary invasive breast cancer were included. Data were analyzed between February and June 2023. Age-standardized incidence rates (ASIR), incidence rate ratios (IRR), and average annual percent changes (AAPC) stratified by race and ethnicity, hormone receptor status, tumor stage, and age at diagnosis. Out of 217 815 eligible women (1485 American Indian or Alaska Native [0.7%], 25 210 Asian or Pacific Islander [11.6%], 27 112 non-Hispanic Black [12.4%], 37 048 Hispanic [17.0%], 126 960 non-Hispanic White [58.3%]), the majority were diagnosed with an ER+/PR+ tumor (134 024 [61.5%]) and were diagnosed with a stage I tumor (81 793 [37.6%]). Overall, invasive breast cancer incidence increased (AAPC, 0.79; 95% CI, 0.42 to 1.15), with increasing trends across almost all racial and ethnic groups. ASIR increased for ER+/PR+ (AAPC, 2.72; 95% CI, 2.34 to 3.12) and ER+/PR- tumors (AAPC, 1.43; 95% CI, 1.00 to 1.87), and decreased for ER-/PR+ (AAPC, -3.25; 95% CI, -4.41 to -2.07) and ER-/PR- tumors (AAPC, -0.55; 95% CI, -1.68 to 0.60). For women aged 20 to 29 and 30 to 39 years, ASIRs were highest among non-Hispanic Black women (age 20-29 years: IRR, 1.53; 95% CI, 1.43 to 1.65; age 30-39 years: IRR, 1.15; 95% CI, 1.12 to 1.18). For women aged 40 to 49 years, ASIR was lower for non-Hispanic Black women (IRR, 0.96; 95% CI, 0.94 to 0.97) compared with non-Hispanic White women. Incidence rates increased for stages I and IV tumors but decreased for stage II and III tumors. Age-period-cohort analysis demonstrated both cohort and period effects on breast cancer incidence (P < .001). In this population-based cross-sectional analysis, an increase in breast cancer incidence rates among young US women and age-related crossover between non-Hispanic White and Black women were observed. Prevention efforts in young women need to adopt a targeted approach to address racial disparities in incidence rates observed at different age phases.

IN-SILICO CHARACTERIZATION OF HUMAN HER2 GENE TO PREDICT THE BREAST CANCER ASSOCIATED BIOMARKERS

HER2 gene hyperactivation is responsible for the incidence of invasive breast cancer (BC). It leads to over expression of HER2 receptors in breast cells resulting in abnormal receptor dimerization and signal transduction cascade initiation. It ultimately causes uncontrolled proliferation of breast cells. Therefore, this is the most susceptible target gene for BC treatment. HER2 gene transcript with accession ID ENST00000269571.10 was selected for association analysis in present study. A total of ten single nucleotide polymorphisms (SNPs) of gene were analyzed using in-silico tools like CELLO, PROTPARAM, SOPMA, and SWISSMODEL. These tools helped in determining the effect of variants on sub-cellular localization, physiochemical properties, and secondary (2D) and tertiary (3D) structures of mutated proteins. Variants rs1249755832, rs769703068, rs1567913219, and rs1213602748 altered the localization of mutated proteins. SNPs rs1213602748, rs769703068, and rs1249755832 considerably changed the isoelectric point (pI), extinction coefficient, instability index, aliphatic index, and GRAVY. Variant rs769703068 caused a change in all four properties of the 2D structure, i.e., alpha helix, extended strand, beta-turn, and random coil. Polymorphisms that caused a significant deviation in 3D configuration were rs769703068, rs144434331, and rs146177313. These variants can be recommended as biomarkers for HER2+ BC cell diagnosis.

Abstract B090: Breast cancer incidence rates by neighborhood socioeconomic status and ethnic enclaves among Asian American, Native Hawaiian, and Pacific Islander females in California

