Disease characteristics and mortality among Asian women with breast cancer

Genomic Landscape of Breast Cancer: Study Across Diverse Ethnic Groups

Background: Breast cancer (BC) is the most common cancer among women worldwide, with incidence and mortality rates varying across ethnic groups due to sociodemographic, clinicopathological, and genomic differences. This study aimed to characterize the genomic landscape of BC in diverse ethnic groups using computational tools to explore these variations. Methodology: cBioPortal was used to analyze genomic, clinicopathological, and sociodemographic data from 1084 BC samples. Mutated genes were classified based on GeneCards platform data. Enrichment analysis was performed with CancerHallmarks, and genes not found were compared with MSigDB's Hallmark Gene Sets. Genes absent from both were further analyzed using NDEx through Cytoscape.org to explore their role in cancer. Results: Significant differences (p < 0.05) were observed in sex, tumor subtypes, genetic ancestry, median of the fraction of the altered genome, mutation count, and mutation frequencies of genes across ethnic groups. We identified the most frequently mutated genes. Some of these genes were found to be associated with classic cancer hallmarks, such as replicative immortality, sustained proliferative signaling, and the evasion of growth suppressors. However, the exact role of some of these genes in cancer remains unclear, highlighting the need for further research to better understand their involvement in tumor biology. Conclusions: This study identified significant clinicopathological and genomic variations in BC across ethnic groups. While key genes associated with cancer hallmarks were found, the incomplete characterization of some highlights the need for further research, especially focusing on ethnic groups, to understand their role in tumor biology and improve personalized treatments.

Breast cancer beliefs and screening behaviors among South Asian immigrant women living in the United States

BACKGROUND

Breast cancer incidence is increasing among South Asian women in the United States (US). This qualitative study explored breast cancer beliefs, behaviors, and experiences among South Asian immigrant women in New Jersey (NJ).

METHODS

We conducted four online focus groups with South Asian women from NJ, aged ≥ 25 years with no prior history of cancer, in English, between June 2021 and July 2022. Thematic content analysis was guided by the Social Contextual Framework.

RESULTS

We recruited 22 participants, average age 52 (standard deviation (SD) = 8.4) years, all born in South Asia, and living in the US for an average of 26 (SD = 11.7) years. Low perceived individual risk of breast cancer was influenced by no family history and healthy lifestyles. Despite diet changes since immigrating and misconceptions held by some, women understood the benefits of mammography. Interpersonal and cultural barriers included family responsibilities and norms deprioritizing women's health and health-seeking behaviors. Access to care may be limited by structural factors including immigration status, insurance, and language barriers. Social norms regarding stigma, modesty, and self-disclosure may vary by generation and context.

CONCLUSIONS

Despite low perceived breast cancer risk and some cultural and structural barriers to screening, South Asian immigrant women generally understood mammography's early detection benefits. Culturally appropriate interventions leveraging family ties and social networks are needed to dispel misconceptions, promote health-seeking behaviors, and address structural barriers.

Breast Cancer Risk and Management in the Endocrine Clinic: A Comprehensive Review

OBJECTIVE

This review seeks to provide endocrine clinicians with a comprehensive analysis of breast cancer risk, diagnostic modalities and management strategies in women with endocrine disorders, with particular emphasis on the influence of metabolic factors such as diabetes and obesity, and the role of Menopausal Hormone Therapy (MHT).

DESIGN

The review examines a spectrum of endocrine disorders commonly encountered in clinical practice, including Multiple Endocrine Neoplasia Types 1 (MEN1), 2 (MEN2) and 4 (MEN4), Von Hippel-Lindau syndrome (VHL), Pheochromocytoma and Paraganglioma (PPGL), Acromegaly, Hyperprolactinaemia, Polycystic Ovary Syndrome (PCOS), Congenital Adrenal Hyperplasia (CAH), Turner Syndrome, alongside metabolic conditions such as diabetes and obesity and the effects of MHT. The review critically appraises each disorder's association with breast cancer risk, screening implications and therapeutic management.

PATIENTS

This analysis focuses on women with the aforementioned endocrine and metabolic disorders, assessing their specific breast cancer risk profiles, informed by the latest clinical evidence and molecular insights.

