African-American race is associated with a poorer overall survival rate for breast cancer patients treated with mastectomy and doxorubicin-based chemotherapy

Translational Epidemiology: Genetic Ancestry in Breast Cancer: What Is the Role of Genetic Ancestry and Socioeconomic Status in Triple-Negative Breast Cancer?

Racial/ethnic and socioeconomic disparities seen in triple-negative breast cancer (TNBC) have prompted questions regarding the role of genetic ancestry in breast cancer (BC) subtype development, tumor biology, and ultimately prognosis. The causes of disparities in TNBC are influenced greatly by both sociopolitical factors and genetic ancestry, and now, the potential genomic underpinnings of social factors. To comprehensively understand disparities in TNBC, it is critical to take a translational epidemiologic approach that takes into account genomic and non-genomic factors. Understanding the interplay between genetic ancestry and social genomics and their proportional influence on outcomes can guide our priorities for screening, diagnosis, and interventions for this aggressive BC subtype.

Clinical Outcomes and Immune Markers by Race in a Phase I/II Clinical Trial of Durvalumab Concomitant with Neoadjuvant Chemotherapy in Early-Stage TNBC

PURPOSE

The incidence of triple-negative breast cancer (TNBC) is higher among Black or African American (AA) women, yet they are underrepresented in clinical trials. To evaluate safety and efficacy of durvalumab concurrent with neoadjuvant chemotherapy for stage I-III TNBC by race, we enrolled additional AA patients to a Phase I/II clinical trial.

PATIENTS AND METHODS

Our study population included 67 patients. The primary efficacy endpoint was pathologic complete response (pCR; ypT0/is, N0) rate. χ2 tests were used to evaluate associations between race and baseline characteristics. Cox proportional hazards models were used to assess association between race and overall survival (OS) and event-free survival (EFS). Multivariate logistic regression analyses were used to evaluate associations between race and pCR, immune-related adverse events (irAE) and recurrence.

RESULTS

Twenty-one patients (31%) self-identified as AA. No significant associations between race and baseline tumor stage (P = 0.40), PD-L1 status (0.92), and stromal tumor-infiltrating lymphocyte (sTIL) count (P = 0.57) were observed. pCR rates were similar between AA (43%) and non-AA patients (48%; P = 0.71). Three-year EFS rates were 78.3% and 71.4% in non-AA and AA patients, respectively [HR, 1.451; 95% confidence interval (CI), 0.524-4.017; P = 0.474]; 3-year OS was 87% and 81%, respectively (HR, 1.72; 95% CI, 0.481-6.136; P = 0.405). The incidence of irAEs was similar between AA and non-AA patients and no significant associations were found between irAEs and pathologic response.

CONCLUSIONS

pCR rates, 3-year OS and EFS after neoadjuvant immunotherapy and chemotherapy were similar in AA and non-AA patients. Toxicities, including the frequency of irAEs, were also similar.

Tumor immune microenvironment of self-identified African American and non-African American triple negative breast cancer

Differences in the tumor immune microenvironment may result in differences in prognosis and response to treatment in cancer patients. We hypothesized that differences in the tumor immune microenvironment may exist between African American (AA) and NonAA patients, due to ancestry-related or socioeconomic factors, that may partially explain differences in clinical outcomes. We analyzed clinically matched triple-negative breast cancer (TNBC) tissues from self-identified AA and NonAA patients and found that stromal TILs, PD-L1 IHC-positivity, mRNA expression of immune-related pathways, and immunotherapy response predictive signatures were significantly higher in AA samples (p < 0.05; Fisher's Exact Test, Mann-Whitney Test, Permutation Test). Cancer biology and metabolism pathways, TAM-M2, and Immune Exclusion were significantly higher in NonAA samples (p < 0.05; Permutation Test, Mann-Whitney Test). There were no differences in somatic tumor mutation burden. Overall, there is greater immune infiltration and inflammation in AA TNBC and these differences may impact response to immune checkpoint inhibitors and other therapeutic agents that modulate the immune microenvironment.