Abstract Background—Among Asian American, Native Hawaiian, and Pacific Islander (AANHPI) females in the U.S., breast cancer incidence has steadily increased1. Of note, California has the largest population of AANHPI residents in the United States2. Few studies have examined whether the incidence rates of breast cancer among AANHPI populations differ by the neighborhood social environment. Thus, we examined the incidence of invasive breast cancer by AANHPI ethnic enclave (ethnically distinct neighborhoods) and neighborhood socioeconomic status (nSES) among AANHPI females in California. Methods— With 14,738 AANHPI females diagnosed with invasive breast cancer from 2008 through 2012 from the California Cancer Registry, we calculated the incidence rates of breast cancer. The 2007 to 2011 American Community Survey (ACS) data was used to assess AANHPI ethnic enclave index and nSES at the census tract level. Incidence rate ratios (IRRs) were analyzed by statewide quintiles of AANHPI ethnic enclave index and nSES. For analyses of AANHPI ethnic enclave index and nSES combined, low and high levels were defined as quintiles 1-3 and quintiles 4-5, respectively, and IRRs were calculated for joint AANHPI and nSES as low-low, low-high, high-low, and high-high. IRR associations of ethnic enclave and nSES by stage (localized vs. advanced (regional/distant)) were also assessed. Results— Overall, neighborhoods of lower AANHPI ethnic enclave index had higher incidence rates of breast cancer for AANHPI females in California. The incidence rate of breast cancer among AANHPI living in low ethnic enclave neighborhoods were 1.16 times that of AANHPI females living high ethnic enclave neighborhoods (95% CI 1.12 to 1.20; p&amp;lt;0.001). In addition, AANHPI females living in higher SES neighborhoods had higher incidence rates of breast cancer (IRR = 1.16 comparing highest to lowest nSES quintile, 95% CI 1.12 to 1.20). The incidence rate of breast cancer among AANHPI females living in low ethnic enclave+high SES neighborhoods was 1.32 times that of AANHPI females living in high ethnic enclave+low SES neighborhoods (95% CI 1.25 to 1.39; p&amp;lt;0.001). Similar patterns of associations were observed for localized and advanced stages of the disease. Conclusion—For AANHPI females in California, incidence rates of breast cancer differed by nSES, ethnic enclave, and jointly. Impact— Future studies should examine whether the impact of these neighborhood-level factors on breast cancer incidence rates differ across specific AANHPI ethnic groups and investigate the pathways through which they contribute to breast cancer risk. Citation Format: Alya Truong, Mi-Ok Kim, Meg Mckinley, Scarlett L. Gomez, Salma Shariff-Marco, Iona Cheng. Breast cancer incidence rates by neighborhood socioeconomic status and ethnic enclaves among Asian American, Native Hawaiian, and Pacific Islander females in California [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B090.

Trajectories of body mass index in adulthood and risk of subtypes of postmenopausal breast cancer

BackgroundBody fatness is a dynamic exposure throughout life. To provide more insight into the association between body mass index (BMI) and postmenopausal breast cancer, we aimed to examine the age at onset, duration, intensity, and trajectories of body fatness in adulthood in relation to risk of breast cancer subtypes.MethodsBased on self-reported anthropometry in the prospective Norwegian Women and Cancer Study, we calculated the age at onset, duration, and intensity of overweight and obesity using linear mixed-effects models. BMI trajectories in adulthood were modeled using group-based trajectory modeling. We used Cox proportional hazards models to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for the associations between BMI exposures and breast cancer subtypes in 148,866 postmenopausal women.ResultsA total of 7223 incident invasive postmenopausal breast cancer cases occurred during follow-up. Increased overweight duration and age at the onset of overweight or obesity were associated with luminal A-like breast cancer. Significant heterogeneity was observed in the association between age at overweight and overweight duration and the intrinsic-like subtypes (pheterogeneity 0.03). Compared with women who remained at normal weight throughout adulthood, women with a descending BMI trajectory had a reduced risk of luminal A-like breast cancer (HR 0.54, 95% CI 0.33–0.90), whereas women with ascending BMI trajectories were at increased risk (HR 1.09; 95% CI 1.01–1.17 for “Normal-overweight”; HR 1.20; 95% CI 1.07–1.33 for “Normal-obesity”). Overweight duration and weighted cumulative years of overweight and obesity were inversely associated with luminal B-like breast cancer.ConclusionsIn this exploratory analysis, decreasing body fatness from obesity in adulthood was inversely associated with overall, hormone receptor-positive and luminal A-like breast cancer in postmenopausal women. This study highlights the potential health benefits of reducing weight in adulthood and the health risks associated with increasing weight throughout adult life. Moreover, our data provide evidence of intrinsic-like tumor heterogeneity with regard to age at onset and duration of overweight.

Lifestyle Factors and Energy Intakes with Risks of Breast Cancer among Pre- and Post- Menopausal Women in Taiwan.

