Racial disparities in female breast cancer in South Carolina: clinical evidence for a biological basis

COVID-19 challenges, responses, and resilience among rural Black women: a study protocol

Despite the aggregated burdens and challenges experienced by rural Black women during the COVID-19 pandemic, many likely also demonstrated strength and resilience to overcome challenges. A mixed methodology and a community-based participatory approach will be used to collect multilevel data on challenges, responses, resilience, and lessons during the pandemic from Black women, community health workers, and community leaders in rural areas in South Carolina (SC). Specifically, the unique circumstances and lived experiences of rural Black women during the COVID-19 pandemic will be documented to understand their needs regarding effective management of social, physical, and mental health challenges through focus group discussions and in-depth interviews with Black women, community health workers, and local community leaders recruited from rural SC communities. Barriers, facilitators, and potential impacts of multilevel resilience development will be identified through a survey administered among rural Black women recruited from 11 rural counties (with one as site for a pilot testing of the questionnaire). A report for public health practice will be developed, including recommended strategies to optimize health systems' emergency preparedness and responses through triangulation of qualitative and quantitative data from multiple sources. Findings in the proposed study will provide valuable references in terms of addressing social determinants of health factor challenges during the pandemic, fostering resilience, and informing evidence-based decision-making for policymakers. The study will contribute to the development of public health emergency preparedness plans, which can promote the resilience of women, their families, and local communities as well as optimize effective preparedness and response of health systems for rural Black women and their families during infectious disease outbreaks and other public health emergencies.

Elucidating the molecular signaling pathways of WAVE3

Cancer metastasis is a complex, multistep process that requires tumor cells to evade from the original site and form new tumors at a distant site or a different organ, often via bloodstream or the lymphatic system. Metastasis is responsible for more than 90% of cancer-related deaths. WAVE3 belongs to the Wiskott-Aldrich syndrome protein (WASP) family, which regulate actin cytoskeleton remodeling as well as several aspects of cell migration, invasion, and metastasis. In fact, WAVE3 has been established as a driver of tumor progression and metastasis in cancers from several origins, including triple negative breast cancers (TNBCs), which are classified as the most lethal subtype of breast cancer, due to their resistance to standard of care therapy and highly metastatic behavior. In this review, we will attempt to summarize the recent advances that have been made to understand how WAVE3 contributes to the molecular mechanisms that control cancer progression and metastasis. We will also review the signaling pathways that are involved in the regulation of WAVE3 expression and function to identify potential therapeutic options targeted against WAVE3 for the treatment of patients with metastatic tumors.

Effect of health disparities on overall survival of patients with glioblastoma

BACKGROUND

Examine the potential effects of health disparities in survival of glioblastoma (GB) patients.

METHODS

We conducted a retrospective chart review of newly diagnosed GB patients from 2000 to 2015 at a free standing dedicated cancer center (MD Anderson Cancer Center-MDACC) and a safety net county hospital (Ben Taub General Hospital-BT) located in Houston, Texas. We obtained demographics, insurance status, extent of resection, treatments, and other known prognostic variables (Karnofsky Score-KPS) to evaluate their role on overall GB survival (OS).

RESULTS

We identified 1073 GB patients consisting of 177 from BT and 896 from MDACC. We found significant differences by ethnicity, insurance status, KPS at diagnosis, extent of resection, and percentage of patients receiving standard of care (SOC) between the two centers. OS was 1.64 years for MDACC patients and 1.24 years for BT patients (p < 0.0176). Only 81 (45.8%) BT patients received SOC compared to 577 (64%) of MDACC patients (p < 0.0001). However, there was no significant difference in OS for patients who received SOC, 1.84 years for MDACC patients and 1.99 years for BT patients (p < 0.4787). Of the 96 BT patients who did not receive SOC, 29 (30%) had KPS less than 70 at time of diagnosis and 77 (80%) lacked insurance.

CONCLUSIONS

GB patients treated at a safety net county hospital had similar OS compared to a free standing comprehensive cancer center when receiving SOC. County hospital patients had poorer KPS at diagnosis and were often lacking health insurance affecting their ability to receive SOC.

Triple-Negative Breast Cancer: A Comparison of Race and Survival

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with a high prevalence in blacks. South Carolina demographically has a high percentage of blacks. This study examines survival and recurrence associated with TNBC in black and white women. A retrospective review of breast cancer patients within the Palmetto Health Cancer Registry was performed from 1999 to 2015. Patient demographics and tumor characteristics were collected and correlated with outcomes. Overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) were analyzed. The total number of breast cancer patients in the registry was 1723 (1085—white and 638—black). The median follow-up was 48.4 months. The majority of cancers diagnosed in both cohorts were early stage (I, IIA, IIB, 93.4% vs 90.4% P = NS). We identified 332 patients with TNBC. Of those 332 patients, 144 (43.4%) were whites and 188 (56.6%) were blacks. Older age (P = 0.01), high-grade (P < 0.001), and black race (P < 0.001) were significantly associated with TNBC on multivariate analysis. Five- and 10-year OS was significantly worse in blacks with TNBC (P < 0.001). There was no difference in DSS or RFS between the two cohorts. TNBC disproportionately affects black women and is an aggressive subtype of breast cancer with limited treatment options compared with receptor-positive breast cancer. Black patients with TNBC in our study had statistically worse OS. These findings are similar to what has been reported in the literature and prompts further research in newer targeted therapies.

Racial disparity in breast cancer: can it be mattered for prognosis and therapy

Breast cancer (BC) has emerged as a deadly disease that affects the lives of millions of women worldwide. It is the second leading cause of cancer-related deaths in the United States. Advancements in BC screening, preventive measures and treatment have resulted in significant decline in BC related deaths. However, unacceptable levels of racial disparity have been consistently reported, especially in African-American (AA) women compared to European American (EA). AA women go through worse prognosis, shorter survival time and higher mortality rates, despite higher cancer incidence reported in EA. These disparities are independent of socioeconomic status, access to healthcare or age, or even the stage of BC. Recent race-specific genetic and epigenetic studies have reported biological causes, which form the crux of this review. However, the developments are just the tip of the iceberg. Prioritizing primary research towards studying race-specific tumor microenvironment and biological composition of the host system in delineating the cause of these disparities is utmost necessary to ameliorate the disparity and design appropriate diagnosis/treatment regimen for AA women suffering from BC. In this review article, we discuss emerging trends and exciting discoveries that reveal how genetic/epigenetic circuitry contributed to racial disparity and discussed the strategies that may help in future therapeutic development.

A Population-Based Cross-Sectional Study Comparing Breast Cancer Stage at Diagnosis between Immigrant and Canadian-Born Women in Ontario

There is limited information on stage at breast cancer diagnosis in Canadian immigrant women. We compared stage at diagnosis between immigrant women and Canadian-born women, and determined whether ethnicity was an independent factor associated with stage. 41,213 women with invasive breast cancer from 2007 to 2012 were identified from the Ontario Cancer Registry. Women were classified as either immigrants or Canadian-born by linkage with the Immigration, Refugees, and Citizenship Canada's Permanent Resident database. Women's ethnicity was classified as Chinese, South Asian, or remaining women in Ontario. Logistic regression was performed to calculate the odds ratio (OR) of being diagnosed at stage I breast cancer (versus stage II-IV). 4,353 (10.6%) women were immigrants and 36,860 (89.4%) were Canadian-born women. The mean age at breast cancer diagnosis was 53.5 years for immigrants versus 62.3 years for Canadian-born women (p < 0.0001). Immigrant women were less likely than Canadian-born women to be diagnosed with stage I breast cancers (adjusted OR = 0.85; 95% CI: 0.79-0.91; p < 0.0001). The adjusted OR of being stage I was 1.28 (95% CI: 1.14-1.43; p < 0.0001) for women of Chinese ethnicity and was 0.82 (95% CI: 0.70-0.96; p = 0.01) for women of South Asian ethnicity, compared to the remaining women in Ontario. Canadian immigrant women were less likely than Canadian-born women to be diagnosed with early-stage breast cancers. Ethnicity was a greater contributor to the stage disparity than was immigrant status. South Asian women, regardless of immigration status, might benefit from increased breast cancer awareness programs.