MEASUREMENTS

The review comprehensively evaluates current evidence-based approaches to screening, diagnostic accuracy and treatment in this patient cohort. Emphasis is placed on the metabolic derangements, hormonal influences and genetic predispositions that modulate breast cancer risk, providing disorder-specific recommendations for individualised care.

RESULTS

The findings indicate a significantly elevated breast cancer risk in patients with MEN1, necessitating early initiation of MRI screening by age 40. In MEN2, emerging evidence suggests that combining RET inhibitors with endocrine therapy may yield clinical benefits, although further research is needed to validate this approach. The breast cancer risk associated with MEN4 and VHL syndromes, while documented, remains less well-characterised, requiring further investigation. Diabetes and obesity are confirmed as major modifiable risk factors, particularly in postmenopausal women, where hyperinsulinemia and metabolic dysfunction contribute to increased incidence and poorer outcomes, notably in triple-negative breast cancer (TNBC). The role of MHT, particularly combined oestrogen-progestogen therapy, is strongly associated with increased breast cancer risk, particularly for hormone receptor-positive malignancies, necessitating cautious use and personalised treatment planning. In contrast, oestrogen-only MHT appears to confer a reduced risk in women post-hysterectomy. For patients with PCOS, CAH and Turner Syndrome, while definitive evidence of elevated breast cancer risk is lacking, individualised screening strategies and careful hormone therapy management remain essential due to the complex interplay of hormonal and metabolic factors.

CONCLUSIONS

The review highlights the need for personalised breast cancer screening and management protocols in women with endocrine and metabolic disorders. For high-risk groups such as MEN1 patients, early initiation of MRI screening is warranted. In women with diabetes and obesity, targeted interventions addressing hyperinsulinemia and metabolic dysfunction are critical to mitigating their increased cancer risk. The association between MHT and breast cancer underscores the importance of individualised risk stratification in hormone therapy administration, particularly in women with predisposing genetic or endocrine conditions. Enhanced surveillance tailored to the unique risk profiles of endocrine disorder patients will facilitate early detection and improve clinical outcomes. However, further large-scale studies are necessary to refine these associations and develop robust, evidence-based guidelines.

Comparison of incident breast cancer cases in the largest national US tumor registries

BACKGROUND

This study compared incident breast cancer cases in the National Cancer Database (NCDB) and Surveillance, Epidemiology, End Results Program (SEER) to a national population cancer registry.

METHODS

Patients with malignant or in situ breast cancer (BC) 2010-2019 in the NCDB and SEER were compared to the US Cancer Statistics (USCS). Case coverage was estimated as the number of patients in the NCDB/SEER as a proportion of USCS cases.

RESULTS

The USCS reported 3,047,509 patients; 77.5% patients were included in the NCDB and 46.0% in SEER. Case ascertainment varied significantly by patient sex (both registries, p < .001). For males, 84.1% were captured in the NCDB, whereas only 77.5% of females were included. Case coverage in SEER was better for females than males (46.1% vs. 43.5%). Registries varied significantly by race/ethnicity (both p < .001). Case coverage in the NCDB was highest for non-Hispanic White (78.2%), non-Hispanic Black (77.7%), and non-Hispanic Asian or Pacific Islander (72.5%) BC patients, and lowest for Hispanic (56.4%) and non-Hispanic American Indian/Alaska Native (41.1%) patients. In SEER, case coverage was highest for non-Hispanic Asian or Pacific Islander (78.1%) and Hispanic (69.6%) patients and it was significantly lower for all other subgroups (non-Hispanic Black, 44.8%; non-Hispanic White, 42.4%; and non-Hispanic American Indian/Alaska Native, 36.6%).

CONCLUSIONS

National US tumor registries provide data for a large sampling of breast cancer patients, yet significant differences in case coverage were observed based on age, sex, and race/ethnicity. These findings suggest that analyses using these data sets and interpretation of findings should account for these meaningful variances.