Racial disparity in distant recurrence-free survival in patients with localized breast cancer: A pooled analysis of National Surgical Adjuvant Breast and Bowel Project trials

BACKGROUND

Black race is associated with worse outcome in patients with breast cancer. The distant relapse-free survival (DRFS) between Black and White women with localized breast cancer who participated in National Cancer Institute-sponsored clinical trial was evaluated.

METHODS

Pooled data were analyzed from 8 National Surgical Adjuvant Breast and Bowel Project (NSABP) trials including 9702 women with localized breast cancer treated with adjuvant chemotherapy (AC, n = 7485) or neoadjuvant chemotherapy (NAC, n = 2217), who self-reported as Black (n = 1070) or White (n = 8632) race. The association between race and DRFS was analyzed using log-rank tests and multivariate Cox regression.

RESULTS

After adjustment for covariates including age, tumor size, nodal status, body mass index and taxane use, and treatment (AC vs NAC), Black race was associated with an inferior DRFS in estrogen receptor-positive (ER+; hazard ratio [HR], 1.24; 95% CI, 1.05-1.46; P = .01), but not in ER- disease (HR, 0.97; 95% CI, 0.83-1.14; P = .73), and significant interaction between race and ER status was observed (P = .03). There was no racial disparity in DRFS among patients with pathologic complete response (pCR) (log-rank P = .8). For patients without pCR, Black race was associated with worse DRFS in ER+ (HR, 1.67; 95% CI, 1.14-2.45; P = .01), but not in ER- disease (HR, 0.91; 95% CI, 0.65-1.28; P = .59).

CONCLUSIONS

Black race was associated with significantly inferior DRFS in ER+ localized breast cancer treated with AC or NAC, but not in ER- disease. In the NAC group, racial disparity was also observed in patients with residual ER+ breast cancer at surgery, but not in those who had pCR.

LAY SUMMARY

Black women with breast cancer have worse outcomes compared with White women. We investigated if this held true in the context of clinical trials that provide controlled treatment setting. Black women with cancer expressing estrogen receptors (ERs) had worse outcome than White women. If breast cancers did not express ERs, there was no racial disparity in outcome. We also observed racial disparity in women who received chemotherapy before their cancer was removed, but only if they had cancer expressing ERs and residual disease on completion of treatment. If the cancer disappeared with presurgical chemotherapy, there was no racial disparity.

Racial Disparities in Triple Negative Breast Cancer: A Review of the Role of Biologic and Non-biologic Factors

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that lacks expression of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor (HER2). TNBC constitutes about 15–30 percent of all diagnosed invasive breast cancer cases in the United States. African-American (AA) women have high prevalence of TNBC with worse clinical outcomes than European-American (EA) women. The contributing factors underlying racial disparities have been divided into two major categories based on whether they are related to lifestyle (non-biologic) or unrelated to lifestyle (biologic). Our objective in the present review article was to understand the potential interactions by which these risk factors intersect to drive the initiation and development of the disparities resulting in the aggressive TNBC subtypes in AA women more likely than in EA women. To reach our goal, we conducted literature searches using MEDLINE/PubMed to identify relevant articles published from 2005 to 2019 addressing breast cancer disparities primarily among AA and EA women in the United States. We found that disparities in TNBC may be attributed to racial differences in biological factors, such as tumor heterogeneity, population genetics, somatic genomic mutations, and increased expression of genes in AA breast tumors which have direct link to breast cancer. In addition, a large number of non-biologic factors, including socioeconomic deprivation adversities associated with poverty, social stress, unsafe neighborhoods, lack of healthcare access and pattern of reproductive factors, can promote comorbid diseases such as obesity and diabetes which may adversely contribute to the aggression of TNBC biology in AA women. Further, the biological risk factors directly linked to TNBC in AA women may potentially interact with non-biologic factors to promote a higher prevalence of TNBC, more aggressive biology, and poor survival. The relative contributions of the biologic and non-biologic factors and their potential interactions is essential to our understanding of disproportionately high burden and poor survival rates of AA women with TNBC.

Understanding breast cancer disparities-a multi-scale challenge

Despite convergence of overall breast cancer incidence rates between European American (EA) and African American (AA) women, disparities in mortality persist. The factors contributing to differences in mortality rates across population groups remain controversial and range from population genetics to sociodemographic influences. This review explores the complex multi-factorial nature of tumor-intrinsic and -extrinsic factors that impact the biology and clinical outcomes of breast cancer patients. In addition to summarizing the current state of breast cancer disparities research, we also motivate the development of integrative multi-scale approaches involving interdisciplinary teams to tackle this complex clinical challenge.

