Breast Cancer Disparities at Home and Abroad: A Review of the Challenges and Opportunities for System-Level Change

Race, Gene Expression Signatures, and Clinical Outcomes of Patients With High-Risk Early Breast Cancer

Importance

There has been little consideration of genomic risk of recurrence by breast cancer subtype despite evidence of racial disparities in breast cancer outcomes.

Objective

To evaluate associations between clinical trial end points, namely pathologic complete response (pCR) and distant recurrence-free survival (DRFS), and race and examine whether gene expression signatures are associated with outcomes by race.

Design, Setting, and Participants

This retrospective cohort study used data from the Investigation of Serial Studies to Predict Your Therapeutic Response With Imaging and Molecular Analysis 2 (I-SPY 2) multicenter clinical trial of neoadjuvant chemotherapy with novel agents and combinations for patients with previously untreated stage II/III breast cancer. Analyses were conducted of associations between race and short- and long-term outcomes, overall and by receptor subtypes, and their association with 28 expression biomarkers. The trial enrolled 990 female patients between March 30, 2010, and November 5, 2016, with a primary tumor size of 2.5 cm or greater and clinical or molecular high risk based on MammaPrint or hormone receptor (HR)-negative/ERBB2 (formerly HER2 or HER2/neu)-positive subtyping across 9 arms. This data analysis was performed between June 10, 2021, and October 20, 2022.

Exposure

Race, tumor receptor subtypes, and genomic biomarker expression of early breast cancer.

Main Outcomes and Measures

The primary outcomes were pCR and DRFS assessed by race, overall, and by tumor subtype using logistic regression and Cox proportional hazards regression models. The interaction between 28 expression biomarkers and race, considering pCR and DRFS overall and within subtypes, was also evaluated.

Results

The analytic sample included 974 participants (excluding 16 self-reporting as American Indian or Alaska Native, Native Hawaiian or Other Pacific Islander, or multiple races due to small sample sizes), including 68 Asian (7%), 120 Black (12%), and 786 White (81%) patients. Median (range) age at diagnosis was 47 (25-71) years for Asian, 49 (25-77) for Black, and 49 (23-73) years for White patients. The pCR rates were 32% (n = 22) for Asian, 30% for Black (n = 36), and 32% for White (n = 255) patients (P = .87). Black patients with HR-positive/ERBB2-negative tumors not achieving pCR had significantly worse DRFS than their White counterparts (hazard ratio, 2.28; 95% CI, 1.24-4.21; P = .01), with 5-year DRFS rates of 55% (n = 32) and 77% (n = 247), respectively. Black patients with HR-positive/ERBB2-negative tumors, compared with White patients, had higher expression of an interferon signature (mean [SD], 0.39 [0.87] and -0.10 [0.99]; P = .007) and, compared with Asian patients, had a higher mitotic score (mean [SD], 0.07 [1.08] and -0.69 [1.06]; P = .01) and lower estrogen receptor/progesterone receptor signature (mean [SD], 0.31 [0.90] and 1.08 [0.95]; P = .008). A transforming growth factor β signature had a significant association with race relative to pCR and DRFS, with a higher signature associated with lower pCR and worse DRFS outcomes among Black patients only.

Conclusions and Relevance

The findings show that women with early high-risk breast cancer who achieve pCR have similarly good outcomes regardless of race, but Black women with HR-positive/ERBB2-negative tumors without pCR may have worse DRFS than White women, highlighting the need to develop and test novel biomarker-informed therapies in diverse populations.

Race and Ethnicity Reporting and Enrollment Disparities in Clinical Trials Leading to FDA Approvals for Breast Cancer Between 2010 and 2020

BACKGROUND

We determined the race and ethnicity demographics and reporting trends of clinical trials leading to Food and Drug Administration (FDA) approvals for breast cancer.

METHODS

We collected enrollment and reporting data from clinical trials leading to FDA novel and new use approvals for breast cancer from 2010 to 2020 from Drugs@FDA, ClinicalTrials.gov, and associated journal manuscripts. Enrollment demographics were compared to the US cancer population estimates obtained using National Cancer Institute-Surveillance, Epidemiology, and End Results and 2010 US Census databases.

RESULTS

Seventeen drugs received approval based on 18 clinical trials with a total enrollment of 12,334. For approvals from 2010 to 2015 and from 2016 to 2020, there was no significant difference in race (80% vs. 91.6%, P = .34) or ethnicity reporting (20% vs. 33.3%, P = .5) on ClinicalTrials.Gov, manuscripts, and FDA labels. For trials that reported race and ethnicity, White, Asian, Black, and Hispanic patients represented 73.8%, 16.4%, 3.7%, and 10.4% of trial participants. Relative to their US cancer incidence, Black (31% of expected) patients were underrepresented compared with White (90% of expected), Hispanic (115%), and Asian (327% of expected) patients.

CONCLUSION

We observed no significant difference in race and ethnicity reporting in pivotal clinical trials leading to FDA approval for breast cancer from 2010 to 2020. Black patients were underrepresented in these pivotal trials relative to White, Hispanic, and Asian patients. Ethnicity reporting remained low throughout the study period. Innovative approaches are needed to ensure equitable benefit of novel therapeutics.