Risk of Recurrence and Mortality in a Multi-Ethnic Breast Cancer Population

BACKGROUND

Compared to non-Hispanic whites, African-American women tend to be diagnosed with breast cancer at an earlier age, to have less favorable tumor characteristics, and to have poorer outcomes from breast cancer. The extent to which differences in clinical characteristics account for the black/white disparity in breast cancer mortality is unclear. The purpose of this investigation was to examine the association of clinical, demographic, and treatment variables with total mortality and breast cancer recurrence by race/ethnicity in a cohort of women diagnosed with invasive breast cancer.

METHODS

To this end, we used data on 3890 invasive breast cancer cases diagnosed at a single medical center. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) for the association of tumor characteristics and treatment variables with mortality and recurrence.

RESULTS

Compared to white women, black women with breast cancer presented with tumors that had worse prognostic factors, particularly higher stage, lower frequency of hormone-receptor positive tumors, and higher frequency of comorbidities. Hispanics also generally had less favorable prognostic factors compared to non-Hispanic whites. Among estrogen receptor-positive cases, blacks had roughly a two-fold increased risk of recurrence compared to non-Hispanic whites. However, ethnicity/race was not associated with total mortality. Tumor stage, tumor size, and Charlson comorbidity index were positively associated with mortality, and mammography and chemotherapy and hormone therapy were inversely associated with mortality.

CONCLUSION

In spite of poorer prognostic factors among blacks compared whites, race/ethnicity was not associated with total mortality in our study.

Cancer incidence, mortality, and stage at diagnosis in First Nations living in Manitoba

BACKGROUND

In the present study, we examined breast (bca) and colorectal cancer (crc) incidence and mortality and stage at diagnosis for First Nations (fn) individuals and all other Manitobans (aoms).

METHODS

Several population-based databases were linked to determine ethnicity and to calculate age-standardized incidence and mortality rates. Logistic regression was used to compare bca and crc stage at diagnosis.

RESULTS

From 1984-1988 to 2004-2008, the incidence of bca increased for fn and aom women. Breast cancer mortality increased for fn women and decreased for aom women. First Nations women were significantly more likely than aom women to be diagnosed at stages iii-iv than at stage i [odds ratio (or) for women ≤50 years of age: 3.11; 95% confidence limits (cl): 1.20, 8.06; or for women 50-69 years of age: 1.72; 95% cl: 1.03, 2.88). The incidence and mortality of crc increased for fn individuals, but decreased for aoms. First Nations status was not significantly associated with crc stage at diagnosis (or for stages i-ii compared with stages iii-iv: 0.98; 95% cl: 0.68, 1.41; or for stages i-iii compared with stage iv: 0.91; 95% cl: 0.59, 1.40).

CONCLUSIONS

Our results underscore the need for improved cancer screening participation and targeted initiatives that emphasis collaboration with fn communities to reduce barriers to screening and to promote healthy lifestyles.

Breast cancer survival disparity between African American and Caucasian women in Arkansas: A race-by-grade analysis

Despite progress in breast cancer treatment, disparity persists in survival time between African American (AA) and Caucasian women in the US. Tumor stage and tumor grade are the major prognostic factors that define tumor aggressiveness and contribute to racial disparity between AA and Caucasian women. Studying the interaction of race with tumor grade or stage may provide further insights into the role of intrinsic biological aggressiveness in disecting the AA-Caucasian survival disparity. Therefore, the current study was performed to evaluate the interaction of race with tumor grade and stage at diagnosis regarding survival in a cohort of patients treated at the Winthrop P. Rockefeller Cancer Institute of the University of Arkansas for Medical Sciences (Little Rock, AR, USA). The cohort included 1,077 patients, 208 (19.3%) AA and 869 (80.7%) Caucasian, diagnosed with breast cancer between January 1997 and December 2005. Kaplan-Meier survival plots were generated and Cox regressions were performed to analyze the associations of race with breast cancer-specific survival time. Over a mean follow-up time of 1.5 years, AA women displayed increased mortality risk due to breast cancer-specific causes [hazard ratio (HR), 1.74; 95% confidence interval (CI), 1.23–2.46]. The magnitude of racial disparity varied strongly with tumor grade (race-x-grade interaction; P<0.001). No significant interaction was observed between race and tumor stage or race and age at diagnosis. Among women diagnosed with grade I tumors, the race disparity in survival time after controlling for tumor stage and age was strong (HR, 9.07; 95% CI, 2.11–38.95), but no significant AA-Caucasian disparity was observed among women with higher-grade tumors. The data suggest that, when diagnosed with grade I breast cancer, AA may experience poorer survival outcomes compared with Caucasian patients, regardless of tumor stage or age. The findings potentially provide significant clinical and public health implications and justify further investigation.

Nomograms to estimate long-term overall survival and breast cancer-specific survival of patients with luminal breast cancer

Luminal breast cancer constitutes a group of highly heterogeneous diseases with a sustained high risk of late recurrence. We aimed to develop comprehensive and practical nomograms to better estimate the long-term survival of luminal breast cancer.Patients with luminal breast cancer diagnosed between 1990 and 2006 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database and randomly divided into the training (n = 87,867) and validation (n = 88,215) cohorts. The cumulative incidence function (CIF) and a competing-risks model were used to estimate the probability of breast cancer-specific survival (BCSS) and death from other causes. We integrated significant prognostic factors to build nomograms and subjected the nomograms to bootstrap internal validation and to external validation.We screened 176,082 luminal breast cancer cases. The 5- and 10-year probabilities of overall death were 0.089 and 0.202, respectively. The 5- and 10-year probabilities of breast cancer-specific mortality (BCSM) were 0.053 and 0.112, respectively. Nine independent prognostic factors for both OS and BCSS were integrated to construct the nomograms. The calibration curves for the probabilities of 5- and 10-year OS and BCSS showed excellent agreement between the nomogram prediction and actual observation. The C-indexes of the nomograms were high in both internal validation (0.732 for OS and 0.800 for BCSS) and external validation (0.731 for OS and 0.794 for BCSS).We established nomograms that accurately predict OS and BCSS for patients with luminal breast cancer. The nomograms can identify patients with higher risk of late overall mortality and BCSM, helping physicians in facilitating individualized treatment.

Patterns of axillary lymph node metastases and recurrent disease in grade 1 breast cancer in a New Zealand cohort: Does ethnicity matter?

BACKGROUND

In New Zealand, Māori and Pacific women are more likely than New Zealand/European women to present at a younger age with larger tumours and metastatic disease. Survival rates are also differential by ethnicity. Many factors are believed to be responsible for this including differences in comorbidities, delays to presentation and delays in treatment. It is unclear whether these differences exist amongst women with grade 1 cancer in New Zealand. Therefore, we examined patterns of axillary nodal involvement, recurrent disease and mortality in grade 1 breast cancer in New Zealand women, and whether ethnicity was an important predictor for any of these outcomes.

METHOD

Data was retrieved from the Auckland Breast Cancer Registry (ABCR) and the Waikato Breast Cancer Registry (WBCR) which are prospective, population-based databases. All women newly diagnosed with grade 1 primary invasive breast cancer between 1 June 2000 and 31 May 2013 were identified from the two registries.