Genomic analysis of racial differences in triple negative breast cancer

Triple negative breast cancer (TNBC) is more prevalent in African Americans (AAs), has a more aggressive clinical course including a higher mortality rate and an increased occurrence of metastases. This study was designed to determine if racial differences at the molecular level might explain the more aggressive phenotype in AAs. Mutation profiling, was performed on 51 AA and 77 CA tumor/ normal pairs. Transcript expression analysis was performed on 35AA and 37CA. Genes with high frequency mutation rates such as MUC4 and TP53 were common to both racial populations, however genes that were less frequently mutated differed between the races suggesting that those cause the more aggressive nature of TNBC in AA women. JAK-Stat and HER2 signaling were unique to the AA and PTEN and mTOR were unique to the CA profiles. Many pathways identified by the mutational profiles were predicted to be down-regulated by the transcript expression profiles.

Black race and distant recurrence after neoadjuvant or adjuvant chemotherapy in breast cancer

Black race compared to white race is associated with more advanced stage and biologically aggressive breast cancer. Consequently, black patients are more frequently treated with neoadjuvant chemotherapy (NAC) than white patients. However, it is unclear how distant recurrence-free survival (DRFS) of black patients treated with NAC, compares to DRFS of black patients treated with adjuvant chemotherapy (AC). We evaluated the association between race, distant recurrence, and type of chemotherapy (AC or NAC) in localized or locally advanced breast cancer. We evaluated DRFS in 807 patients, including 473 black, 252 white, 56 Hispanic, and 26 women of other or mixed race. The association between AC or NAC and DRFS was examined using multivariate Cox proportional hazard models that included race, age, stage, estrogen receptor (ER) and triple negative (TN) status. When the black and white subjects were pooled for the analysis the features associated with worse DRFS included stage III disease and age < 50 years, but not ER-negative disease, TN disease, the use of NAC, or black race. However, in the analysis stratified by race NAC was associated with worse DRFS compared to AC in black (HR 2.70; 95% CI 1.73-4.22; p < 0.0001), but not in white women (HR 1.29, 95% CI 0.56-2.95; p = 0.36). Black patients treated with NAC had worse DRFS than black patients treated with AC, or white patients treated with either NAC or AC. These findings need to be validated in a large-scale observational study and the effect of NAC on the breast cancer microenvironment in black women needs to be further evaluated.

Race is associated with completion of neoadjuvant chemotherapy for breast cancer

BACKGROUND

Completion of prescribed neoadjuvant chemotherapy for breast cancer is paramount to patients obtaining full benefit from the treatment; however, factors affecting neoadjuvant chemotherapy completion are not known. We hypothesized that race is a predictor of completion of neoadjuvant chemotherapy in patients with breast cancer.

METHODS

All patients with breast cancer treated with neoadjuvant chemotherapy 2009-2016 at a single institution were stratified by completion of neoadjuvant chemotherapy and by race. Univariate analysis and multivariable logistic regression were used to identify patient and tumor characteristics that affected the rate of neoadjuvant chemotherapy completion.

RESULTS

A total of 92 (74%) of 124 patients completed their prescribed neoadjuvant chemotherapy. On univariate analysis, white patients were more likely to complete neoadjuvant chemotherapy than non-white patients (76% vs 50%, P = .006). Non-white patients were more likely to have government insurance and larger prechemotherapy tumors (both, P < .05), but these factors were not associated with rates of neoadjuvant chemotherapy completion. After controlling for age, insurance status, tumor size, and estrogen receptor status, whites remained associated with completion of neoadjuvant chemotherapy (OR 3.65, P = .014).

CONCLUSION

At our institution, white patients with breast cancer were more likely than non-white patients to complete neoadjuvant chemotherapy. Further investigation into the underlying factors impacting this disparity is needed.