Lower breast cancer survival among Black women in Brazil: a population-based retrospective study

OBJECTIVES

To analyze the rates of breast cancer survival among Black and White women according to age and stage at diagnosis.

STUDY DESIGN

A retrospective cohort study.

METHODS

The study examined women registered in the population-based cancer registry of Campinas in 2010-2014. The primary variable was the declared race (White or Black). Other races were excluded. Data were linked with the Mortality Information System, and missing information was accessed by active search. Overall survival (OS) was calculated by the Kaplan-Meier method, comparisons were done by chi-squared tests, and hazard ratios were examined by Cox regression.

RESULTS

The total numbers of new cases of staged breast cancer among Black and White women were 218 and 1522 cases, respectively. The rates of stages III/IV were 35.5% among White women and 43.1% among Black women (P = 0.024). The frequencies among White and Black women under 40 years old were 8.0% and 12.4% (P = 0.031), 19.6% and 26.6% (P = 0.016) for ages of 40-49 years, and 23.8% and 17.4% (P = 0.037) for ages of 60-69 years, respectively. The mean OS was 7.5 years (7.0; 8.0) among Black women and 8.4 years (8.2; 8.5) among White women. The 5-year OS was 72.3% among Black women and 80.5% among White women (P = 0.001). Black women had an age-adjusted risk of death that was 1.7 times higher (1.33; 2.20). The risk was 6.4 times higher for diagnoses in stage 0 (1.65; 24.90) and 1.5 times for diagnoses in stage IV (1.04; 2.17).

CONCLUSION

The 5-year OS for women with breast cancer was significantly lower among Black women than White women. Black women were more frequently diagnosed in stages III/IV, and their age-adjusted risk of death was 1.7 times higher. Differences in access to care may explain these differences.

Achieving equitable access to cancer screening services to reduce the cancer burden in the Asia-Pacific region: Experience from Hong Kong

The global burden of cancer can be reduced through early detection by providing people with unrestricted access to cancer screening services. However, health disparities exist within and across countries and regions. This viewpoint article uses the Integrative Multicomponent Programme for Promoting South Asians' Cancer Screening Uptake (IMPACT) project as an example of sharing strategies, such as evidence-based multimedia interventions, community health worker-led interventions, strengthening relationships and building networks, that are being adopted to improve ethnic minorities' access to cancer screening services in Hong Kong. We find that the IMPACT project effectively increased South Asians' cancer screening uptake (e.g. the cervical cancer screening uptake rate saw a 42% increase over 5 years). Future directions for scaling up the IMPACT project have been suggested to contribute to achieving Goal 3 in the United Nations Sustainable Development Goals by 2030, that is, ensuring healthy lives and promoting the well-being of all people at all ages.

Economic Perspective of Cancer Care and Its Consequences for Vulnerable Groups

Simple Summary

For cancer patients, many different reasons can cause financial burdens and economic threads. Sociodemographic factors, rural/remote location and income are known determinants for these vulnerable groups. This economic vulnerability is related to the reduced utilization of cancer care and the impact on outcome. Financial burden has been reported in many countries throughout the world and needs to be addressed as part of the sufficient quality of cancer care.

Abstract

Within healthcare systems in all countries, vulnerable groups of patients can be identified and are characterized by the reduced utilization of available healthcare. Many different reasons can be attributed to this observation, summarized as implementation barriers involving acceptance, accessibility, affordability, acceptability and quality of care. For many patients, cancer care is specifically associated with the occurrence of vulnerability due to the complex disease, very different target groups and delivery situations (from prevention to palliative care) as well as cost-intensive care. Sociodemographic factors, such as educational level, rural/remote location and income, are known determinants for these vulnerable groups. However, different forms of financial burdens likely influence this vulnerability in cancer care delivery in a distinct manner. In a narrative review, these socioeconomic challenges are summarized regarding their occurrence and consequences to current cancer care. Overall, besides direct costs such as for treatment, many facets of indirect costs including survivorship costs for the cancer patients and their social environment need to be considered regarding the impact on vulnerability, treatment compliance and abundance. In addition, individual cancer-related financial burden might also affect the society due to the loss of productivity and workforce availability. Healthcare providers are requested to address this vulnerability during the treatment of cancer patients.