Although the incidence of invasive breast cancer (BC) among women in Asian is generally lower than that in Western countries, the incidence of BC has been on the rise in the past three decades in Asian countries. This hospital-based case-control study aimed to explore the relationship between dietary and metabolic factors and BC risk in pre- and post-menopausal women. We enrolled 285 patients with newly diagnosed BC at the National Taiwan University Hospital and 297 controls from the local community and hospital staff. Before receiving anticancer therapy, all patients with BC and control participants completed a 57-question semi-quantitative Food Frequency Questionnaire. For pre-menopausal women, plant-based factor scores rich in seeds and nuts, soy, fruits, and seaweeds correlated significantly with reduced BC risks, whereas menarche occurring at <12 years of age, reduced physical activity, and high-density lipoprotein <40 mg/dL were associated with increased BC risks. For post-menopausal women, plant-based dietary factor scores were also associated with reduced risks, whereas increased body mass index and energy intake levels correlated with increased BC risks. Diets rich in plant-based dietary patterns are protective against BC risk, regardless of menopausal status. Habitual physical activity is protective against BC risk among pre-menopausal Taiwanese women. Maintaining optimal weight and caloric intake is beneficial for reducing post-menopausal BC risk.

Breast screening participation and degree of spread of invasive breast cancer at diagnosis in mental health service users: A population linkage study.

Women living with mental health conditions may not have shared in improvements in breast cancer screening and care. No studies have directly examined the link between reduced screening participation and breast cancer spread in women using mental health (MH) services. Population-wide linkage of a population cancer register, BreastScreen register, and mental health service data set in women aged 50 to 74 years in New South Wales, Australia, from 2008 to 2017. Incident invasive breast cancers were identified. Predictors of degree of spread (local, regional, metastatic) at diagnosis were examined using partial proportional odds regression, adjusting for age, socioeconomic status, rurality, and patterns of screening participation. A total of 29 966 incident cancers were identified and included 686 (2.4%) in women with MH service before cancer diagnoses. More than half of MH service users had regional or metastatic spread at diagnosis (adjusted odds ratio, 1.63; 95% CI, 1.41-1.89). MH service users had lower screening participation; however, advanced cancer was more common even when adjusting for screening status (adjusted odds ratio, 1.53; 95% CI, 1.32-1.77). Advanced cancer was more common in women with severe or persistent MH conditions. Low screening participation rates explain only small part of the risk of more advanced breast cancer in women who use MH services. More study is needed to understand possible mechanisms contributing to more advanced breast cancer in women living with MH conditions. Health systems need strategies to ensure that women living with MH conditions enjoy population gains in breast cancer outcomes.

Smoothing Lexis diagrams using kernel functions: A contemporary approach.

Lexis diagrams are rectangular arrays of event rates indexed by age and period. Analysis of Lexis diagrams is a cornerstone of cancer surveillance research. Typically, population-based descriptive studies analyze multiple Lexis diagrams defined by sex, tumor characteristics, race/ethnicity, geographic region, etc. Inevitably the amount of information per Lexis diminishes with increasing stratification. Several methods have been proposed to smooth observed Lexis diagrams up front to clarify salient patterns and improve summary estimates of averages, gradients, and trends. In this article, we develop a novel bivariate kernel-based smoother that incorporates two key innovations. First, for any given kernel, we calculate its singular values decomposition, and select an optimal truncation point-the number of leading singular vectors to retain-based on the bias-corrected Akaike information criterion. Second, we model-average over a panel of candidate kernels with diverse shapes and bandwidths. The truncated model averaging approach is fast, automatic, has excellent performance, and provides a variance-covariance matrix that takes model selection into account. We present an in-depth case study (invasive estrogen receptor-negative breast cancer incidence among non-Hispanic white women in the United States) and simulate operating characteristics for 20 representative cancers. The truncated model averaging approach consistently outperforms any fixed kernel. Our results support the routine use of the truncated model averaging approach in descriptive studies of cancer.

The association between the incidence of postmenopausal breast cancer and occupational exposure to selected organic solvents, Montreal, Canada, 2008-2011.