Literature review of data-based models for identification of factors associated with racial disparities in breast cancer mortality

In the United States, early detection methods have contributed to the reduction of overall breast cancer mortality but this pattern has not been observed uniformly across all racial groups. A vast body of research literature shows a set of health care, socio-economic, biological, physical, and behavioural factors influencing the mortality disparity. In this paper, we review the modelling frameworks, statistical tests, and databases used in understanding influential factors, and we discuss the factors documented in the modelling literature. Our findings suggest that disparities research relies on conventional modelling and statistical tools for quantitative analysis, and there exist opportunities to implement data-based modelling frameworks for (1) exploring mechanisms triggering disparities, (2) increasing the collection of behavioural data, and (3) monitoring factors associated with the mortality disparity across time.

Obesity and Triple-Negative Breast Cancer: Disparities, Controversies, and Biology

Once considered a problem of Western nations, obesity (body mass index ≥30 kg/m²) has rapidly increased since the 1970s to become a major threat to world health. Since 1970, the face of obesity has changed from a disease of affluence and abundance to a disease of poverty. During the last 10 years, studies have mechanistically linked obesity and an obese tumor microenvironment with signaling pathways that predict aggressive breast cancer biology. For example, in the United States, African American women are more likely than non-Hispanic European American women to be obese and to be diagnosed with triple-negative breast cancer (TNBC). In 2008, the Carolina Breast Study found that obesity (increased waist/hip ratio) was linked to an increased incidence of TNBC in premenopausal and postmenopausal African American women. Subsequently, several groups have investigated the potential link between obesity and TNBC in African American women. To date, the data are complex and sometimes contradictory. We review epidemiologic studies that investigated the potential association among obesity, metabolic syndrome, and TNBC in African American women and mechanistic studies that link insulin signaling to the obese breast microenvironment, tissue inflammation, and aggressive TNBC biology.

Obesity and Triple-Negative Breast Cancer: Disparities, Controversies, and Biology

Once considered a problem of Western nations, obesity (body mass index ≥30 kg/m²) has rapidly increased since the 1970s to become a major threat to world health. Since 1970, the face of obesity has changed from a disease of affluence and abundance to a disease of poverty. During the last 10 years, studies have mechanistically linked obesity and an obese tumor microenvironment with signaling pathways that predict aggressive breast cancer biology. For example, in the United States, African American women are more likely than non-Hispanic European American women to be obese and to be diagnosed with triple-negative breast cancer (TNBC). In 2008, the Carolina Breast Study found that obesity (increased waist/hip ratio) was linked to an increased incidence of TNBC in premenopausal and postmenopausal African American women. Subsequently, several groups have investigated the potential link between obesity and TNBC in African American women. To date, the data are complex and sometimes contradictory. We review epidemiologic studies that investigated the potential association among obesity, metabolic syndrome, and TNBC in African American women and mechanistic studies that link insulin signaling to the obese breast microenvironment, tissue inflammation, and aggressive TNBC biology.

Enrollment and Racial Disparities in Cancer Treatment Clinical Trials in North Carolina

BACKGROUND

Clinical trials provide access to innovative, high-quality cancer treatment. Simultaneously, broad access helps to ensure that trials include heterogeneous patient populations, which improves the generalizability of findings and the development of interventions that are effective for diverse populations. We provide updated data describing enrollment into cancer treatment trials in North Carolina.

METHODS

For the period 1996-2009, person-level data regarding cancer clinical trial enrollment and cancer incidence were obtained from the North Carolina Central Cancer Registry and the National Cancer Institute (NCI). Enrollment rates were estimated as the ratio of trial enrollment to cancer incidence for race, sex, and year for each county, Area Health Education Center region, and the state overall. Enrollment rates for common cancers are presented.

RESULTS

From 1996 to 2009, North Carolina NCI treatment trial enrollment rates were 2.4% and 2.2% for white patients and minority patients, respectively. From 2007 to 2009, rates were 3.8% for white women, 3.5% for minority women, 1.3% for white men, and 1.0% for minority men; there was greater enrollment among more urban populations (2.4%) than among the most rural populations (1.5%).

LIMITATIONS

This study is limited to NCI-sponsored treatment trials in North Carolina. Policies governing collection of original data necessitate a delay in data availability.