Cultural and Linguistic Adaptation of an Evidence-Based Tailored Navigation Intervention to Increase Cancer Screening Uptake Among Southeast Asian Women

BackgroundSoutheast Asian immigrant women in the U.S. have high rates of breast and cervical cancer, yet they are the least likely of all racial/ethnic groups to get screened. To address this disparity, we adapted the evidence-based Tailored Intervention Messaging System© (TIMS©), which uses tailored messages and navigation by culturally and linguistically matched community health advisors to overcome barriers to cancer screening.ObjectivesThis study describes the cultural and linguistic adaptation of TIMS© to improve breast and cervical cancer screening among Southeast Asian immigrant women in the U.S.MethodsGuided by Stirman et al.'s adaptation framework, we conducted focus groups and in-depth interviews to identify key constructs related to cancer screening (knowledge, perceived barriers, perceived risk, benefits, self-efficacy). Using the TIMS© and the thematic content from qualitative data, we modified messages for content and context. Messages were divided into three categories: 1) existing messages identified in thematic analyses, 2) existing messages not identified in thematic analyses, and 3) new messages that emerged from thematic analyses.ResultsContextual and content modifications were made to the TIMS© message library. Messages were translated into Lao, Khmer, and Vietnamese. Through an iterative process, the investigator, community health advisors, and cultural community advisory board members reviewed and revised the messages for translation accuracy, relevance, and clarity.ConclusionUsing relatable language and context is critical to engaging women from Southeast Asian communities in improving breast and cervical cancer screening uptake. This adaptation approach can be applied to tailor interventions for other languages, cultures, and underrepresented groups.

Breast cancer statistics 2024

This is the American Cancer Society's biennial update of statistics on breast cancer among women based on high-quality incidence and mortality data from the National Cancer Institute and the Centers for Disease Control and Prevention. Breast cancer incidence continued an upward trend, rising by 1% annually during 2012-2021, largely confined to localized-stage and hormone receptor-positive disease. A steeper increase in women younger than 50 years (1.4% annually) versus 50 years and older (0.7%) overall was only significant among White women. Asian American/Pacific Islander women had the fastest increase in both age groups (2.7% and 2.5% per year, respectively); consequently, young Asian American/Pacific Islander women had the second lowest rate in 2000 (57.4 per 100,000) but the highest rate in 2021 (86.3 per 100,000) alongside White women (86.4 per 100,000), surpassing Black women (81.5 per 100,000). In contrast, the overall breast cancer death rate continuously declined during 1989-2022 by 44% overall, translating to 517,900 fewer breast cancer deaths during this time. However, not all women have experienced this progress; mortality remained unchanged since 1990 in American Indian/Alaska Native women, and Black women have 38% higher mortality than White women despite 5% lower incidence. Although the Black-White disparity partly reflects more triple-negative cancers, Black women have the lowest survival for every breast cancer subtype and stage except localized disease, with which they are 10% less likely to be diagnosed than White women (58% vs. 68%), highlighting disadvantages in social determinants of health. Progress against breast cancer could be accelerated by mitigating racial, ethnic, and social disparities through improved clinical trial representation and access to high-quality screening and treatment.

Differences in Breast Cancer Subtypes among Racial/Ethnic Groups

BACKGROUND

Differences in the incidence of breast cancer subtypes among racial/ethnic groups have been evaluated as a contributing factor in disparities seen in breast cancer prognosis. We evaluated new breast cancer cases in Hawai'i to determine if there were subtype differences according to race/ethnicity that may contribute to known disparities.

METHODS

We reviewed 4591 cases of women diagnosed with breast cancer from two large tumor registries between 2015 and 2022. We evaluated breast cancer cases according to age at diagnosis, self-reported race, breast cancer subtype (ER, PR, and HER2 receptor status), histology, county, and year.

RESULTS

We found both premenopausal and postmenopausal Native Hawaiian women were less likely to be diagnosed with triple-negative breast cancer (OR = 0.26, 95% CI 0.12-0.58 p = 0.001; OR = 0.54, 95% CI 0.36, 0.80 p = 0.002, respectively).

CONCLUSIONS

The results of our study support that there are racial/ethnic differences in breast cancer subtypes among our population, which may contribute to differences in outcomes. Further evaluation of clinical and pathological features in each breast cancer subtype may help improve the understanding of outcome disparities seen among different racial/ethnic groups.

Epidemiology of early vs late recurrence among women with early stage estrogen receptor-positive breast cancer in the Pathways Study

BACKGROUND

Relatively little is known about the differences in prognostic factors for early vs late recurrence among women with early stage estrogen receptor-positive breast cancer.

METHODS

We analyzed factors related to early (<5 years) vs late (≥5 years) recurrence in 2992 women with stage I-IIB estrogen receptor-positive breast cancer in the Pathways Study, a prospective cohort of women with breast cancer enrolled between 2006 and 2013, with ascertainment of recurrence and death through December 2021.