Breast cancer is the most diagnosed cancer among women and recognized risk factors explain 25%-47% of cases. Organic solvents are used widely in the workplace and exposure may increase the risk of developing breast cancer, yet there are insufficient data to confirm this hypothesis. We sought to determine whether past occupational exposures to selected organic solvents were associated with the incidence of invasive breast cancer in postmenopausal women in Montréal, Canada. From a population-based case-control study (2008-2011), using in-depth interviews we elicited information on risk factors and lifetime occupational histories. Industrial hygienists and chemists translated job descriptions into specific chemical and physical exposures. We assessed 11 individual solvents and four solvent groups. Unconditional logistic regression was used to estimate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for metrics of past exposures to selected solvents. Exposure metrics included any previous exposure, average frequency in hours per week, duration in years, and average cumulative concentration weighted by hours per workweek exposed. We enrolled 695 cases and 608 controls. We found increased ORs for average cumulative concentration of exposure to mononuclear aromatic hydrocarbons (OR: 1.52, 95%CI: 1.04, 2.28), chlorinated alkanes (OR: 2.42, 95%CI: 1.23, 5.68), toluene (OR: 1.59, 95%CI: 1.02, 2.59), and a group of organic solvents with reactive metabolites (OR: 1.53, 95%CI: 1.08, 2.24). Positive associations were found across all exposure metrics and were higher among women with estrogen-positive/progesterone-negative tumors. Our findings suggest occupational exposure to certain organic solvents may increase the risk of incident postmenopausal breast cancer.

Combined and progestagen-only hormonal contraceptives and breast cancer risk: A UK nested case-control study and meta-analysis.

Current or recent use of combined oral contraceptives (containing oestrogen+progestagen) has been associated with a small increase in breast cancer risk. Progestagen-only contraceptive use is increasing, but information on associated risks is limited. We aimed to assess breast cancer risk associated with current or recent use of different types of hormonal contraceptives in premenopausal women, with particular emphasis on progestagen-only preparations. Hormonal contraceptive prescriptions recorded prospectively in a UK primary care database (Clinical Practice Research Datalink [CPRD]) were compared in a nested case-control study for 9,498 women aged <50 years with incident invasive breast cancer diagnosed in 1996 to 2017, and for 18,171 closely matched controls. On average, 7.3 (standard deviation [SD] 4.6) years of clinical records were available for each case and their matched controls prior to the date of diagnosis. Conditional logistic regression yielded odds ratios (ORs) and 95% confidence intervals (CIs) of breast cancer by the hormonal contraceptive type last prescribed, controlled for age, GP practice, body mass index, number of recorded births, time since last birth, and alcohol intake. MEDLINE and Embase were searched for observational studies published between 01 January 1995 and 01 November 2022 that reported on the association between current or recent progestagen-only contraceptive use and breast cancer risk in premenopausal women. Fixed effects meta-analyses combined the CPRD results with previously published results from 12 observational studies for progestagen-only preparations. Overall, 44% (4,195/9,498) of women with breast cancer and 39% (7,092/18,171) of matched controls had a hormonal contraceptive prescription an average of 3.1 (SD 3.7) years before breast cancer diagnosis (or equivalent date for controls). About half the prescriptions were for progestagen-only preparations. Breast cancer ORs were similarly and significantly raised if the last hormonal contraceptive prescription was for oral combined, oral progestagen-only, injected progestagen, or progestagen-releasing intrauterine devices (IUDs): ORs = 1.23 (95% CI [1.14 to 1.32]; p < 0.001), 1.26 (95% CI [1.16 to 1.37]; p < 0.001), 1.25 (95% CI [1.07 to 1.45]; p = 0.004), and 1.32 (95% CI [1.17 to 1.49]; p < 0.001), respectively. Our meta-analyses yielded significantly raised relative risks (RRs) for current or recent use of progestagen-only contraceptives: oral = 1.29 (95% CI [1.21 to 1.37]; heterogeneity χ25 = 6.7; p = 0.2), injected = 1.18 (95% CI [1.07 to 1.30]; heterogeneity χ28 = 22.5; p = 0.004), implanted = 1.28 (95% CI [1.08 to 1.51]; heterogeneity χ23 = 7.3; p = 0.06), and IUDs = 1.21 (95% CI [1.14 to 1.28]; heterogeneity χ24 = 7.9; p = 0.1). When the CPRD results were combined with those from previous published findings (which included women from a wider age range), the resulting 15-year absolute excess risk associated with 5 years use of oral combined or progestagen-only contraceptives in high-income countries was estimated at: 8 per 100,000 users from age 16 to 20 years and 265 per 100,000 users from age 35 to 39 years. The main limitation of the study design was that, due to the nature of the CPRD data and most other prescription databases, information on contraceptive use was recorded during a defined period only, with information before entry into the database generally being unavailable. This means that although our findings provide evidence about the short-term associations between hormonal contraceptives and breast cancer risk, they do not provide information regarding longer-term associations, or the impact of total duration of contraceptive use on breast cancer risk. This study provides important new evidence that current or recent use of progestagen-only contraceptives is associated with a slight increase in breast cancer risk, which does not appear to vary by mode of delivery, and is similar in magnitude to that associated with combined hormonal contraceptives. Given that the underlying risk of breast cancer increases with advancing age, the absolute excess risk associated with use of either type of oral contraceptive is estimated to be smaller in women who use it at younger rather than at older ages. Such risks need be balanced against the benefits of using contraceptives during the childbearing years.