Gene-Level Germline Contributions to Clinical Risk of Recurrence Scores in Black and White Patients with Breast Cancer

Continuous risk of recurrence scores (CRS) based on tumor gene expression are vital prognostic tools for breast cancer. Studies have shown that Black women (BW) have higher CRS than White women (WW). Although systemic injustices contribute substantially to breast cancer disparities, evidence of biological and germline contributions is emerging. In this study, we investigated germline genetic associations with CRS and CRS disparity using approaches modeled after transcriptome-wide association studies (TWAS). In the Carolina Breast Cancer Study, using race-specific predictive models of tumor expression from germline genetics, we performed race-stratified (N = 1,043 WW, 1,083 BW) linear regressions of three CRS (ROR-S: PAM50 subtype score; proliferation score; ROR-P: ROR-S plus proliferation score) on imputed tumor genetically regulated tumor expression (GReX). Bayesian multivariate regression and adaptive shrinkage tested GReX-prioritized genes for associations with tumor PAM50 expression and subtype to elucidate patterns of germline regulation underlying GReX-CRS associations. At FDR-adjusted P < 0.10, 7 and 1 GReX prioritized genes among WW and BW, respectively. Among WW, CRS were positively associated with MCM10, FAM64A, CCNB2, and MMP1 GReX and negatively associated with VAV3, PCSK6, and GNG11 GReX. Among BW, higher MMP1 GReX predicted lower proliferation score and ROR-P. GReX-prioritized gene and PAM50 tumor expression associations highlighted potential mechanisms for GReX-prioritized gene to CRS associations. Among patients with breast cancer, differential germline associations with CRS were found by race, underscoring the need for larger, diverse datasets in molecular studies of breast cancer. These findings also suggest possible germline trans-regulation of PAM50 tumor expression, with potential implications for CRS interpretation in clinical settings. SIGNIFICANCE: This study identifies race-specific genetic associations with breast cancer risk of recurrence scores and suggests mediation of these associations by PAM50 subtype and expression, with implications for clinical interpretation of these scores.

Race disparities in mortality by breast cancer from 2000 to 2017 in São Paulo, Brazil: a population-based retrospective study

Background

In Brazil, inequalities in access may interfere with cancer care. This study aimed to evaluate the influence of race on breast cancer mortality in the state of São Paulo, from 2000 to 2017, contextualizing with other causes of death.

Methods

A population-based retrospective study using mortality rates, age and race as variables. Information on deaths was collected from the Ministry of Health Information System. Only white and black categories were used. Mortality rates were age-adjusted by the standard method. For statistical analysis, linear regression was carried out.

Results

There were 60,940 deaths registered as breast cancer deaths, 46,365 in white and 10,588 in black women. The mortality rates for 100,000 women in 2017 were 16.46 in white and 9.57 in black women, a trend to reduction in white (p = 0.002), and to increase in black women (p = 0.010). This effect was more significant for white women (p < 0.001). The trend to reduction was consistent in all age groups in white women, and the trend to increase was observed only in the 40–49 years group in black women. For ‘all-cancer causes’, the trend was to a reduction in white (p = 0.031) and to increase in black women (p < 0.001). For ‘ill-defined causes’ and ‘external causes’, the trend was to reduce both races (p < 0.001).

Conclusion

The declared race influenced mortality rates due to breast cancer in São Paulo. The divergences observed between white and black women also were evident in all cancer causes of death, which may indicate inequities in access to highly complex health care in our setting.

Hormone receptor-positive breast cancer and black race: does sex matter?

PURPOSE

Black breast cancer patients have worse clinical outcomes than their White counterparts. There are few studies comparing clinical outcomes between Black male breast cancer (MBC) and female breast cancer (FBC) patients. The objective of this study is to examine differences in presentation, treatment, and mortality between Black MBC and FBC.

METHODS

The National Cancer Database was queried for all Black MBC and FBC patients, ages 18-90, with hormone receptor-positive breast cancer diagnosed between 2010 and 2016. Hormone receptor positivity was defined as estrogen receptor-positive, progesterone-positive and HER 2-negative cancer. Sociodemographic and clinical variables were compared between MBC and FBC patients on bivariable analysis. After propensity score matching, overall survival was evaluated using the log-rank test and Cox proportional hazards.

RESULTS

Compared to FBC patients, MBC patients had higher rates of metastatic disease (stage 4, MBC 4.4% vs. FBC 2.6%, p < 0.001), larger tumors (tumor size < 2 cm, MBC 32.1 vs. FBC 49.1%, p < 0.001) and a higher percentage of poorly differentiated tumors (grade 3, MBC 28.5% vs. FBC 21.4%, p < 0.001). MBC patients had lower rates of hormone therapy (MBC 66.4% vs. FBC 80.7%, p < 0.001) and neoadjuvant chemotherapy (MBC 5.8% vs. FBC 7.5%, p = 0.05) than FBC. On propensity score matched analysis, Black MBC patients had a higher overall mortality (p25 of 60 months vs. 74 months) compared to FBC patients (p = 0.0260).

CONCLUSION

Among hormone receptor-positive Black MBC and FBC patients, there are sex-based disparities in stage, hormone therapy use and overall survival.

Socioeconomic and Racial Disparities in Cancer Stage at Diagnosis, Tumor Size, and Clinical Outcomes in a Large Cohort of Women with Breast Cancer, 2007-2016

BACKGROUND

Socioeconomic and treatment factors contribute to diagnosis of early-stage (local-stage) breast cancer, as well as excess deaths among African American women.

OBJECTIVES

We evaluated socioeconomic and treatment predictive factors for early-stage breast cancer among African American women compared to Caucasian women. A secondary aim evaluated predictors and overall risks associated with all-cause and breast cancer-specific mortality.