RESULTS

After a median follow-up of 13.3 years, 341 (13.8%) women had recurrences, including 181 (53.7%) with late recurrence. Higher stage and grade were associated with recurrence regardless of timing, whereas progesterone receptor negativity was associated with early but not late recurrence. Receipt of endocrine therapy was associated with reduced risk of overall recurrence, but the length of endocrine therapy was not statistically significant in multivariable models. Minoritized racial and ethnic groups, including Asian, Black, and Hispanic women, had higher risk of early but not late recurrence compared to non-Hispanic White women. The trend of higher risk of early recurrence among these groups remained after adjustment for clinical, demographic, and socioeconomic factors but was statistically significant only in Asian women.

CONCLUSIONS

Our study revealed potentially important distinctions for early vs late recurrence, including the associations with progesterone receptor negativity and self-identified race and ethnicity. Possible higher risk of early recurrence among Asian, Black, and Hispanic women provides novel evidence for the existence of disparities in cancer outcomes, even within the breast cancer subtype indicative of generally good prognosis.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with early breast cancer

The European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with early breast cancer were updated and published online in 2023, and adapted, according to previously established standard methodology, to produce the Pan-Asian adapted (PAGA) ESMO consensus guidelines for the management of Asian patients with early breast cancer. The adapted guidelines presented in this manuscript represent the consensus opinions reached by a panel of Asian experts in the treatment of patients with breast cancer representing the oncological societies of China (CSCO), Indonesia (ISHMO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), the Philippines (PSMO), Singapore (SSO), Taiwan (TOS) and Thailand (TSCO), co-ordinated by ESMO and KSMO. The voting was based on scientific evidence and was independent of the current treatment practices, drug access restrictions and reimbursement decisions in the different Asian regions represented by the 10 oncological societies. The latter are discussed separately in the manuscript. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with early breast cancer across the different regions of Asia, drawing on the evidence provided by both Western and Asian trials, whilst respecting the differences in screening practices, molecular profiling, as well as the age and stage at presentation. Attention is drawn to the disparity in the drug approvals and reimbursement strategies, between the different regions of Asia.

Radiation Therapy Practice Patterns for Treatment of Curative Breast Cancer in a Large Tertiary Health Care System

Purpose

Disparities have been reported in women treated for breast cancer (BrCa). This study examines potential disparities in BrCa treatment offered based on race and age from a multicenter radiation department.

Methods and Materials

We identified 901 patients with early stage BrCa who received curative intent radiation therapy (RT) between 2004 and 2018. Data extracted included age, race, disease stage, treatment technique, treatment dates, and fractionation. Patient race was recorded as Asian, Black, Hispanic, and White. RT technique delivered was classified as a type of external beam radiation therapy or brachytherapy/intraoperative radiation therapy. Fractionation schema were defined as 1) standard fractionation, 1.8-2 Gy; 2) hypofractionation, 2.5-2.67 Gy; 3) accelerated partial breast irradiation (APBI), 3.4 Gy - 4.25 Gy, and 4) intraoperative radiation therapy, single dose of 20 Gy. Stage was recorded using TNM staging. The χ2 test and a multivariable multinomial logistic regression model were used to assess whether patient characteristics, such as age, race, or stage influenced fractionation schemes. Results with 2-sided P values < .05 were considered statistically significant.

Results

Racial composition of the study was 13.8% Asian, 22% Black, 29%, White, and 35.1% Hispanic. Mean age was 61 and was divided into 4 age range groups: 30 to 49 (n = 160), 50 to 59 (n = 231), 60 to 69 (n = 294), and ≥70 years (n = 216). In addition, 501 patients (56%) received hypofractionation, 342 (38.8%) received standard fractionation, and 58 (7.1%) received APBI, respectively. For all groups, hypofractionation became more common over time. Age ≥70 years was associated with 9 times higher odds of APBI and 14 times higher odds of hypofractionation, compared with age 30 to 49 years. After adjusting for the other predictors in a multivariable multinomial logistic regression model, the race distribution differed among the 3 groups (P = .03), with a smaller percentage of Hispanics and higher percentage of blacks in the standard group.

Conclusions

This study of a diverse cohort of patients with breast cancer failed to identify treatment differences associated by race. The study found an association between age and hypofractionation.