CONCLUSIONS

Effort is needed to ensure trial access and enrollment among all North Carolina populations. Specifically, we identified racial and sex disparities, particularly for certain cancers (eg, breast cancer). Programs in North Carolina and across the nation can use the methods we employed to assess their success in broadening clinical trial enrollment to include diverse populations.

Triple-negative breast cancer in African-American women: disparities versus biology

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype that disproportionately affects BRCA1 mutation carriers and young women of African origin. There is evidence that African-American women with TNBC have worse clinical outcomes than women of European descent. However, it is unclear whether survival differences persist after adjusting for disparities in access to health-care treatment, co-morbid disease and income. It remains controversial whether TNBC in African-American women is a molecularly distinct disease or whether African-American women have a higher incidence of aggressive biology driven by disparities: there is evidence in support of both. Understanding the relative contributions of biology and disparities is essential for improving the poor survival rate of African-American women with TNBC.

Adherence to intravenous chemotherapy in African American and white women with early-stage breast cancer

BACKGROUND

Adherence to intravenous chemotherapy offers survival and recurrence-free benefits for women diagnosed with early-stage breast cancer. However, previous studies have found that African American women are more likely to discontinue intravenous chemotherapy early, thus shortening their survival. Yet the existence of racial differences and predictors of adherence to chemotherapy treatment between African American and white women are largely understudied or inconsistent.

OBJECTIVE

The purposes of this study were to examine factors that influence the decision to adhere to chemotherapy in African American and white women diagnosed with early-stage breast cancer and to test for racial differences that may exist in this sample.

INTERVENTIONS/METHODS

The study recruited a convenience sample of 99 African American and white women. Factors examined were sociodemographic variables (age, race, access to healthcare), social support, religious coping, chemotherapy adverse effects, depression, breast cancer knowledge, health beliefs, cancer fatalism, and days from diagnosis to treatment. Data analyses included logistic regression modeling.

RESULTS

No racial differences in adherence to intravenous chemotherapy between African American and white women were found (χ = 2.627, P = .10). Days to treatment (odds ratio [OR], 0.982, P = .058), health insurance (OR, 0.121; P = .016), change in depression (OR, 0.935; P = .118), and symptom severity (OR, 0.950; P = .038) were independently associated with nonadherence to chemotherapy.

CONCLUSIONS

This study provides emerging evidence of factors that may be potentially modified with interventions at the clinical setting.

IMPLICATIONS FOR PRACTICE

The findings can be used to spearhead future intervention studies that improve treatment decision making to chemotherapy adherence.

Long-term survival of women with locally advanced breast cancer with ≥ 10 involved lymph nodes at diagnosis

BACKGROUND

Axillary lymph node status at diagnosis remains the strongest predictor of long-term survival in breast cancer. Patients with more than ten axillary lymph nodes at diagnosis have a poor long-term survival. In this single institutional study, we set out to evaluate the prognosis of this high-risk group in the era of multimodality therapy.

MATERIALS AND METHODS

In this retrospective study, we looked at all breast cancer patients with greater than ten axillary lymph nodes diagnosed at Mount Sinai Medical Center (MSMC) from January 1st 1990 to December 31st 2007 (n=161). In the univariate analysis, descriptive frequencies, median survival, and 5- and 10-year survival rates were estimated for common prognostic factors. A multivariate prognostic analysis for time-to-event data, using the extended Cox regression model was carried out.

RESULTS

With a median and mean follow-up of 70 and 89.9 months, respectively, the overall median survival was estimated to be 99 months. The five-year disease-free survival (DFS) was 59.3% and the ten-year DFS was 37.9%, whereas the five- and ten-year overall survival (OS) was 66.6% and 43.9%, respectively. Multivariate analysis revealed a significant improvement in DFS among black patients compared to whites (p=0.05), improved DFS and OS among young patients (ages 21-45) compared to elderly patients (age greater than 70) (p=0.00176, p=0.0034, respectively), and improved DFS and OS among patients whose tumors were ER positive (p=0.049, p=0.0034).

CONCLUSIONS

In this single institution study of patients with greater than 10 positive axillary nodes, black patients had a significantly improved DFS compared with white patients. Young age and ER tumor positivity was associated with improved outcomes. Using multivariate analysis, there were no other variables associated with statistically significant improvements in DFS or OS including date of diagnosis. Further work is needed to improve breast cancer survival in this subgroup of patients.