RESULTS

There were 2857 grade 1 breast cancers diagnosed over this time period. Axillary lymph nodes were involved in 19.0% of women, and 5.1% developed recurrent disease (locoregional or distant). Pacific and Māori women were more likely than NZ European women to have larger tumours and lymphovascular invasion (LVI). Predictors for axillary node involvement were tumour size greater than 10mm, LVI and non-screen detected cancers. Tumour size greater than 10mm, lobular carcinoma and BCS without radiotherapy were predictive of recurrent and or metastatic disease. Ethnicity was not observed to be an independent predictor for axillary nodal involvement, recurrent and/or metastatic disease, or breast cancer specific mortality amongst New Zealand women with grade 1 breast cancer.

CONCLUSION

Ethnicity was not a predictor of axillary node involvement, recurrent disease or mortality in grade 1 breast cancer in our population.

How do integrated health care systems address racial and ethnic disparities in colon cancer?

PURPOSE

Colorectal cancer (CRC) disparities have persisted over the last two decades. CRC is a complex disease requiring multidisciplinary care from specialists who may be geographically separated. Few studies have assessed the association between integrated health care system (IHS) CRC care quality, survival, and disparities. The purpose of this study was to determine if exposure to an IHS positively affects quality of care, risk of mortality, and disparities.

PATIENTS AND METHODS

This retrospective secondary-data analysis study, using the California Cancer Registry linked to state discharge abstracts of patients treated for colon cancer (2001 to 2006), compared the rates of National Comprehensive Cancer Network (NCCN) guideline-based care, the hazard of mortality, and racial/ethnic disparities in an IHS versus other settings.

RESULTS

More than 30,000 patient records were evaluated. The IHS had overall higher rates of adherence to NCCN guidelines. Propensity score-matched Cox models showed an independent and protective association between care in the IHS and survival (hazard ratio [HR], 0.87; 95% CI, 0.85 to 0.90). This advantage persisted across stage groups. Black race was associated with increased hazard of mortality in all other settings (HR, 1.15; 95% CI, 1.04 to 1.27); however, there was no disparity within the IHS for any minority group (P > .11 for all groups) when compared with white race.

CONCLUSION

The IHS delivered higher rates of evidence-based care and was associated with lower 5-year mortality. Racial/ethnic disparities in survival were absent in the IHS. Integrated systems may serve as the cornerstone for developing accountable care organizations poised to improve cancer outcomes and eliminate disparities under health care reform.

Long-term outcomes among African-American and white women with breast cancer: what is the impact of comorbidity?

OBJECTIVES

We examined the association between comorbidity and long-term mortality from breast cancer and other causes among African-American and white women with breast cancer.

METHODS

A total of 170 African-American and 829 white women aged 40-84years were followed for up to 28years with median follow-up of 11.3years in the Health and Functioning in Women (HFW) study. The impact of the Charlson Comorbidity Score (CCS) in the first few months following breast cancer diagnosis on the risk of mortality from breast cancer and other causes was examined using extended Cox models.

RESULTS

Median follow-up was significantly shorter for African-American women than their white counterparts (median 8.5years vs. 12.3years). Compared to white women, African-American women had significantly fewer years of education, greater body mass index, were more likely to have functional limitations and later stage at breast cancer diagnosis, and fewer had adequate financial resources (all P<0.05). Proportionately more African-American women died of breast cancer than white women (37.1% vs. 31.4%, P=0.15). A positive and statistically significant time-varying effect of the Charlson Comorbidity Score (CCS) on other-cause mortality persisted throughout the first 5years of follow-up (P<0.001) but not for its remainder.

CONCLUSIONS

Higher CCS was associated with increased risk of other-cause mortality, but not breast cancer specific mortality; the association did not differ among African-American and white women.

Genetic variants in microRNAs and breast cancer risk in African American and European American women

MicroRNAs (miRNAs) are an integral part of the post-transcriptional machinery of gene expression and have been implicated in the carcinogenic cascade. Single nucleotide polymorphisms (SNPs) in miRNAs and risk of breast cancer have been evaluated in populations of European or Asian ancestry, but not among women of African ancestry. Here we examined 145 SNPs in six miRNA processing genes and in 78 miRNAs which target genes known to be important in breast cancer among 906 African American (AA) and 653 European American (EA) cases and controls enrolled in the Women's Circle of Health Study. Allele frequencies of most SNPs (87 %) differed significantly by race. We found a number of SNPs in miRNAs and processing genes in association with breast cancer overall or stratified by estrogen receptor (ER) status. Several associations were significantly different by race, with none of the associations being significant in both races. Using a polygenic risk score to combine the effects of multiple SNPs, we found significant associations with the score in each subgroup analysis. For ER-positive cancer, each unit increment of the risk score was associated with a 51 % increased risk in AAs (OR = 1.51, 95 % CI = 1.30-1.74, p = 3.3 × 10(-8)) and a 73 % increased risk in EAs (OR = 1.73, 95 % CI = 1.45-2.06, p = 1.4 × 10(-9)). These data show, for the first time, that miRNA-related genetic variations may underlie the etiology of breast cancer in both populations of African and European ancestries. Future studies are needed to validate our findings and to explore the underlying mechanisms.

Mind the gap: racial differences in breast cancer incidence and biologic phenotype, but not stage, among low-income women participating in a government-funded screening program

Breast cancer mortality rates in South Carolina (SC) are 40 % higher among African-American (AA) than European-American (EA) women. Proposed reasons include race-associated variations in care and/or tumor characteristics, which may be subject to income effects. We evaluated race-associated differences in tumor biologic phenotype and stage among low-income participants in a government-funded screening program. Best Chance Network (BCN) data were linked with the SC Central Cancer Registry. Characteristics of breast cancers diagnosed in BCN participants aged 47-64 years during 1996-2006 were abstracted. Race-specific case proportions and incidence rates based on estrogen receptor (ER) status and histologic grade were estimated. Among 33,880 low-income women accessing BCN services, repeat breast cancer screening utilization was poor, especially among EAs. Proportionally, stage at diagnosis did not differ by race (607 cancers, 53 % among AAs), with about 40 % advanced stage. Compared to EAs, invasive tumors in AAs were 67 % more likely (proportions) to be of poor-prognosis phenotype (both ER-negative and high-grade); this was more a result of the 46 % lesser AA incidence (rates) of better-prognosis (ER+ lower-grade) cancer than the 32 % greater incidence of poor-prognosis disease (p values <0.01). When compared to the general SC population, racial disparities in poor-prognostic features within the BCN population were attenuated; this was due to more frequent adverse tumor features in EAs rather than improvements for AAs. Among low-income women in SC, closing the breast cancer racial and income mortality gaps will require improved early diagnosis, addressing causes of racial differences in tumor biology, and improved care for cancers of poor-prognosis biology.