METHODS

We used retrospective cohort population-based study data from the Surveillance, Epidemiology, and End Results (SEER) Program on 547,703 women aged ≥ 20 years diagnosed with breast cancer primary tumors from 2007 to 2016. Statistical analysis used logistic regression to assess predictors of early-stage breast cancer and Cox proportional hazards regression for mortality risks.

RESULTS

African American women were more likely to be diagnosed at advanced-stage, had larger tumor size at diagnosis, and received less cancer-directed surgery, but more chemotherapy than Caucasian women. Insured women (> 50%) were more likely to be diagnosed at early-stage and to have smaller tumors (p < 0.05). Education level, poverty level, and household income had no impact on racial disparities or socioeconomic disparities in women diagnosed at early stage. We found increased risks for all-cause mortality (hazard ratio = 1.18; 95% confidence interval, 1.16-1.21) and breast cancer-specific mortality (HR = 1.22; 95% CI, 1.19-1.25) among African American women compared to Caucasian women after adjusting for demographic, socioeconomic, and treatment factors.

CONCLUSIONS

In this population-based study using the most recent SEER data, African American women with breast cancer continued to exhibit higher all-cause mortality and breast cancer-specific mortality compared to Caucasian women.

Retrospective cohort analysis of prescription patterns of cancer medications during periods of drug stockouts in Botswana

OBJECTIVE

Cancer drug stockouts occur at high frequencies globally, however, their effects on treatment are understudied in sub-Saharan Africa (SSA). We aimed to determine whether causes of suboptimal cancer treatment prescriptions differed between periods of stockout and full treatment supply.

DESIGN

A retrospective cohort study of systemic therapy prescriptions for patients diagnosed with the twelve most common solid tumour cancers treated in 2016.

SETTING

Princess Marina Hospital in Gaborone, Botswana.

PARTICIPANTS

Patients in the retrospective cohort who experienced any suboptimal treatment events, defined as ≥7 days delay or switch from guideline-concordant initiated therapy.

PRIMARY AND SECONDARY OUTCOME MEASURES

Frequency of delays and patterns of prescription changes for specific regimens and cancer types.

RESULTS

167/378 patients contributed to 320 suboptimal events (115 therapy switches, 167 delays and 38 events with both), over 1452 total chemotherapy cycles received. Events during stockout were 43% delays, 43% switches and 14% both during stockout periods and 67.2% delays, 24.4% switches and 8.4% both during non-stockout periods (p<0.001). Majority of switches involved de-escalation of initially prescribed guideline-recommended regimens in patients with breast cancer, Kaposi sarcoma and patients with colorectal cancer, which occurred more frequently during periods of drug stockouts. Among patients with breast cancer, substitution of docetaxel for paclitaxel event occurred exclusively during paclitaxel drug stockout. Delays of ≥7 days events were most frequent in breast cancer patients receiving paclitaxel during stockout, and combination doxorubicin and cyclophosphamide even during periods of non-stockout.

CONCLUSIONS

The aetiology of suboptimal events differed during stockout and non-stockout periods. Prescription patterns that involved de-escalation of initiated therapy and substitution of paclitaxel with docetaxel occurred frequently during periods of drug stockout. Further research needs to be conducted to understand the impact of stockout on survival and barriers to maintaining essential cancer medicines supplies in SSA, and the factors driving frequent delays in therapy delivery.

Addressing disparities and challenges in underserved patient populations with metastatic breast cancer in Europe

People with metastatic breast cancer face many challenges and disparities in obtaining optimal cancer care. These challenges are accentuated in underserved patient populations across Europe, who are less likely to receive quality healthcare for reasons including socioeconomic inequalities, educational or cultural status, or geographic location. While there are many local and national initiatives targeted to address these challenges, there remains a need to reduce disparities and improve access to healthcare to improve outcomes, with a focus on multidisciplinary stakeholder engagement. In October 2019, a range of experts in metastatic breast cancer, including healthcare professionals, patient representatives, policymakers and politicians, met to discuss and prioritize the critical needs of underserved patient populations with metastatic breast cancer in Europe. Six key challenges faced by these communities were identified: the need for amplification of the metastatic breast cancer patient voice, better and wider implementation of high-quality guidelines for metastatic breast cancer, more collaboration between stakeholders, tailored support for patients from different cultural and ethnic backgrounds, improved data sharing, and work-related issues. The Expert Panel then conceived and discussed potential actionable goals to address each key challenge. Their conclusions present a set of interrelated approaches to address the different challenges and could serve as the basis for concerted improvement of the lives of patients with metastatic breast cancer in Europe.

Association of Insurance Status and Racial Disparities With the Detection of Early-Stage Breast Cancer

Importance

Compared with non-Hispanic white women, racial/ethnic minority women receive a diagnosis of breast cancer at a more advanced stage and have higher morbidity and mortality with breast cancer diagnosis. Access to care with adequate insurance may be associated with earlier diagnosis, expedited treatment, and improved prognosis.

Objective

To examine the extent to which insurance is associated with access to timely breast cancer diagnosis and breast cancer stage differences among a large, diverse population of US patients with breast cancer.