Randomized Placebo Controlled Trial of Low-Dose Tamoxifen to Prevent Recurrence in Breast Noninvasive Neoplasia: A 10-Year Follow-Up of TAM-01 Study.

Five-year data of the phase III trial TAM-01 showed that low-dose tamoxifen at 5 mg once daily administered for 3 years in women with intraepithelial neoplasia (IEN) reduced by 52% the recurrence of invasive breast cancer or ductal carcinoma in situ (DCIS), without additional adverse events over placebo. Here, we present the 10-year results. We randomly assigned 500 women with breast IEN (atypical ductal hyperplasia, lobular carcinoma in situ [LCIS], or hormone-sensitive or unknown DCIS) to low-dose tamoxifen or placebo after surgery with or without irradiation. The primary end point was the incidence of invasive breast cancer or DCIS. The TAM-01 population included 500 women (20% atypical ductal hyperplasia, 11% LCIS, and 69% DCIS). The mean (±SD) age at the start of treatment was 54 ± 9 years, and 58% of participants were postmenopausal. After a median follow-up of 9.7 years (IQR, 8.3-10.9 years), 66 breast cancers (15 in situ; 51 invasive) were diagnosed: 25 in the tamoxifen group and 41 in the placebo group (annual rate per 1,000 person-years, 11.3 with tamoxifen v 19.5 with placebo; hazard ratio [HR], 0.58; 95% CI, 0.35 to 0.95; log-rank P = .03). Most recurrences were invasive (77%) and ipsilateral (59%). Regarding contralateral breast cancer incidence, there were six events in the tamoxifen arm and 16 in the placebo arm (HR, 0.36; 95% CI, 0.14 to 0.92; P = .025). The number needed to be treated to prevent one case of breast event with tamoxifen therapy was 22 in 5 years and 14 in 10 years. The benefit was seen across all patient subgroups. There was a significant 50% reduction of recurrence with tamoxifen in the DCIS cohort, which represents 70% of the overall population (HR, 0.50; 95% CI, 0.28 to 0.91; P = .02). No between-group difference in the incidence of serious adverse events was reported during the prolonged follow-up period. Tamoxifen 5 mg once daily for 3 years significantly prevents recurrence from noninvasive breast cancer after 7 years from treatment cessation without long-term adverse events.

Abstract GS4-08: 10-year results of a phase 3 trial of low-dose tamoxifen in non-invasive breast cancer