Relationship between tumor DNA methylation status and patient characteristics in African-American and European-American women with breast cancer

Aberrant DNA methylation is critical for development and progression of breast cancer. We investigated the association of CpG island methylation in candidate genes and clinicopathological features in 65 African-American (AA) and European-American (EA) breast cancer patients. Quantitative methylation analysis was carried out on bisulfite modified genomic DNA and sequencing (pyrosequencing) for promoter CpG islands of p16, ESR1, RASSF1A, RARβ2, CDH13, HIN1, SFRP1 genes and the LINE1 repetitive element using matched paired non-cancerous and breast tumor specimen (32 AA and 33 EA women). Five of the genes, all known tumor suppressor genes (RASSF1A, RARβ2, CDH13, HIN1 and SFRP1), were found to be frequently hypermethylated in breast tumor tissues but not in the adjacent non-cancerous tissues. Significant differences in the CDH13 methylation status were observed by comparing DNA methylation between AA and EA patients, with more obvious CDH13 methylation differences between the two patient groups in the ER- disease and among young patients (age<50). In addition, we observed associations between CDH13, SFRP1, and RASSF1A methylation and breast cancer subtypes and between SFRP1 methylation and patient's age. Furthermore, tumors that received neoadjuvant therapy tended to have reduced RASSF1A methylation when compared with chemotherapy naïve tumors. Finally, Kaplan Meier survival analysis showed a significant association between methylation at 3 loci (RASSF1A, RARβ2 and CDH13) and reduced overall disease survival. In conclusion, the DNA methylation status of breast tumors was found to be significantly associated with clinicopathological features and race/ethnicity of the patients.

Racial disparities in breast cancer mortality in a multiethnic cohort in the Southeast

BACKGROUND

Although much has been done to examine those factors associated with higher mortality among African American women, there is a paucity of literature that examines disparities among rural African Americans in South Carolina. The purpose of this investigation was to examine the association of race and mortality among breast cancer patients in a large cohort residing in South Carolina for which treatment regimens are standardized for all patients.

METHODS

Subjects included 1209 women diagnosed with breast cancer between 2000 and 2002 at a large, local hospital containing a comprehensive breast center. Kaplan-Meier survival curves were calculated to determine survival rates among African American and European American women, stratified by disease stage or other prognostic characteristics. Adjusting for various characteristics, Cox multivariate survival models were used to estimate the hazard ratio (HR).

RESULTS

The 5-year overall all-cause mortality survival proportion was ∼78% for African American women and ∼89% for European American women, P < 0.01. In analyses of subpopulations of women with identical disease characteristics, African American women had significantly higher mortality than European American women for the same type of breast cancer disease. In multivariate models, African American women had significantly higher mortality than European American women for both breast cancer-specific death (HR, 2.41; 95% confidence interval [CI], 1.21-4.79) and all-cause mortality (HR, 1.42; 95% CI, 1.06-1.89).

CONCLUSIONS

African American women residing in rural South Carolina had lower survival for breast cancer even after adjustment for disease-related prognostic characteristics. These findings support health interventions among African American breast cancer patients aimed at tertiary prevention strategies or further down-staging of disease at diagnosis.

Ethnic differences in breast cancer survival: status and determinants

Ethnic differences in breast cancer survival have been a long-standing concern. The objective of this article is to present relevant studies for all major US racial/ethnic groups including African-Americans, Latinos, Native Americans, Japanese-Americans and Native Hawaiians, and to discuss underlying causes of disparity. In comparison to Caucasian women, African-American women continue to experience the poorest breast cancer-specific survival of all ethnic groups in the USA. The prognosis for Latinos, Native Hawaiians and Native Americans is intermediate, better than for African-Americans but not as good as for Caucasians, whereas Japanese-American women tend to have better outcomes. The following possible contributors to the observed differences are discussed in detail: unfavorable distribution of stage at diagnosis due to low screening rates, limited access to care and treatment, tumor type, comorbidities, socioeconomic status, obesity and physical activity.

PKCα and ERβ Are Associated with Triple-Negative Breast Cancers in African American and Caucasian Patients

Although the incidence of breast cancer in the United States is higher in Caucasian women compared with African American women, African-American patients have more aggressive disease as characterized by a higher percentage of triple-negative breast cancers (TNBCs), high-grade tumors, and a higher mortality rate. PKCα is a biomarker associated with endocrine resistance and poor prognosis and ERβ is emerging as a protective biomarker. Immunohistochemical analysis of ERβ and PKCα expression was performed on 198 formalin-fixed paraffin-embedded primary infiltrating ductal carcinomas from 105 African-American and 93 Caucasian patients. PKCα is positively correlated with TNBC in patients of both races and with high tumor grade in African-American patients. Patients with TNBC express less nuclear ERβ compared with all other subtypes. We find no difference in frequency or intensity of PKCα or ERβ expression between African-American and Caucasian patients. PKCα and ERβ are discussed as potential therapeutic targets for the treatment of patients with TNBC.

The racial disparity in breast cancer mortality

Black women die of breast cancer at a much higher rate than white women. Recent studies have suggested that this racial disparity might be even greater in Chicago than the country as a whole. When data describing this racial disparity are presented they are sometimes attributed in part to racial differences in tumor biology. Vital records data were employed to calculate age-adjusted breast cancer mortality rates for women in Chicago, New York City and the United States from 1980-2005. Race-specific rate ratios were used to measure the disparity in breast cancer mortality. Breast cancer mortality rates by race are the main outcome. In all three geographies the rate ratios were approximately equal in 1980 and stayed that way until the early 1990s, when the white rates started to decline while the black rates remained rather constant. By 2005 the black:white rate ratio was 1.36 in NYC, 1.38 in the US, and 1.98 in Chicago. In any number of ways these data are inconsistent with the notion that the disparity in black:white breast cancer mortality rates is a function of differential biology. Three societal hypotheses are posited that may explain this disparity. All three are actionable, beginning today.

Bodyweight and other correlates of symptom-detected breast cancers in a population offered screening

OBJECTIVE

To determine the factors associated with symptom-detected breast cancers in a population offered screening.

METHODS

We interviewed 1,459 Australian women aged 40-69, 946 with symptom-detected and 513 with mammogram-detected invasive breast cancers ≥ 1.1 cm in diameter about their personal, mammogram, and breast histories before diagnosis and reviewed medical records for tumor characteristics and mammogram dates, calculating ORs and 95% confidence intervals (CIs) for symptom- versus mammogram-detected cancers in logistic regression models.

RESULTS

Lack of regular mammograms (<2 mammograms in the 4.5 years before diagnosis) was the strongest correlate of symptom-detected breast cancer (OR = 3.04 for irregular or no mammograms). In women who had regular mammograms (≥ 2 mammograms in the 4.5 years before diagnosis), the independent correlates of symptom-detected cancers were low BMI (OR < 25 kg/m(2) vs. ≥ 30 kg/m(2) = 2.18, 95% CI 1.23-3.84; p = 0.008), increased breast density (available in 498 women) (OR highest quarter vs. lowest = 3.50, 95% CI 1.76-6.97; p (trend) = 0.004), high-grade cancer, and a larger cancer (each p < 0.01). In women who did not have regular mammograms, the independent correlates were age <50 years, a first cancer, and a ≥ 2-cm cancer. Smoking appeared to modify the association of symptom-detected cancer with low BMI (higher ORs for low BMI in current smokers) and estrogen receptor (ER) status (higher ORs for low BMI in ER cancers).

CONCLUSION

Women with low BMI may benefit from a tailored approach to breast cancer detection, particularly if they smoke.

The role of the basal stem cell of the human breast in normal development and cancer

MCF-10F, an ERα negative human breast epithelial cell line derived from normal breast tissue, is able to form ductal structures in a tridimensional collagen matrix system. MCF-10F cells that are estrogen transformed (trMCF cells) progressively express phenotypes of in vitro cell transformation, including colony formation in agar methocel and loss of the ductulogenic capacity. Selection of these trMCF cells for invasiveness identified cells (bcMCF) that formed tumors in severe combined immunodeficient mice. The cell lines derived from those tumors (caMCF) were poorly differentiated ER, PR, and ERBB2 negative adenocarcinomas. These characteristics are similar to the human basal cell-like carcinomas. This in vitro-in vivo model demonstrates the importance of the basal cell type as a stem cell that reconstitutes the branching pattern of the breast and that is also target of a carcinogenic insult leading to transformation and cancer.