Design, Setting, and Participants

This retrospective, cross-sectional population-based study used data from the Surveillance, Epidemiology, and End Results Program on 177 075 women aged 40 to 64 years who received a diagnosis of stage I to III breast cancer between January 1, 2010, and December 31, 2016. Statistical analysis was performed from August 1, 2017, to October 1, 2019.

Main Outcomes and Measures

The primary outcome was the risk of having a more advanced stage of breast cancer at diagnosis (ie, stage III vs stages I and II). Mediation analyses were conducted to determine associations of race/ethnicity and proportion of observed differences mediated by health insurance status with earlier stage of diagnosis.

Results

A total of 177 075 women (mean [SD] age, 53.5 [6.8] years; 148 124 insured and 28 951 uninsured or receiving Medicaid) were included in the study. A higher proportion of women either receiving Medicaid or who were uninsured received a diagnosis of locally advanced breast cancer (stage III) compared with women with health insurance (20% vs 11%). In multivariable models, non-Hispanic black (odds ratio [OR], 1.46 [95% CI, 1.40-1.53]), American Indian or Alaskan Native (OR, 1.31 [95% CI, 1.07-1.61]) and Hispanic (OR, 1.35 [95% CI, 1.30-1.42]) women had higher odds of receiving a diagnosis of locally advanced disease (stage III) compared with non-Hispanic white women. When adjusting for health insurance and other socioeconomic factors, associations between race/ethnicity and risk of locally advanced breast cancer were attenuated (non-Hispanic black: OR, 1.29 [95% CI, 1.23-1.35]; American Indian or Alaskan Native: OR, 1.11 [95% CI, 0.91-1.35]; Hispanic: OR, 1.17 [95% CI, 1.12-1.22]). Nearly half (45%-47%) of racial differences in the risk of locally advanced disease were mediated by health insurance.

Conclusions and Relevance

This study's findings suggest that nearly half of the observed racial/ethnic disparities in higher stage at breast cancer diagnosis are mediated by health insurance coverage.

Time to surgery among women treated with neoadjuvant systemic therapy and upfront surgery for breast cancer

PURPOSE

Time to surgery (TTS) is a potentially modifiable factor associated with survival after breast cancer diagnosis and can serve as a proxy for quality of oncologic care coordination. We sought to determine whether factors associated with delays in TTS vary between patients who receive neoadjuvant systemic therapy (NST) vs upfront surgery and whether the impact of these delays on overall survival (OS) varies with treatment sequence.

METHODS

Women ≥ 18 years old with Stage I-III breast cancer were identified in the National Cancer Database (2004-2014). Multivariate linear regression stratified by treatment sequence (upfront surgery vs NST [neoadjuvant chemotherapy {NAC}, neoadjuvant endocrine therapy {NAE}, or both {NACE}]) was used to identify factors associated with TTS. Cox proportional hazards models were used to estimate the effect of TTS on overall survival (OS).

RESULTS

Of 693,469 patients, 14.8% (n = 102,326) received NST (NAC n = 85,143, NAE n = 10,004, NACE n = 7179). Non-White race/ethnicity, no or government-issued insurance, more extensive surgery (i.e., mastectomy and contralateral prophylactic mastectomy vs breast-conserving surgery), and post-mastectomy reconstruction were associated with significantly longer adjusted TTS for NAC and upfront-surgery recipients, but only upfront-surgery patients had progressively worse OS with increasing TTS (> 180 vs ≤ 30 days: HR = 1.31, all p < 0.001).

CONCLUSIONS

Surgery extent, race/ethnicity, and insurance were associated with TTS across treatment groups, but longer TTS was only associated with worse OS in upfront-surgery patients. Our findings can help inform surgeon-patient communication, shared decision making, care coordination, and patients' expectations throughout both NST and in the perioperative period.

Examining breast cancer disparities in African Americans with suggestions for policy

Breast cancer is a commonly diagnosed malignancy and the second leading cause of cancer-related death among American women today. The literature suggests that African American Women (AAW) are more likely to die from the disease each year compared to their White counterparts. A biological basis for this disparity exists-early age of onset, more advanced stage of the disease, more aggressive histological changes, and worse survival. Even though mechanisms underlying these disparities are poorly understood, recent studies suggest that the poorer breast cancer outcome observed in AAW may, in part, result from underlying molecular factors. The present review was undertaken to investigate if AAW do, in fact, develop a more aggressive form of breast cancer compared to other racial groups based on molecular level differences and social determinants. This review also addresses health policy changes that may be implemented to aid in eliminating this disparity.

Executive Summary of the Early-Onset Breast Cancer Evidence Review Conference

The Centers for Disease Control and Prevention launched the Bring Your Brave campaign to increase knowledge about early-onset breast cancer, defined as breast cancer in women aged 18-45 years. The American College of Obstetricians and Gynecologists convened a panel of experts in breast disease from the Society for Academic Specialists in General Obstetrics and Gynecology to review relevant literature, validated tools, best practices, and practice guidelines as a first step toward developing educational materials for women's health care providers about early-onset breast cancer. Panel members conducted structured literature reviews, which were then reviewed by other panel members and discussed at an in-person meeting of stakeholder professional and patient advocacy organizations in April 2019. This article summarizes the relevant literature, existing guidance, and validated tools to guide health care providers in the prevention, early detection, and special considerations of early-onset breast cancer. Substantive knowledge gaps were noted and summarized to provide guidance for future research.