Abstract We have previously shown in a phase 3 trial that tamoxifen 5 mg/day for 3 years decreased by 52% the incidence of recurrence of invasive breast cancer or DCIS after a median follow-up of 5.1 years in women with excised non invasive breast disease, including atypical ductal hyperplasia, DCIS or LCIS (DeCensi et al. JCO 2019; 37:1629). Toxicity was negligible with only an extra hot flash per day in the tamoxifen arm compared with the placebo arm. These findings were incorporated into the ASCO clinical practice guidelines for breast cancer risk reduction as an alternative option to standard doses and duration of tamoxifen or aromatase inhibitors in women with non-invasive disease (Visvanathan et al. JCO 2019; 37:3152). In the present study we update the findings on breast cancer recurrence after a median of 9.14 years (interquartile range, IQR, 7.16-10.73) and a total of 10.57 person years of follow up to see if the treatment effect is retained with more events and after a median of approximately 6 years from treatment cessation. We conducted a national multicenter randomized trial of tamoxifen, 5 mg/d or placebo administered for 3 years after surgery in women with hormone-sensitive or unknown breast intraepithelial neoplasia, including atypical ductal hyperplasia and lobular or ductal carcinoma in situ. The primary end point was the incidence of invasive breast cancer or ductal carcinoma in situ. Between November 1, 2008, and March 31, 2015, 1,160 women were screened and 500 aged 75 years of age or younger were included in the study. Women with high-grade or comedo/necrotic DCIS received adjuvant radiotherapy of 50 Gy in 25 courses. The mean age was 54 years (standard deviation, 9 years), and 55% of participants were postmenopausal. The mean (SD) body mass index, kg/m2, was 25.7 (4.8) on tamoxifen and 25.3 (4.2) on placebo. Twenty percent had ADH, 11% had LCIS, and the remaining 69% had DCIS. After a median follow-up of 9.14 years, there were 22 neoplastic events (invasive breast cancer or DCIS) with tamoxifen and 37 with placebo (annual rate 11.09, 95% CI, 7-30-16.84 on T vs 19.71, 95% CI, 14.28-27.21 on P per 1,000 person-years; hazard ratio, 0.56; 95% CI, 0.33 to 0.95; P = .03), which resulted in a 5-year number needed to treat of 18. Overall, 71% of the recurrences were invasive breast cancer. The follow-up was updated with the most recent visit within 12 months in two thirds of the participants, so an update of all participants will be performed by Sept 30th with full analysis of neoplastic events, annual risk rate ratio, serious adverse events and deaths. Moreover, an updated analysis of potential effect modifiers will be conducted, including menopausal status, baseline estradiol levels, menopausal symptoms, BMI, smoking status and Ki-67 of the primary lesion. In conclusion, our findings indicate that low dose tamoxifen given for 3 years still significantly prevents recurrences from non-invasive breast cancer after a median of 6 years from treatment cessation, providing a valid prevention/interception option in this disease group. Supported by Ente Ospedaliero Ospedali Galliera, Genova, Italy, the Italian Ministry of Health (RFPS-2006-1-339898), the Italian Association for Cancer Research (IG 2008 Grant No. 5611), and the Italian League against Cancer (LILT 7-08). Citation Format: Andrea De Censi, Matteo Lazzeroni, Matteo Puntoni, Luca Boni, Aliana Guerrieri Gonzaga, Tania Buttiron Webber, Marianna Fava, Irene Maria Briata, Livia Giordano, Maria Digennaro, Laura Cortesi, Fabio Falcini, Franca Avino, Francesco Millo, Katia Cagossi, Elisa Gallerani, Alessia De Simone, Anna Cariello, Giuseppe Aprile, Maria Renne, Bernardo Bonanni. 10-year results of a phase 3 trial of low-dose tamoxifen in non-invasive breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr GS4-08.

Abstract PD12-02: PD12-02 Obesity is associated with poor breast cancer prognosis, particularly among women with low socioeconomic position