A profile of prognostic and molecular factors in European and Māori breast cancer patients

Background

New Zealand Māori have a poorer outcome from breast cancer than non-Māori, yet prognostic data are sparse. The objective of this study was to quantify levels of prognostic factors in a cohort of self-declared Māori and European breast cancer patients from Christchurch, New Zealand.

Methods and Results

Clinicopathological and survival data from 337 consecutive breast cancer patients (27 Māori, 310 European) were evaluated. Fewer tumours were high grade in Māori women than European women (p = 0.027). No significant ethnic differences were detected for node status, tumour type, tumour size, human epidermal growth factor receptor, oestrogen and progesterone receptor (ER/PR) status, or survival.

In addition, tumour and serum samples from a sub-cohort of 14 Māori matched to 14 NZ European patients were analyzed by immunohistochemistry and enzyme linked immunosorbent assay for molecular prognostic factors. Significant correlations were detected between increased grade and increased levels of hypoxia inducible factor-1 (HIF-1α), glucose transporter-1 (GLUT-1), microvessel density (MVD) and cytokeratins CK5/6 (p < 0.05). High nodal status correlated with reduced carbonic anhydrase IX (CA-IX). Negative ER/PR status correlated with increased GLUT-1, CA-IX and MVD. Within the molecular factors, increased HIF-1α correlated with raised GLUT-1, MVD and CK5/6, and CK5/6 with GLUT-1 and MVD (p < 0.05). The small number of patients in this sub-cohort limited discrimination of ethnic differences.

Conclusions

In this Christchurch cohort of breast cancer patients, Māori women were no more likely than European women to have pathological or molecular factors predictive of poor prognosis. These data contrast with data from the North Island NZ, and suggest potential regional differences.

Racial differences in follow-up of abnormal mammography findings among economically disadvantaged women

BACKGROUND

In the United States, and particularly in South Carolina, African-American women suffer disproportionately higher mortality rates from breast cancer than European-American women. The timeliness of patient adherence to the follow-up of mammographic abnormalities may influence prognosis and survival. The objective of the current investigation was to examine racial differences in the completion and completion time of a diagnostic workup after the finding of a suspicious breast abnormality.

METHODS

Study participants of the Best Chance Network, a statewide service program that provides free mammography screening to economically disadvantaged and medically underserved women, were included in the study. Racial differences in tumor characteristics and adherence to recommended workup were tested using chi-square tests and t tests. Logistic and Cox regression modeling was used to assess the relation between workup completion and other factors among African-American women and European-American women.

RESULTS

Completion of the workup was associated with the number of previous procedures and income, and no significant differences were noted by race. The amount of time to completion of the workup was influenced by previous procedures, income, and race. After accounting for completion time, African-American women were 12% less likely than European-American women to complete the recommended workup (hazard ratio, 0.88; P=.01).

CONCLUSIONS

The results from this study established a racial disparity in the time to completion of a diagnostic workup among Best Chance Network participants. These findings highlight the importance of understanding the factors associated with delays in and adherence to completing the recommended workup when breast abnormalities are detected in mammograms.

Estrogen induced breast cancer is the result in the disruption of the asymmetric cell division of the stem cell

There is evidence that in the human breast there is a stem cell population that can give rise to many different cell types and have the unique potential to divide asymmetrically. In this way stem cells maintain the stem cell pool and simultaneously generate committed cells that reconstitute the organ for example for preparing the breast for a new pregnancy after the involution from a previous pregnancy and lactation process. In addition to the in vivo models of mammary morphogenesis there are in vitro systems that are more amenable to study in critically determined conditions the ductulogenic pattern of growth of the breast epithelia. Primary mammary epithelial cells grown in collagen matrix are able to form tree-like structures resembling in vivo ductulogenesis. The human breast epithelial cells MCF-10F formed tubules when grown in type I collagen and we demonstrated that treatment of these cells with 17β-estradiol (E(2)) induces phonotypical changes indicative of neoplastic transformation. The transformation of MCF-10F by E(2) is associated with impaired ductal morphogenesis by altering the stem cells unique potential to divide asymmetrically inducing formation of solid masses mimicking intraductal carcinoma that progress to invasive and tumorigenic phenotype. In the present work we present evidence for the mechanism of cell asymmetry leading to normal ductulogenesis and how the normal stem cell is transformed to cancer stem cell by altering this process. Furthermore, we demonstrate that the carcinogenic agent, in this case E(2), induces a defect in the asymmetric cell division program of the normal mammary stem cell.

Racial differences in the incidence of breast cancer subtypes defined by combined histologic grade and hormone receptor status

Breast cancer encompasses several distinct clinical entities of very different characteristics and behaviors, a fact which likely contributes to the higher breast cancer mortality in African-Americans (AA) despite the higher incidence in European-Americans (EA). We are interested in how incidence variability in cancer subtypes defined by combined estrogen receptor (ER) and grade contributes to racial mortality disparities. As an initial step, we compared age-specific and age-adjusted incidence rates for each ER/Grade subtype in South Carolina (SC-a southern state) with Ohio (a northern mid-western state), using state registry data for 1996-2004. Each ER/Grade subtype had a distinct incidence pattern and rate, with three striking racial/geographic differences. First, the racial incidence disparity in ER negative (ER-) cancers was mostly within the ER-/G3 subtype, of which AAs had ~65% higher incidence than did EAs; ER-/G2 was much less common, but of significantly higher incidence in AAs. Second, the racial disparity in ER positive (ER+) cancers was in the ER+/lower-grade cancers, with a marked EA excess in both states. Third, AA incidence of the ER+/lower-grade subtypes was ~26% higher in Ohio than in SC. The other subtypes (ER-/G1 and ER+/G3) varied minimally by race and state, and the latter showed a strong association with age. Age adjustment halved the racial difference in mean age at diagnosis to about 2 years younger in AAs, compared to 4 years younger in case comparisons. Use of age-adjusted and age-specific rates of breast cancer subtypes may improve understanding of racial incidence and mortality disparities over time and geography. This approach also may aid in estimating the race-specific incidence rates of triple-negative breast cancer.

An admixture scan in 1,484 African American women with breast cancer

African American women with breast cancer present more commonly with aggressive tumors that do not express the estrogen receptor (ER) and progesterone receptor (PR) compared with European American women. Whether this disparity is the result of inherited factors has not been established. We did an admixture-based genome-wide scan to search for risk alleles for breast cancer that are highly differentiated in frequency between African American and European American women, and may contribute to specific breast cancer phenotypes, such as ER-negative (ER-) disease. African American women with invasive breast cancer (n = 1,484) were pooled from six population-based studies and typed at approximately 1,500 ancestry-informative markers. We investigated global genetic ancestry and did a whole genome admixture scan searching for breast cancer-predisposing loci in association with disease phenotypes. We found a significant difference in ancestry between ER+PR+ and ER-PR- women, with higher European ancestry among ER+PR+ individuals, after controlling for possible confounders (odds ratios for a 0 to 1 change in European ancestry proportion, 2.84; 95% confidence interval, 1.13-7.14; P = 0.026). Women with localized tumors had higher European ancestry than women with non-localized tumors (odds ratios, 2.65; 95% confidence interval, 1.11-6.35; P = 0.029). No genome-wide statistically significant associations were observed between European or African ancestry at any specific locus and breast cancer, or in analyses stratified by ER/PR status, stage, or grade. In summary, in African American women, genetic ancestry is associated with ER/PR status and disease stage. However, we found little evidence that genetic ancestry at any one region contributes significantly to breast cancer risk or hormone receptor status.