Breast cancer survivorship care beyond local and systemic therapy

Despite persistent inequities in access to care and treatments, advances in combined modality care have led to a steady improvement in outcomes for breast cancer patients across the globe. When estimating the magnitude of clinical benefit of therapies, providers and patients must contend with a multitude of factors that impact treatment decisions and can have long-term effects on quality of life and survival. These include commonly described early toxicities, like aromatase inhibitor-associated musculoskeletal syndrome and neuropathy. But longer-term comorbidities often observed among cancer survivors including weight gain, obesity, infertility, psychological distress, sexual dysfunction, second cancers, bone loss, and body image issues can have lasting effects on quality of life. Equally important, system-level factors such as access to care and resource allocation can have a systemic impact on survival and on the quality of survivorship. Financial toxicity including underemployment can have a lasting impact on patients and caregivers. The resulting disparities in access to treatment can help explain much of the observed variability in outcomes, even within high-income countries like the US. This article revisits some of secondary effects from therapies discussed in a prior 2015 review article, along with other impediments to the optimal delivery of breast cancer care that can affect patients anywhere.

Hinokiflavone induces apoptosis and inhibits migration of breast cancer cells via EMT signalling pathway

Hinokiflavone is a natural product, isolated from Selaginella P. Beauv, Juniperus phoenicea and Rhus succedanea. Even though hinokiflavone was reported to possess cytotoxicity to many cancer cells, and has potential in cancer treatment, the anti‐proliferation and anti‐metastasis efficacy of hinokiflavone on human breast cancer cells has not a further research. In this study, we investigated the anti‐cancer activity of hinokiflavone in human breast cancer cells in vitro and in vivo. Hinokiflavone exhibited a time‐ and dose‐dependent manner apoptosis induction by upregulating expression of Bax and downregulating Bcl‐2 in breast cancer cells. Furthermore, hinokiflavone significantly inhibited the migration and invasion of breast cancer cells by impairing the process of epithelial‐to‐mesenchymal transition. In addition, the tumour growth was distinctly inhibited by treatment of hinokiflavone in a xenograft tumour mouse model of MDA‐MB‐231 cells. Immunohistochemical analysis of tumour sections showed that MMP‐2⁺ cells and Ki‐67⁺ cells were remarkably decreased in tumour tissues of mice after treatment of hinokiflavone, indicating that hinokiflavone inhibits not only proliferation but also metastasis of breast cancer cells. Our study suggested that hinokiflavone can be a potential drug to breast cancer.

Significance of the study

Hinokiflavone significantly inhibited proliferation and induced apoptosis in breast cancer cells. In addition, hinokiflavone remarkably inhibited migration and invasion of breast cancer cells via EMT signalling pathway. It is worth noting that hinokiflavone possesses anti‐tumour effect in tumour mouse xenograft model of breast cancer. Overall, our results indicated that hinokiflavone may be a potential anticancer drug for breast cancer treatment.

Premenopausal gynecologic surgery and survival among black and white women with breast cancer

PURPOSE

In the United States, hysterectomies and oophorectomies are frequently performed before menopause for benign conditions. The procedures are associated with reduced breast cancer-specific mortality among White women. The relationship between premenopausal gynecologic surgery and mortality in Black women with breast cancer is unknown.

METHODS

This investigation used incident invasive cases of breast cancer from Phases 1 and 2 of the Carolina Breast Cancer Study a population-based study that recruited Black and White women in North Carolina between 1993 and 2001. Premenopausal gynecologic surgery was operationalized in three categories: no surgery; hysterectomy with bilateral oophorectomy; hysterectomy with conservation of ≥ 1 ovary. Mortality was ascertained using the National Death Index, last updated in 2016. Multivariable-adjusted Cox Proportional Hazard Models were used to estimate the effect of premenopausal surgery on breast cancer-specific and all-cause mortality RESULTS: Hysterectomy with bilateral oophorectomy was associated with reduced breast cancer-specific mortality (HR 0.68; 95% CI 0.49, 0.96). White and Black women had a similar reduction in breast cancer-specific mortality. (HR among white: 0.66; 95% CI 0.43, 1.02), (HR among Black: 0.67; 95% CI 0.37, 1.21).

CONCLUSIONS

There was a similar reduction in breast cancer-specific mortality following premenopausal, pre-diagnosis hysterectomy with bilateral oophorectomy across both Black and White women.

Breast Cancer in San Francisco: Disentangling Disparities at the Neighborhood Level

BACKGROUND

This study uses a novel geographic approach to summarize the distribution of breast cancer in San Francisco and aims to identify the neighborhoods and racial/ethnic groups that are disproportionately affected by this disease.