Risk of contralateral breast cancer among Asian/Pacific Islander women in the United States

PURPOSE

While breast cancer studies often aggregate Asian/Pacific Islander (API) women, as a single group or exclude them, this population is heterogeneous in terms of genetic background, environmental exposures, and health-related behaviors, potentially resulting in different cancer outcomes. Our purpose was to evaluate risks of contralateral breast cancer (CBC) among subgroups of API women with breast cancer.

METHODS

We conducted a retrospective cohort study of women ages 18 + years diagnosed with stage I-III breast cancer between 2000 and 2016 in the Surveillance, Epidemiology and End Results registries. API subgroups included Chinese, Japanese, Filipina, Native Hawaiian, Korean, Vietnamese, Indian/Pakistani, and other API women. Asynchronous CBC was defined as breast cancer diagnosed in the opposite breast 12 + months after first primary unilateral breast cancer. Multivariable-adjusted subdistribution hazard ratios (SHR) and 95% confidence intervals (CI) were estimated and stratified by API subgroups.

RESULTS

From a cohort of 44,362 API women with breast cancer, 25% were Filipina, 18% were Chinese, 14% were Japanese, and 8% were Indian/Pakistani. API women as an aggregate group had increased risk of CBC (SHR 1.15, 95% CI 1.08-1.22) compared to NHW women, among whom Chinese (SHR 1.23, 95% CI 1.08-1.40), Filipina (SHR 1.37, 95% CI 1.23-1.52), and Native Hawaiian (SHR 1.69, 95% CI 1.37-2.08) women had greater risks.

CONCLUSION

Aggregating or excluding API patients from breast cancer studies ignores their heterogeneous health outcomes. To advance cancer health equity among API women, future research should examine inequities within the API population to design interventions that can adequately address their unique differences.

Racial disparities in surgical outcomes after mastectomy in 223 000 female breast cancer patients: a retrospective cohort study

BACKGROUND

Breast cancer mortality and treatment differ across racial groups. It remains unclear whether such disparities are also reflected in perioperative outcomes of breast cancer patients undergoing mastectomy.

STUDY DESIGN

The authors reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database (2008-2021) to identify female patients who underwent mastectomy for oncological purposes. The outcomes were stratified by five racial groups (white, Black/African American, Asian, American Indian/Alaska Native, and Native Hawaiian/Pacific Islander) and included 30-day mortality, reoperation, readmission, surgical and medical complications, and non-home discharge.

RESULTS

The study population included 222 947 patients, 68% ( n =151 522) of whom were white, 11% ( n =23 987) Black/African American, 5% ( n =11 217) Asian, 0.5% ( n =1198) American Indian/Alaska Native, and 0.5% ( n =1018) Native Hawaiian/Pacific Islander. While 136 690 (61%) patients underwent partial mastectomy, 54 490 (24%) and 31 767 (14%) women received simple and radical mastectomy, respectively. Overall, adverse events occurred in 17 222 (7.7%) patients, the largest portion of which were surgical complications ( n =7246; 3.3%). Multivariable analysis revealed that being of Asian race was protective against perioperative complications [odds ratio (OR)=0.71; P <0.001], whereas American Indian/Alaska Native women were most vulnerable to the complication occurrence (OR=1.41; P <0.001). Black/African American patients had a significantly lower risk of medical (OR=0.59; P <0.001) and surgical complications (OR=0.60; P <0.001) after partial and radical mastectomy, respectively, their likelihood of readmission (OR=1.14; P =0.045) following partial mastectomy was significantly increased.

CONCLUSION

The authors identified American Indian/Alaska Native women as particularly vulnerable to complications following mastectomy. Asian patients experienced the lowest rate of complications in the perioperative period. The authors' analyses revealed comparable confounder-adjusted outcomes following partial and complete mastectomy between Black and white races. Their findings call for care equalization in the field of breast cancer surgery.

Racial Disparities in Breast Cancer: from Detection to Treatment

PURPOSE OF REVIEW

Update on current racial disparities in the detection and treatment of breast cancer.