Improved clinical outcomes associated with vitamin D supplementation during adjuvant chemotherapy in patients with HER2+ nonmetastatic breast cancer

BACKGROUND

Vitamin D (VD) supplementation has pleiotropic effects that extend beyond their impact on bone health, including the disruption of downstream VD receptor signaling and human epidermal growth factor receptor 2 (HER2) signaling through the ErbB2/AKT/ERK pathway. In the present study, we examined our institutional experience with patients having nonmetastatic HER2-positive (HER(+)) breast cancer and hypothesized that those patients who received VD supplementation during neoadjuvant chemotherapy would have improved long-term outcomes.

PATIENTS AND METHODS

We performed a retrospective review of all patients (n = 308) given trastuzumab-based chemotherapy between 2006 and 2012 at the University of Miami/Sylvester Comprehensive Cancer Center (UM/SCCC). We identified 2 groups of patients for comparison-those who received VD supplementation during neoadjuvant chemotherapy (n = 134) and those who did not (n = 112). Univariate and multivariate Cox proportional hazard regression models were fitted to overall survival (OS) and disease-free survival (DFS).

RESULTS

More than half of the patients received VD during neoadjuvant chemotherapy (54.5%), with 60% receiving a dose < 10,000 units/wk and 33.3% having a VD deficiency at the start of therapy. In our final multivariate model, VD use was associated with improved DFS (hazard ratio [HR], 0.36; 95% confidence interval [CI], 0.15-0.88; P = .026], whereas larger tumor size was associated with worse DFS (HR, 3.52; 95% CI, 1.06-11.66; P = .04). There were no differences in OS based on any of the categories, including VD use, tumor size, number of metastatic lymph nodes, age at diagnosis, or lymphovascular invasion (LVI).

CONCLUSION

VD supplementation in patients with nonmetastatic HER2(+) breast cancer is associated with improved DFS.

Increasing Black:White disparities in breast cancer mortality in the 50 largest cities in the United States

INTRODUCTION

This paper presents race-specific breast cancer mortality rates and the corresponding rate ratios for the 50 largest U.S. cities for each of the 5-year intervals between 1990 and 2009.

METHODS

The 50 largest cities in the U.S. were the units of analysis. Numerator data were abstracted from national death files where the cause was malignant neoplasm of the breast (ICD-9=174 and ICD-10=C50) for women. Population-based denominators were obtained from the U.S. Census Bureau for 1990, 2000, and 2010. To measure the racial disparity, we calculated non-Hispanic Black:non-Hispanic White rate ratios (RRs) and confidence intervals for each 5-year period.

RESULTS

At the final time point (2005-2009), two RRs were less than 1, but neither significantly so, while 39 RRs were >1, 23 of them significantly so. Of the 41 cities included in the analysis, 35 saw an increase in the Black:White RR between 1990-1994 and 2005-2009. In many of the cities, the increase in the disparity occurred because White rates improved substantially over the 20-year study period, while Black rates did not. There were 1710 excess Black deaths annually due to this disparity in breast cancer mortality, for an average of about 5 each day.

CONCLUSION

This analysis revealed large and growing disparities in Black:White breast cancer mortality in the U.S. and many of its largest cities during the period 1990-2009. Much work remains to achieve equality in breast cancer mortality outcomes.

Outcome for patients with triple-negative breast cancer is not dependent on race/ethnicity

Introduction. Triple negative breast cancer (TNBC) is biologically aggressive and is associated with a worse prognosis. To understand the impact of race/ethnicity on outcome for patients with TNBC, confounding factors such as socioeconomic status (SES) need to be controlled. We examined the impact of race/ethnicity on a cohort of patients of low SES who have TNBC. Methods. 786 patients with Stage 0-III breast cancer were evaluated. Of these, 202 patients had TNBC (26%). Primary endpoints were cancer recurrence and death. ZIP code-based income tract and institutional financial data were used to assess SES. Data were analyzed using Kaplan-Meier survival analysis, log-rank tests, Cox Proportional hazard regression, chi square test, and t-tests. A P value ≤0.05 was considered statistically significant. Results. Of the 468 African-Americans (60%) in the database, 138 had TNBC; 64 of 318 Caucasians had TNBC. 80% of patients had an annual income of ≤$20,000. The 5-year overall survival was 77% for African-American women versus 72% for Caucasian women (P = 0.95). On multivariate analysis, race/ethnicity had an impact on disease-free survival (P = 0.027) but not on overall survival (P = 0.98). Conclusion. In a predominantly indigent population, race/ethnicity had no impact on overall survival for patients with triple negative breast cancer.