METHODS

Nine geographic groupings were newly defined on the basis of racial/ethnic composition and neighborhood socioeconomic status. Distribution of breast cancer cases from the Greater Bay Area Cancer Registry in these zones were examined. Multivariable logistic regression models were used to determine neighborhood associations with stage IIB⁺ breast cancer at diagnosis. Cox proportional hazards regression was used to estimate the hazard ratios for all-cause and breast cancer-specific mortality.

RESULTS

A total of 5,595 invasive primary breast cancers were diagnosed between January 1, 2006 and December 31, 2015. We found neighborhood and racial/ethnic differences in stage of diagnosis, molecular subtype, survival, and mortality. Patients in the Southeast (Bayview/Hunter's Point) and Northeast (Downtown, Civic Center, Chinatown, Nob Hill, Western Addition) areas were more likely to have stage IIB⁺ breast cancer at diagnosis, and those in the East (North Beach, Financial District, South of Market, Mission Bay, Potrero Hill) and Southeast were more likely to be diagnosed with triple-negative breast cancers (TNBC). Compared with other racial/ethnic groups, Blacks/African Americans (B/AA) experienced the greatest disparities in breast cancer-related outcomes across geographic areas.

CONCLUSIONS

San Francisco neighborhoods with lower socioeconomic status and larger minority populations experience worse breast cancer outcomes.

IMPACT

Our findings, which reveal breast cancer disparities at sub-county geographic levels, have implications for population-level health interventions.

The Difference of Expression of 18 Genes in Axillary Invasion and Vascular Invasion Compared to Control Samples in Breast Cancer

Background & Objective:

Recent studies from gene profiling have revealed some genes that are overexpressed in the epithelial-mesenchymal transition (EMT) process and are responsible for its initiation and activation resulting in tumor progression and metastasis. The present study aimed to assess the role of genes involved in the EMT process and the association of these genes with axillary lymph node and vascular invasion in breast cancer (BC) patients.

Methods:

In this case-control study, the tumor samples were initially extracted from 33 BC patients. The samples of 15 BC tissues without vascular and axillary invasion were also prepared from the biobank as a control group. RNAs from both tumor and control samples were extracted and stabilized. For assessing overexpression in tumor tissues of selected 18 genes, the real time technique was employed.

Results:

There was a significant increase in MMP-2 gene fold expression in tumor cells with vascular invasion regardless of axillary involvement compared to the control group (P=0.0008) and also in the comparison of the control group with those with vascular invasion and not axillary lymph node involvement (P=0.003). In addition, gene fold expression of tissue inhibitors of metalloproteinase-1(TIMP-1) was decreased in axillary involving tumor cells compared to control group (P=0.045), and also in comparison with all samples that did not present any axillary lymph node involvements including the control group and the group with isolated vascular invasion (P=0.012).

Conclusion:

Overexpression of MMP-2 and under-expression of TIMP-1 were associated with more invasive behavior in breast tumor cells.

Lobaplatin-based regimens outperform cisplatin for metastatic breast cancer after anthracyclines and taxanes treatment

The goal of this study was to assess the antitumor efficacy and safety of lobaplatin-based regimens as the second line of treatment in patients with metastatic breast cancer (MBC) resistant to anthracyclines and taxanes, compared with that of cisplatin-based regimens. During August 2012 to April 2015, 87 patients who received lobaplatin-based regimens or cisplatin-based regimens were included. Medical records of the patients noted that lobaplatin (30 mg/m2) or cisplatin (25 mg/m2), combined with another chemotherapeutic agent such as Gemcitabine (1000 mg/m2) or Vinorelbine (25 mg/m2), was intravenously given to the patients on a basis of twenty-one days as one treatment cycle. All the patients were followed until August 2017. The endpoint of this study was progression-free survival (PFS), overall survival (OS), and estimated objective response rate (RR). Safety and drug tolerability data were also obtained. Lobaplatin-based regimens prolonged PFS compared to cisplatin-based regimens (median 13.2 vs 4.7 months, hazard ratio = 0.37, 95% confidence intervals: 0.21-0.67, P = .0007), while OS was not significantly different between the two groups (hazard ratio = 0.72, 95% confidence intervals: 0.40-1.30, P = .2767), as was objective RR (37.8% vs 33.4%, x 2 = 0.19, P = .6653). Nausea/vomiting and renal injury were more frequent with cisplatin-based regimens. Our results show that lobaplatin-based regimens are superior to cisplatin in terms of efficacy and are better tolerated.