RECENT FINDINGS

Breast cancer remains the leading cause of cancer death among Black and Hispanic women. Mammography rates among Black and Hispanic women have surpassed those among White women, with studies now advocating for earlier initiation of breast cancer screening in Black women. Black, Hispanic, Asian, and American Indian and Alaskan Native women continue to experience delays in diagnosis and time to treatment. Further, racial discrepancies in receipt of guideline-concordant care, access to genetic testing and surgical reconstruction persist. Disparities in the initiation, completion, toxicity, and efficacy of chemotherapy, endocrine therapy, and targeted drug therapy remain for racially marginalized women. Efforts to evaluate the impact of race and ethnicity across the breast cancer spectrum are increasing, but knowledge gaps remain and further research is necessary to reduce the disparity gap.

A randomized controlled trial testing a virtual program for Asian American women breast cancer survivors

A culturally tailored virtual program could meet the survivorship needs of Asian American women breast cancer survivors (AABC). This study aims to determine the efficacy of a culturally tailored virtual information and coaching/support program (TICAA) in improving AABC's survivorship experience. A randomized clinical trial (NCT02803593) was conducted from January 2017 to June 2020 among 199 AABC. The intervention group utilized TICAA and the American Cancer Society [ACS] website while the control group used only ACS website for 12 weeks. The outcomes were measured using the SCNS-34SF (needs; primary), the MSAS-SF (symptoms; secondary), and the FACT-B (quality of life; secondary). The data were analyzed using an intent-to-treat approach. The intervention group showed significant reductions in their needs from the baseline (T0) to post 4 weeks (T1) and to post 12 weeks (T2). Although the changes were not statistically significant, the intervention group had decreased symptoms from T0 to T2 while the control group had an increase in their symptoms. The intervention group had a significant increase in their quality of life from T0 to T2. A culturally tailored virtual program could therefore improve quality of life in AABC patients. Trial Registration: To Enhance Breast Cancer Survivorship of Asian Americans (TICAA), NCT02803593, https://clinicaltrials.gov/ct2/show/NCT02803593?titles=TICAA&draw=2&rank=1.

Survival of Filipino women with breast cancer in the United States

BACKGROUND

The survival of women with early-stage breast cancer varies by racial group. Filipino women with breast cancer are an understudied group and are often combined with other Asian groups. We compared clinical presentations and survival rates for Filipino and White women with breast cancer diagnosed in the United States.

METHODS

We conducted a retrospective cohort study of women with breast cancer diagnosed between 2004 and 2015 in the SEER18 registries database. We compared crude survival between Filipino and White women. We then calculated adjusted hazard ratios (HR) in a propensity-matched design using the Cox proportional hazards model.

RESULTS

There were 10,834 Filipino (2.5%) and 414,618 White women (97.5%) with Stage I-IV breast cancer in the SEER database. The mean age at diagnosis was 57.5 years for Filipino women and 60.8 years for White women (p < 0.0001). Filipino women had more high-grade and larger tumors than White women and were more likely to have node-positive disease. Among women with Stage I-IIIC breast cancer, the crude 10-year breast cancer-specific survival rate was 91.0% for Filipino and 88.9% for White women (HR 0.81, 95% CI 0.74-0.88, p < 0.01). In a propensity-matched analysis, the HR was 0.73 (95% CI 0.66-0.81). The survival advantage for Filipino women was present in subgroups defined by age of diagnosis, nodal status, estrogen receptor status, and HER2 receptor status.

CONCLUSION

In the United States, Filipino women often present with more advanced breast cancers than White women, but experience better breast cancer-specific survival.

Addressing Inequalities in Breast Cancer Care Delivery

Breast cancer treatment, timeliness of care, and clinical outcomes are inferior for patients of Black race and Hispanic ethnicity, and the origin of these inequities is multifactorial. Owing to aggregate reporting of data in the United States for patients of Asian, Native Hawaiian, and Pacific Islander ancestry, disparities within and across these groups are difficult to appreciate. In large part due to low prevalence, male breast cancer remains understudied, and treatment algorithms are primarily extrapolated from research conducted in female patients.

Outcomes in breast cancer-does ethnicity matter?