Abstract Purpose: To examine the association between obesity and breast cancer outcomes and to describe socioeconomic position (SEP) in patients enrolled in the Malmö Diet and Cancer Study (MDCS) according to anthropometric measures. Patients and methods: The MDCS is a prospective cohort study that enrolled 17,035 female individuals in Malmö, Sweden from 1991 to 1996. The primary objective of the MDCS was to investigate associations between dietary patterns and cancer risk. Body mass index (BMI) and waist circumferences were measured upon enrollment, in the MDCS cohort. We identified all female MDCS participants with incident invasive breast cancer diagnosed between 1991 and 2014. The primary endpoint was breast cancer recurrence, defined as the time from breast cancer diagnosis until the earliest occurrence of invasive loco-regional recurrence or distant metastases. Follow-up time began at breast cancer diagnosis and continued until the first of breast cancer recurrence, death, emigration, or end of follow-up (June 8, 2020). BMI and waist circumference were categorized according to the World Health Organization guidelines as healthy weight (18.5-24.9 kg/m2 or waist &amp;lt; 81 cm), overweight (25.0-29.9 kg/m2 or waist 81-85 cm), and obese (≥ 30.0 kg/m2 or waist &amp;gt; 85 cm). Consistent with the Swedish socioeconomic classification, we categorized labor status into two groups—manual labor and non-manual labor. We categorized socioeconomic position (SEP) as low if patients had unskilled manual labor with &amp;lt; 2 years post-high school education, low-middle if skilled manual labor with &amp;gt; 2 years of post-high school education, high-middle if assistant non-manual labor with &amp;lt; 3 years of post-high school education, and high if non-manual labor with &amp;gt; 3 years of post-high school education. We fit Cox regression models to compute crude and adjusted hazard ratios (HRs) with 95% confidence intervals (95% CI) of breast cancer recurrence as well as all-cause mortality according to BMI and waist circumference. To evaluate effect measure modification, we stratified the Cox models by labor status, SEP, and smoking. Results: Among 1,099 breast cancer patients, 263 breast cancer recurrences were diagnosed over 12,810 person-years with a median follow-up of 11.1 years (interquartile range [IQR] was 6.6-16.2). The cohort consisted of 556 patients with healthy weight, 384 patients with overweight, and 159 patients with obesity. The median age at breast cancer diagnosis was 66.3 years (IQR: 61.2-72.8), and patients with obesity were older than patients with healthy weight (69.2 vs 64.9 years). In multivariable analyses, having obesity according to BMI was associated with increased rate of recurrence (HR= 1.44 [95% CI: 1.00-2.07]) and all-cause mortality (HR= 1.50 [95% CI: 1.13-1.98]) in comparison to having healthy weight. Similarly, having obesity according to waist circumference was associated with higher risk of recurrence (HR= 1.31 [95% CI: 0.98-1.77]) and all-cause mortality (HR= 1.72 [95% CI: 1.39-2.13]) in comparison to having healthy weight. When evaluating effect measure modification, we observed that obesity was associated with breast cancer recurrence in obese non-smoking women (HR= 1.66 [95% CI: 1.01-2.73]), in obese women with manual labor (HR= 2.45 [95% CI: 1.22-4.93]), and obese women with low SEP (HR= 2.55 [95% CI: 1.08-6.02]). We observed little evidence of an association between obesity and breast cancer recurrence among smokers (HR= 1.12 [95% CI: 0.43-2.92]), among patients with non-manual labor (HR= 0.94 [95% CI: 0.44-2.00]), or among patients with high SEP (HR= 1.47 [95% CI: 0.58-3.75]). Conclusion: Obesity defined by pre-diagnostic levels of BMI and waist circumference was associated with an increased risk of recurrence and all-cause mortality among breast cancer patients. The association between obesity and breast cancer recurrence seems dependent on patient characteristics such as labor status, socioeconomic position, and smoking. Citation Format: Sixten Harborg, Maria Feldt, Deirdre Cronin-Fenton, Susanne Dalton, Ann Rosendahl, Signe Borgquist. PD12-02 Obesity is associated with poor breast cancer prognosis, particularly among women with low socioeconomic position [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD12-02.

Clinical Outcomes of Conservative Treatment for Low-Risk Ductal Carcinoma in Situ: A Systematic Review and Pooled Analysis

AimsThe current gold standard of treatment for ductal carcinoma in situ (DCIS) is surgical resection with or without adjuvant radiotherapy. However, the increased detection and radical treatment of DCIS did not result in a declined incidence of invasive breast cancers, leading to the debate if DCIS has been overtreated. While ongoing randomised controlled trials on active surveillance of DCIS are still in progress, this systematic review aims to evaluate the best evidence on conservative treatment for DCIS from the literature. Materials and methodsThis systematic review was conducted in line with the PRISMA statement. We included all relevant studies published up to June 2022 for analysis. The primary outcomes were overall survival and breast cancer-specific survival (BCSS) of conservative treatment for DCIS. ResultsThree studies, with a total of 34 007 women with low-risk DCIS, were included in the analysis. Active and conservative treatments both resulted in excellent 10-year BCSS, with no statistically insignificant difference (98.6% versus 96.0%, 31 478 women). One study comparing 5-year BCSS of active and conservative treatments only in subjects aged over 80 years also reported [AQ1]an insignificant difference (98.2% versus 96.0%, 2529 women). One study measuring 5- and 10-year overall survival between the treatment groups also reported [AQ1]an insignificant difference (5-year: 96.2% versus 92.4%; 10-year: 85.6% versus 86.7%, 31 106 women). ConclusionBCSS between active and conservative treatment for women with low-risk DCIS is both excellent and comparable, suggesting that conservative treatment is a possible alternative without compromising survival.