Emerging Data and Current Challenges for Young, Old, Obese, or Male Patients with Breast Cancer

There are distinct subgroups of patients who have historically been underrepresented in most prospective clinical trials in breast cancer, including the youngest and oldest patients, male patients, and those struggling with obesity. Herein, we review current and future directions in research for each of these special populations with breast cancer, highlighting significant knowledge gaps and priorities in tumor biology and heterogeneity, therapeutic decision making promotion of adherence, supportive care, and psychosocial and functional well-being. In younger women, future study should focus on the biological underpinnings of aggressive disease and optimizing adherence and treatment decision making while addressing their unique survivorship needs. The latter includes generating a scientific basis for interruption of therapy for pregnancy. Among older patients, interventions should focus on increasing clinical trial accrual, predicting and mitigating toxicity so that functional status can be optimized, tailoring needs for dose modification, and anticipating life expectancy in the context of competing causes of death. For men with breast cancer, we need worldwide collaboration to answer even basic questions on optimal treatment, supportive care, and survivorship strategies. Finally, for those struggling with obesity, we need to better understand the biological associations with cancer incidence, prognosis and outcome, and how we can best intervene to assure weight loss at the "right time." It is only through highly collaborative, far-reaching, prospective, multidisciplinary, patient-centered, and patient-engaged efforts that we can optimize the physical and psychologic outcomes for all patients with breast cancer. Clin Cancer Res; 23(11); 2647-54. ©2017 AACRSee all articles in this CCR Focus section, "Breast Cancer Research: From Base Pairs to Populations."

Unmet Needs in Clinical Research in Breast Cancer: Where Do We Need to Go?

This CCR Focus highlights areas in breast cancer research with the greatest potential for clinical and therapeutic application. The articles in this CCR Focus address the state of the science in a broad range of areas with a focus on "hot" although sometimes controversial topics, unanswered questions, and unmet need. From mutational signatures, the cancer genomic revolution, and new inroads in immunotherapy for breast cancer to unique concerns of vulnerable populations as well as national and global health disparities, these works represent much of the promise of breast cancer research as well as the challenges in the coming years. Each review focuses not only on recent discoveries but also on putting the topic in context, including limitations to overcome. This overview is designed to further contextualize the highlighted issues within the broader research landscape. We also present new information from a poll of ALLIANCE for Clinical Trials in Oncology Breast Committee members regarding the most needed and viable potential future National Cancer Institute (NCI)-supported clinical trials in breast cancer. The great challenge is to translate the potential benefits of greater scientific knowledge reflected in this CCR Focus section into improvements in outcomes for individuals and populations with breast cancer. A unifying theme across the six articles contained in this CCR Focus is the increasingly recognized value and necessity of collaboration across disciplines from bench to bedside to populations. Only continued and iteratively amplified scientific, clinical, and governmental commitment to creating, testing, and implementing new knowledge will reduce the global morbidity and mortality of breast cancer. Clin Cancer Res; 23(11); 2611-6. ©2017 AACRSee all articles in this CCR Focus section, "Breast Cancer Research: From Base Pairs to Populations."

Immunotherapy for Breast Cancer: What Are We Missing?

The recent demonstration of modest single-agent activity of programmed death-ligand 1 (PD-L1) and programmed death receptor-1 (PD-1) antibodies in patients with breast cancer has generated hope that breast cancer can be made amenable to immunotherapy. Depending on the subtype of breast cancer, it is now clear in both primary and metastatic disease that the extent of tumor-infiltrating T cells is not only prognostic for survival but predictive of response to nonimmune, standard therapies. Despite these findings, immune cytolytic activity in spontaneous breast tumors, the burden of nonsynonymous tumor mutations, and the predicted load of neoepitopes-factors linked to response to checkpoint blockade in other malignancies-are all relatively modest in breast cancer compared with melanoma or lung cancer. Thus, in breast cancer, combinations of immune agents with nonredundant mechanisms of action are high-priority strategies. For most breast cancers that exhibit relatively modest T-cell infiltration, major challenges include immune suppression in the tumor microenvironment as well as failed or suboptimal T-cell priming. Agents that trigger de novo T-cell responses may be critical for the successful development of cancer immunotherapy and immune prevention in breast cancer. Success may also require reaching beyond nonsynonymous mutations as the T-cell epitopes to target, especially as numerous unmutated proteins were validated as breast cancer-associated antigens in the pre-checkpoint era. A deeper understanding of the immunobiology of breast cancer will be critical for immunotherapy to become broadly relevant in this disease. Clin Cancer Res; 23(11); 2640-6. ©2017 AACRSee all articles in this CCR Focus section, "Breast Cancer Research: From Base Pairs to Populations."

Mutational Signatures in Breast Cancer: The Problem at the DNA Level

A breast cancer genome is a record of the historic mutagenic activity that has occurred throughout the development of the tumor. Indeed, every mutation may be informative. Although driver mutations were the main focus of cancer research for a long time, passenger mutational signatures, the imprints of DNA damage and DNA repair processes that have been operative during tumorigenesis, are also biologically illuminating. This review is a chronicle of how the concept of mutational signatures arose and brings the reader up-to-date on this field, particularly in breast cancer. Mutational signatures have now been advanced to include mutational processes that involve rearrangements, and novel cancer biological insights have been gained through studying these in great detail. Furthermore, there are efforts to take this field into the clinical sphere. If validated, mutational signatures could thus form an additional weapon in the arsenal of cancer precision diagnostics and therapeutic stratification in the modern war against cancer. Clin Cancer Res; 23(11); 2617-29. ©2017 AACRSee all articles in this CCR Focus section, "Breast Cancer Research: From Base Pairs to Populations."