Ethnic or racial differences in breast cancer (BC) survival outcomes have been reported, but current data are largely restricted to comparisons between African Americans and non-Hispanic whites. Most analyses have traditionally been based on self-reported race which may not always be accurate, or are oversimplified in their classification. With increasing globalization, quantification of the genetic ancestry from genomic data may offer a solution to infer the complex makeup from admixture of races. Focusing on the larger and the latest studies, we will discuss recent findings on the differing host and tumor biology that may be driving these disparities, in addition to the extrinsic environmental or lifestyle factors. Socioeconomic disparities with lower cancer literacy may lead to late presentation, poorer adherence to treatment, and other lifestyle factors such as unhealthy diet, obesity, and inadequate physical activity. These hardships may also result in greater allostatic load, which is in turn associated with aggressive BC features in disadvantaged populations. Epigenetic reprogramming may mediate the effects of the environment or lifestyle factors on gene expression, with ensuing differences in BC characteristics and outcome. There is increasing evidence that germline genetics can influence somatic gene alterations or expression, as well as modulate the tumor or immune microenvironment. Although the precise mechanisms remain elusive, this may account for the varying distribution of different BC subtypes across ethnicities. These gaps in our knowledge highlight the need to interrogate the multiomics landscape of BC in diverse populations, ideally in large-scale collaborative settings with standardized methodology for the comparisons to be statistically robust. Together with improving BC awareness and access to good quality health care, a holistic approach with insights of the biological underpinnings is much needed to eradicate ethnic disparities in BC outcomes.

Disparities in stage at diagnosis among breast cancer molecular subtypes in China

BACKGROUND

Disease stage at diagnosis and molecular subtypes are the main determinants of breast cancer treatment strategies and prognosis. We aimed at examining the disparities and factors associated with the stage at diagnosis among the molecular subtypes in breast cancer patients in China.

METHODS

We identified patients with first primary breast cancer diagnosed between January 1, 2016, and December 31, 2017, from 23 hospitals in 12 provinces in China. We analyzed the proportion of non-early-stage (stages II-IV) breast cancer cases based on the family history of breast cancer, body mass index (BMI), insurance status, and molecular subtypes. Multivariable analyses were used to estimate the factors associated with non-early-stage diagnosis among the molecular subtypes. We further compared these estimates with that in the United States using the Surveillance, Epidemiology, and End Results database.

RESULTS

A total of 9398 Chinese were identified with first primary invasive breast cancer. Of the 8767 patients with known stages, the human epidermal growth factor receptor 2 (HER2)-enriched subtype had the highest proportion of stages II-IV (76.6%) patients, followed by triple-negative breast cancer (73.2%), luminal B (69.9%), and luminal A (62.3%). The percentage of non-early-stage patients was higher in women with overweight or obesity than in those with a body mass index (BMI) <25 kg/m2 (adjusted odds ratio [OR] 1.3, 95% confidence interval (CI) 1.1-1.4). Patients with a family history of breast cancer had a higher likelihood of early-stage (adjusted OR 0.7, 0.5-0.8) breast cancer. Patients with rural insurance had a substantially higher risk of non-early-stage disease than those with urban insurance (adjusted OR 1.8, 1.4-2.2). Regarding the subtype, being overweight/obese only increased the risk of non-early-stage in luminal A breast cancer. Compared with the United States, China had a higher proportion of non-early-stage breast cancer for all subtypes, with the largest gap in luminal A (adjusted OR 2.2, 95% CI 2.0-2.4).

CONCLUSION

The wide disparities in stage at breast cancer diagnosis imply that China urgently needs to improve early breast cancer diagnosis and health equity.

Patient reported symptom burden amongst immigrant and Canadian long-term resident women undergoing breast cancer surgery

PURPOSE

Immigrants are susceptible to marginalization due to social isolation, economic disadvantage and systemic bias. Our goal was to compare symptom burden between immigrant and long-term resident women undergoing breast cancer surgery in Ontario, Canada.

METHODS

A population-level retrospective cohort-study using administrative databases was conducted. Women who underwent surgery for newly diagnosed breast cancer and were treated at regional cancer centers between 2010 and 2016 were included. The primary outcome was a moderate or severe (≥ 4) symptom score on the Edmonton Symptom Assessment System Scale (ESAS).