Hospital factors and racial disparities in mortality after surgery for breast and colon cancer

PURPOSE

Black patients have worse prognoses than whites with breast or colorectal cancer. Mechanisms underlying such disparities have not been fully explored. We examined the role of hospital factors in racial differences in late mortality after surgery for breast or colon cancer.

METHODS

Patients undergoing surgery after new diagnosis of breast or colon cancer were identified using the Surveillance Epidemiology and End Results-Medicare linked database (1995 to 2005). The main outcome measure was mortality at 5 years. Proportional hazards models were used to assess relationships between race and late mortality, accounting for patient factors, socioeconomic measures, and hospital factors. Fixed and random effects models were used to account for quality differences across hospitals.

RESULTS

Black patients, compared with white patients, had lower 5-year overall survival rates after surgery for breast (62.1% v 70.4%, respectively; P < .001) and colon cancer (41.3% v 45.4%, respectively; P < .001). After controlling for age, comorbidity, and stage, black race remained an independent predictor of mortality for breast (adjusted hazard ratio [HR] = 1.25; 95% CI, 1.16 to 1.34) and colon cancer (adjusted HR = 1.13; 95% CI, 1.07 to 1.19). After risk adjustment, hospital factors explained 36% and 54% of the excess mortality for black patients with breast cancer and colon cancer, respectively. Hospitals with large minority populations had higher late mortality rates independent of race.

CONCLUSION

Hospital factors, including quality, are important mediators of the association between race and mortality for breast and colon cancer. Hospital-level quality improvement should be a major component of efforts to reduce disparities in cancer outcomes.

Vernonia amygdalina: anticancer activity, authentication, and adulteration detection

Evidence suggests that most chemotherapeutic agents are less effective as treatment in patients with estrogen receptor-negative (ER-) breast carcinomas compared to those with estrogen receptor-positive (ER+) breast carcinomas. Moreover, African American Women (AAW) is disproportionately diagnosed with ER- breast cancer compared to their white counterparts. Novel therapies effective against ER- breast carcinomas are urgently needed to ameliorate the health disparity. Previous reports show that low concentrations (microgram/ml) of water-soluble leaf extracts of a Nigerian edible plant, V. amygdalina (VA), potently retards the proliferative activities of ER+ human breast cancerous cells (MCF-7) in vitro in a concentration-dependent fashion. However, the anti-proliferative activities of VA in either ductal or ER- carcinoma cells have not been characterized. The exposure of BT-549 to increasing concentrations of VA (10, 100, and 1000 microg/mL) inhibited cell growth by approximately 14 % (P<0.05), 22 % (p<0.05), and 50 % (p<0.005) respectively. The cell count studies were corroborated by DNA synthesis studies. Treatments of BT-549 with 10, 100, and 1000 microg/mL VA inhibited DNA synthesis in a concentration dependent fashion by 22 %, 76 % (P<0.05), and 86 % (p<0.01) respectively. BT-549 cells were insensitive to 10 and 100 nM paclitaxel (TAX) treatments. Isolation of DNA from dried VA leaves yielded approximately 12.2 and 1 kbp genomic DNA that were Eco RI-insensitive but Hind III and Bam HI-sensitive. These pieces of information may be used to enhance the safety of medicinal botanical VA through authentication, and adulteration detection.

Tamoxifen chemoprevention treatment and time to first diagnosis of estrogen receptor-negative breast cancer

BACKGROUND

Tamoxifen's effect of reducing the risk of estrogen receptor (ER)-positive breast cancer is well established. Its effect on the time to first diagnosis of breast cancer has not been reported. We used information from the randomized, placebo-controlled Breast Cancer Prevention Trial (BCPT) to make that evaluation.

METHODS

A total of 13,388 women enrolled in BCPT, of whom 174 were diagnosed with ER-positive tumors and 69 were diagnosed with ER-negative tumors. A flexible semiparametric cure rate model was used to assess the effects of tamoxifen vs placebo treatment on the time to disease diagnosis. Multivariable logistic regression, adjusted for age and tumor size at diagnosis, was used to assess the association between the mammography detection rate and treatment with tamoxifen. All statistical tests were two-sided.

RESULTS

The median times to diagnosis of ER-positive tumors were similar in both treatment groups (43 months for the placebo arm and 51 months for the treatment arm). Times to diagnosis of ER-negative tumors, however, differed between treatment groups, with median times to diagnosis of 36 months in the placebo arm vs 24 months in the tamoxifen arm (difference = 12 months, 95% confidence interval [CI] = 3 to 17 months, P = .037). ER-negative breast cancers in the tamoxifen arm were more likely than those in the placebo arm to be detected by mammography than by clinical breast examination alone after adjustment for age and tumor size, but the increase was only marginally statistically significant (odds ratio for mammography detection = 4.68, 95% CI = 0.86 to 25.32, P = .073). No differences were found in the mammography detection rates for ER-positive tumors by treatment arm.

CONCLUSION

Although tamoxifen treatment does not reduce the incidence of ER-negative breast cancer, it may have advanced detection of such tumors by approximately 1 year, compared with that in the placebo arm. The time to diagnosis of ER-positive breast cancer was similar in both treatment arms.

Breast cancer survival among economically disadvantaged women: the influences of delayed diagnosis and treatment on mortality

Breast cancer affects thousands each year in the United States, and disproportionately affects certain subgroups. For example, the incidence of breast cancer in South Carolina is lower in African American compared with European American women by approximately 12% to 15%, but their mortality rate is twice as high as in European American women. The purpose of the study was to assess factors associated with breast cancer mortality between African American and European American women. Participants (n=314) in South Carolina's Breast and Cervical Cancer Early Detection Program (SCBCCEDP), which provides breast cancer screening and treatment services, during the years 1996-2004 were included in the study. Data, including tumor characteristics, delay intervals, and race, were examined using the chi(2) test and the Wilcoxon rank-sum test. Cox regression modeling was used to assess the relationship between delay intervals and other factors. No racial differences were found in age at diagnosis, tumor characteristics, or delay intervals. Time delay intervals did not explain differences and mortality rates by race. Survival, however, was affected by prognostic factors as well as by a significant interaction between hormone-receptor status and race. Despite the excellent record of the SCBCCEDP in screening and diagnostic or treatment referrals, the racial disparities in breast cancer mortality continue to exist in South Carolina. These findings highlight the need for future research into the etiology of racial differences, and their impact on breast cancer survival.

Race/ethnicity and breast cancer estrogen receptor status: impact of class, missing data, and modeling assumptions

OBJECTIVE

To test whether reported associations between race/ethnicity and breast cancer estrogen receptor (ER) status are inflated due to missing ER data, lack of socioeconomic data, and use of the odds ratio (OR) rather than the prevalence ratio (PR).

METHODS

We geocoded and added census tract socioeconomic data to all cases of primary invasive breast cancer (n = 42,420) among women diagnosed between 1998 and 2002 in two California cancer registries (San Francisco Bay Area; Los Angeles County) and analyzed the data using log binomial regression.

RESULTS

Adjusting for socioeconomic position and tumor characteristics, in models using the imputed data, reduced the PR for the black versus white excess risk of being ER--from 1.76 (95% CI: 1.66, 1.86; adjusted for age and catchment area) to 1.47 (95% CI: 1.38, 1.56). The latter parameter estimate was 16% greater (i.e., 1.56) in models excluding women with missing ER data, and was 43% greater when estimated using the OR (i.e., 1.82).

CONCLUSION(S)

Studies on race/ethnicity and ER status that fail to account for missing data and socioeconomic data and report the OR are likely to yield inflated estimates of racial/ethnic disparities in ER status.

Identification of UDP-glucuronosyltransferase 1A10 in non-malignant and malignant human breast tissues

UGT1A10 was recently identified as the major isoform that conjugates estrogens. In this study, real-time PCR revealed high levels of UGT1A10 and UGT2B7 mRNA in human breast tissues. The expression of UGT1A10 in breast was a novel finding. UGT1A10 and UGT2B7 mRNAs were differentially expressed among normal and malignant specimens. Their overall expression was significantly decreased in breast carcinomas as compared to normal breast specimens (UGT1A10: 68+/-26 vs. 252+/-86, respectively; p<0.05) and (UGT2B7: 1.4+/-0.7 vs. 12+/-4, respectively; p<0.05). Interestingly, in African American women, UGT1A10 expression was significantly decreased in breast carcinomas in comparison to normals (57+/-35 vs. 397+/-152, respectively; p<0.05). Among Caucasian women, UGT2B7 was significantly decreased in breast carcinomas in comparison to normals (1.1+/-0.5 vs. 13.5+/-6, respectively; p<0.05). Glucuronidation of 4-hydroxylated estrone (4-OHE(1)) was significantly reduced in breast carcinomas compared to normals (30+/-15 vs. 106+/-31, respectively; p<0.05). Differential down-regulation of UGT1A10 and UGT2B7 mRNAs, protein, and activity in breast carcinomas compared to the adjacent normal breast specimens from the same donor were also found. These data illustrate the novel finding of UGT1A10 in human breast and confirm the expression of UGT2B7. Significant individual variation and down-regulation of expression in breast carcinomas of both isoforms were also demonstrated. These findings provide evidence that decreased UGT expression and activity could result in the promotion of carcinogenesis.

Population differences in breast cancer severity

Breast cancer incidence and mortality vary among different populations. African-American, Hispanic, Asian and Native American women have lower incidence but higher mortality compared with non-Hispanic white women. Explanations for the observed variation include social and economic factors such as education, income level, health insurance coverage, use of mammography, parity, breastfeeding and diet. Breast cancer may be a heterogeneous disease with different subtypes of tumors having different genetic and environmental risk factors. The difference in frequency of particular tumor subtypes between populations may explain some of the differences in incidence and mortality. Known genetic variants explain a small fraction of breast cancer cases, and so far there are no susceptibility genes that explain population differences in incidence and mortality. Studies evaluating the risk for particular tumor subtypes combining genetic and environmental variables and analyzing cases from different populations are needed to understand population differences in the severity of breast cancer.

The role of human epidermal growth factor receptor 2 in the survival of women with estrogen and progesterone receptor-negative, invasive breast cancer: the California Cancer Registry, 1999-2004

BACKGROUND

Breast cancers that are negative for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) (triple negative [TN]) have been associated with high-grade histology, aggressive clinical behavior, and poor survival. It has been determined that breast cancers that are negative for ER and PR but positive for HER2 (double negative [DN]) share features with TN breast cancers. In this report, the authors quantified the contribution of HER2 as well as demographic and tumor characteristics to the survival of women with TN tumors, DN tumors, and other breast cancers (OBC).

METHODS

In total, 61,309 women who were diagnosed with invasive breast cancer between 1999-2004 were identified in the California Cancer Registry. Demographic and tumor characteristics of women with TN tumors were compared with those from women with DN tumors and women with OBC. A compound proportional hazards regression analysis (PHPH) (a generalization of the Cox proportional hazards model) was used to model these characteristics.

RESULTS

Women with TN tumors were younger, African American, Hispanic, and of lower socioeconomic status (SES), whereas women with DN tumors were slightly older; African American, and Asian/Pacific Islander. Women with TN and DN tumors presented with larger, higher grade, and higher stage than women with OBC. Survival among women with TN tumors was poorer compared with that among women with OBC but was nearly the same as that of women with DN tumors. Results of the regression analysis indicated that disease stage, tumor grade, SES, and race/ethnicity were significant risk factors for survival. Negative ER and PR status was associated with an increased risk of death. There was a small but significant difference in both long-term and short-term survival patients who had TN tumors compared with patients who had DN tumors.

CONCLUSIONS

Patients with TN tumors shared many clinical, demographic, and tumor features and had survival that was very similar survival to that of patients with DN tumors, and survival for both groups contrasted greatly with survival for patients with OBC. Disease stage, tumor grade, SES, race/ethnicity, negative ER and PR status, rather than negative HER2 status, were risk factors for survival.

Barriers to adequate follow-up during adjuvant therapy may be important factors in the worse outcome for Black women after breast cancer treatment

Introduction

Black women appear to have worse outcome after diagnosis and treatment of breast cancer. It is still unclear if this is because Black race is more often associated with known negative prognostic indicators or if it is an independent prognostic factor. To study this, we analyzed a patient cohort from an urban university medical center where these women made up the majority of the patient population.

Methods

We used retrospective analysis of a prospectively collected database of breast cancer patients seen from May 1999 to June 2006. Time to recurrence and survival were analyzed using the Kaplan-Meier method, with statistical analysis by chi-square, log rank testing, and the Cox regression model.

Results

265 female patients were diagnosed with breast cancer during the time period. Fifty patients (19%) had pure DCIS and 215 patients (81%) had invasive disease. Racial and ethnic composition of the entire cohort was as follows: Black (N = 150, 56.6%), Hispanic (N = 83, 31.3%), Caucasian (N = 26, 9.8%), Asian (N = 4, 1.5%), and Arabic (N = 2, 0.8%). For patients with invasive disease, independent predictors of poor disease-free survival included tumor size, node-positivity, incompletion of adjuvant therapy, and Black race. Tumor size, node-positivity, and Black race were independently associated with disease-specific overall survival.

Conclusion

Worse outcome among Black women appears to be independent of the usual predictors of survival. Further investigation is necessary to identify the cause of this survival disparity. Barriers to completion of standard post-operative treatment regimens may be especially important in this regard.

Racial disparity in stage at diagnosis and survival among adults with oral cancer in the US

OBJECTIVES

To explore distribution of stage at diagnosis and relative survival rates among US adults with oral cavity cancer in relation to race, and over time.

METHODS

We obtained 1973-2002 oral cancer incidence data from the Surveillance, Epidemiology, and End Results (SEER) Program, and computed proportions for each oral cavity site by stage at diagnosis, tumor size, and 5-year relative survival rates among Whites and Blacks.

RESULTS

A total of 46 855 cases of oral cavity cancer were reported to the SEER registry among adults > or =20 years between 1973 and 2002. African-Americans had a significantly higher proportion of cancer, mainly in the tongue, that had spread to a regional node or to a distant site at diagnosis than Whites: 67% versus 49% of tongue cancers reported from 1973 to 1987 (P < 0.001), and 70% versus 53% of those reported from 1988 to 2002 (P < 0.001). They had a significantly higher proportion of tongue cancer that were >4 cm in diameter at time of diagnosis (59% versus 44%; P < 0.001), and black men in particular experienced lower 5-year relative survival rates than white men, in particular, for tongue cancer (25% versus 43% from 1973 to 1987, and 31% versus 53% from 1988 to 2002).

CONCLUSION

There are significant racial disparities with respect to stage at diagnosis and survival among adults with oral cancer reported to the SEER registry from 1973 to 2002. One possible explanation for the lower survival among Blacks may be a difference in access to, and utilization of, healthcare services.

Descriptive analysis of estrogen receptor (ER)-negative, progesterone receptor (PR)-negative, and HER2-negative invasive breast cancer, the so-called triple-negative phenotype: a population-based study from the California cancer Registry

BACKGROUND

Tumor markers are becoming increasingly important in breast cancer research because of their impact on prognosis, treatment, and survival, and because of their relation to breast cancer subtypes. The triple-negative phenotype is important because of its relation to the basal-like subtype of breast cancer.