RESULTS

There were 12,250 (87.2%) long-term Canadian residents and 1,806(12.8%) immigrants. Immigrants were younger (mean age 53 vs. 61 years); had a higher proportion residing in a lowest income quintile neighbourhood (22.2% vs 15.4%); were less often on a primary-care physician roster (83.7% vs. 90.4%); and were less often diagnosed with Stage I/II disease (80.9% vs. 84.6%) (all p < 0.01). The proportion of women with scores ≥ 4 was significantly higher amongst immigrant women for 7/9 symptom categories; with the largest differences for depression (24.9% vs. 20.2%, p < 0.01) and pain (28.0% vs. 22.4%, p < 0.01). On multivariable regression analysis, immigration status was associated with scores ≥ 4 for pain (OR 1.13, 95% CI 1.02-1.23). There was an association between moderate/severe pain and region of origin, but not length of stay in Canada or immigration class.

CONCLUSIONS

This is the first study comparing symptom burden amongst immigrant and non-immigrant women with breast cancer at a population-level. Immigrant women with breast cancer undergoing surgery were found to have a higher burden of pain.

A comparative analysis of clinicopathological features and survival between pre and postmenopausal breast cancer from an Indian cohort

Breast cancer (BC) among premenopausal women is an aggressive disease associated with poor outcome despite intensive treatment. Higher burden is observed in southeast Asian countries attributed to younger population structure. We compared the reproductive and clinicopathological characteristics, distribution of subtypes and survival between pre and postmenopausal women from a retrospective cohort of BC patients with median follow up over 6 years to examine the differences. In our cohort of 446 BC patients, 162/446 (36.3%) were premenopausal. Parity and age at last childbirth were significantly different between pre and postmenopausal women. Premenopausal BC had a higher proportion of HER2 amplified and triple negative breast cancer (TNBC) tumors (p = 0.012). Stratified analysis by molecular subtypes showed TNBC had significantly better disease free (DFS) and overall survival (OS) among premenopausal group (mean survival, pre vs. post, DFS = 79.2 vs. 54.0 months, OS = 72.5 vs. 49.5 months, p = 0.002 for both). Analysis on external datasets (SCAN-B, METABRIC) confirmed this finding for overall survival. Our data confirmed the previously observed association of clinical and pathological features between pre and postmenopausal BC. Exploration of better survival among premenopausal TNBC tumors is warranted in larger cohorts with long term follow up.

Disaggregation of Asian American and Pacific Islander Women With Stage 0-II Breast Cancer Unmasks Disparities in Survival and Surgery-to-Radiation Intervals: A National Cancer Database Analysis From 2004 to 2017

PURPOSE

Aggregation of Asian Americans (AAs) with Native Hawaiians and Other Pacific Islanders (NHPIs) masks significant health disparities. We evaluated overall survival (OS) and surgery-to-radiation intervals (STRIs) among AA and NHPI women with early-stage breast cancer.

METHODS

This National Cancer Database study included women with stage 0-II breast cancer diagnosed between 2004 and 2017. STRI was defined as days from surgery to radiation. Patients were stratified by adjuvant treatment. AAs were disaggregated into geographically relevant subpopulations: East, South, and Southeast Asians. Kaplan-Meier estimates and log-rank tests assessed survival. Cox proportional hazard and linear regression were adjusted for clinical and sociodemographic factors.

RESULTS

In total, 578,927 women were included (median age 61 years, median follow-up 65 months, and 10-year OS 83%). AA and NHPI 10-year OS was 91% overall; subpopulation 10-year OS was 92% for East Asian, 90% for South Asian, 90% for Southeast Asian, and 83% for NHPI. On multivariable analysis, compared with non-Hispanic White, NHPI women had worse survival (adjusted hazard ratio [aHR] = 1.38; 95% CI, 1.09 to 1.77); all AA subpopulations had improved survival: East Asian (aHR = 0.57; 95% CI, 0.48 to 0.69), South Asian (aHR = 0.66; 95% CI, 0.51 to 0.84), and Southeast Asian (aHR = 0.78; 95% CI, 0.65 to 0.94). The AA and NHPI median STRI for was 73 days overall; the disaggregated median STRI was 68 days for East Asian, 80 days for South Asian, 77 days for Southeast Asians, and 81 days for NHPI. On adjusted analysis, compared with non-Hispanic White, Southeast Asians and NHPI had longer STRI by 6.6 (95% CI, 4.3 to 8.9) and 10.0 (95% CI, 5.8 to 14) days, respectively.

CONCLUSION

Breast cancer disparities exist among disaggregated AA and NHPI subpopulations. Data disaggregation insights may lead to interventions to overcome these disparities, such as optimizing time-to-treatment for select populations.