METHODS

Using the population-based California Cancer Registry data, we identified women diagnosed with triple-negative breast cancer between 1999 and 2003. We examined differences between triple-negative breast cancers compared with other breast cancers in relation to age, race/ethnicity, socioeconomic status (SES), stage at diagnosis, tumor grade, and relative survival.

RESULTS

A total of 6370 women were identified as having triple-negative breast cancer and were compared with the 44,704 women with other breast cancers. Women with triple-negative breast cancers were significantly more likely to be under age 40 (odds ratio [OR], 1.53), and non-Hispanic black (OR, 1.77) or Hispanic (OR, 1.23). Regardless of stage at diagnosis, women with triple-negative breast cancers had poorer survival than those with other breast cancers, and non-Hispanic black women with late-stage triple-negative cancer had the poorest survival, with a 5-year relative survival of only 14%.

CONCLUSIONS

Triple-negative breast cancers affect younger, non-Hispanic black and Hispanic women in areas of low SES. The tumors were diagnosed at later stage and were more aggressive, and these women had poorer survival regardless of stage. In addition, non-Hispanic black women with late-stage triple-negative breast cancer had the poorest survival of any comparable group.

The black:white disparity in breast cancer mortality: the example of Chicago

OBJECTIVE

The black:white disparity in breast cancer mortality has been increasing in the U.S. In order to gain insight into this disparity in Chicago, we examined mortality data together with other important measures associated with breast cancer.

METHODS

Trends in black:white female breast cancer mortality, incidence, stage at diagnosis, and mammography screening in Chicago were examined using data from the Illinois State Cancer Registry, Illinois Department of Public Health Vital Records, and the Illinois Behavioral Risk Factor Surveillance System.

RESULTS

The breast cancer mortality rate for black women in Chicago for 1999-2003 was 49% higher than that of white women, but the disparity is a recent phenomenon that is increasing rapidly. In 2003 the black rate was 68% higher than the white rate. Mortality rates were similar in the 1980's and only started to diverge in the 1990's as a result of a sharp improvement in mortality among white women contrasted with no improvement for black women. This lack of progress for black women is perplexing given that self-reported mammography screening rates have been the same for blacks and whites in Chicago since at least 1996 and that the early detection of breast cancer for black women has been increasing.

CONCLUSIONS

There has been no improvement in mortality from breast cancer for black women in Chicago in 23 years. This study, along with a review of the literature, lends support to the hypothesis that the disparities in breast cancer mortality are due to differential access to mammography, differential quality in mammography, and differential access to treatment for breast cancer. Fortunately, all three are amenable to intervention, which would help ameliorate this unacceptable disparity.

Are there racial differences in breast cancer treatments and clinical outcomes for women treated at M.D. Anderson Cancer Center?

PURPOSE

To determine the influence of race on breast cancer treatment and on recurrence and breast cancer specific death.

PATIENTS AND METHODS

The study population consisted of 6,054 African-American or white women who were diagnosed with breast cancer and received at least one of the treatments including mastectomy or breast conservative surgery, radiation, adjuvant chemotherapy, neo-adjuvant chemotherapy, and adjuvant endocrine therapy at M.D. Anderson Cancer Center between June 1997 and February 2005. The clinical outcomes were disease-free survival and breast-cancer-specific survival. Logistic regression analysis was performed to investigate if race was associated with the selection of each primary treatment while adjusting for tumor characteristics at diagnosis. Cox proportional hazards model was used to determine the effect of race on recurrence-free survival and breast-cancer-specific survival controlling for tumor characteristics, presence of co-morbidity conditions and use of these treatments.

RESULTS

The use of any primary treatment for breast cancer was not significantly different by race after adjusting for tumor characteristics and co-morbidity conditions. Although tumor characteristics at diagnosis explained the major differences in clinical outcomes, race remained an independent prognostic factor for breast-cancer-specific survival (P=0.002), and a marginally significant factor for disease-free survival (P=0.063) in multivariate analyses.

CONCLUSION

Equal treatment may not lead to equal clinical outcomes given similar tumor characteristics at diagnosis. To reduce racial differences in breast cancer recurrence and survival, it is important to have a better understanding of differences in tumor biology by race and to promote the use of early detection programs among African-American women.

Breast cancer in African-American women: differences in tumor biology from European-American women

Disparities exist between African-American and European-American women in the incidence and nature of breast cancer. African-American women are more often diagnosed with breast cancer at an earlier age and with more aggressive disease, characterized by higher grade and negative estrogen and progesterone receptor status. Recent findings reveal specific gene expression patterns associated with the more aggressive breast cancers observed in African-American women. An overview of the current literature about racial differences in breast cancer prompts questions for future research to elucidate causes for the apparent disparities in tumor biology.

Is risk of axillary lymph node metastasis associated with proximity of breast cancer to the skin?

INTRODUCTION

Risk of axillary lymph node metastasis, the most important predictor of disease-free and overall survival in breast cancer patients, is estimated primarily from histologic features of the primary cancer including tumor size, histologic type and grade, and hormone receptor expression. Based upon a clinical impression, and research showing that palpable cancers are more likely to be node positive, we hypothesized that primary breast cancers more proximal to the skin of the breast are more likely to be positive for axillary lymph node metastasis.

METHODS

This is a retrospective medical record review of 209 women with stage T1 or T2 (</=5.0 cm) invasive breast cancer who received dedicated breast ultrasound at a single mammography clinic in Columbia, South Carolina, between 1997 and 2002.

RESULTS

None of the 26 cancers more than 14 mm from the skin had metastasized to axillary lymph nodes. In logistic regression modeling only tumor size, histologic grade and tumor proximity to the skin (as a categorical variable) were significantly associated with odds of axillary metastasis. Among cancers within 14 mm of the skin, proximity was not an independent predictor.

CONCLUSIONS

Stage T1 and T2 breast cancers located less proximally to the skin may be less likely to spread to the axillary lymph nodes. We observed what appears to be a threshold at approximately 14 mm from the skin (based upon this group of patients): none of 26 cancers below this level had spread to axillary nodes. Further research is needed to confirm these provocative findings.

Meta-analysis of survival in African American and white American patients with breast cancer: ethnicity compared with socioeconomic status

PURPOSE

The extent to which socioeconomic disadvantages and inadequate health care access account for the disproportionately elevated mortality hazard observed in African American compared with white American patients with breast cancer is poorly defined.

METHODS

We identified 20 studies reported between January 1980 and June 2005 that provided survival analyses in patients with breast cancer after adjusting for ethnicity and some measurement of socioeconomic status. These studies also adjusted for age and stage of disease at time of diagnosis.

RESULTS

The pooled outcome data yielded estimates for the mortality hazard in 14,013 African American and 76,111 white American patients with breast cancer. Studies varied in their methods for assigning socioeconomic status, with most relying on area-wide measures such as census tract and census block data. The combined analysis (adjusted for age, stage, and socioeconomic status) revealed that African American ethnicity was associated with a statistically significant excess mortality risk in overall survival (mortality hazard, 1.27; 95% CI, 1.18 to 1.38) and in breast cancer-specific survival (mortality hazard, 1.19; 95% CI, 1.10 to 1.29).

CONCLUSION

Our pooled analysis demonstrated that African American ethnicity is a significant and independent predictor of poor outcome from breast cancer, even after accounting for socioeconomic status by conventional measures. These findings support the need for further investigation of the biologic, genetic, and sociocultural factors that may influence survival in African American patients with breast cancer.