Primary tumor size, not race, determines outcomes in women with hormone-responsive breast cancer

INTRODUCTION

We sought to determine if there was a difference in outcomes in African-American compared with Caucasian women with hormone-responsive breast cancer, and whether this was related to race or other tumor and treatment variables.

METHODS

We included 1,205 patients with hormone-responsive breast cancer were identified in the Kentucky Cancer Registry (1996-2007). The effect of race on survival was evaluated using Kaplan-Meier and Cox regression methodologies.

RESULTS

In this cohort, 76.9% were Caucasian and 21.7% were African American. Compared with Caucasians, African-American women were older (57 vs 55 years; P = .032) and more likely to have larger tumors (19 vs 17 mm; P = .009). No significant racial differences in grade, operative, or systemic treatment were noted. Univariate analysis found no significant differences in disease-specific overall survival (DSS) or disease-free survival (DFS) between Caucasians and African Americans (5-year actuarial DSS, 93.6% vs 90.7%, respectively; P = .205; 5-year actuarial DFS, 91.5% vs 90.4%, respectively; P = .829). On multivariate analysis, only tumor size remained an independent predictor of DSS (odds ratio [OR], 1.021; 95% confidence interval [CI], 1.013-1.028; P < .001). Controlling for age, tumor size, and insurance status, race did not influence DSS or DFS (P = .913 and P = .857).

CONCLUSION

African Americans present with larger tumors than Caucasians; treatment is similar. Tumor size, not race, affects disease-specific outcomes in patients with breast cancer.

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.

Effect of metformin on survival outcomes in diabetic patients with triple receptor-negative breast cancer

BACKGROUND

Recent observational studies have shown that metformin use in diabetic patients decreases both cancer incidence and mortality. Metformin use is also independently predictive of pathologic complete response. In the current study, the authors explored the association between metformin use and survival outcomes in patients with triple receptor-negative breast cancer (TNBC) who were receiving adjuvant chemotherapy.

METHODS

The Breast Cancer Management System database of The University of Texas MD Anderson Cancer Center identified 1448 women who received adjuvant chemotherapy for TNBC between 1995 and 2007. Patients were categorized by diabetes status and metformin use. The Kaplan-Meier product-limit method was used to calculate distant metastasis-free survival (DMFS), recurrence-free survival (RFS), and overall survival (OS). Cox proportional hazards models were fit to determine the association between metformin use and survival outcomes.

RESULTS

The study cohort was comprised of 63 diabetic patients receiving treatment with metformin, 67 diabetic patients not receiving metformin, and 1318 nondiabetic patients. Patients in the diabetic groups tended to be older (P = .005); more diabetic patients were postmenopausal (P = .0007), black (P = .0001), and obese (P < .0001). At a median follow-up of 62 months, there were no significant differences with regard to 5-year DMFS (P = .23), RFS (P = .38), and OS (P = .58) between the 3 groups. Compared with the metformin group, patients who did not receive metformin (hazard ratio [HR], 1.63; 95% confidence interval [95% CI], 0.87-3.06 [P = .13]) and nondiabetic patients (HR, 1.62; 95% CI, 0.97-2.71 [P = .06]) tended to have a higher risk of distant metastases.

CONCLUSIONS

The findings of the current study suggest that metformin use during adjuvant chemotherapy does not significantly impact survival outcomes in diabetic patients with TNBC.

Racial differences in acute toxicities of neoadjuvant or adjuvant chemotherapy in patients with early-stage breast cancer

BACKGROUND

Racial disparities in breast cancer outcomes are attributed to differences in baseline tumour characteristics and biology, stage, age, ethnic background and socioeconomic factors. However, little is known about racial differences in treatment-related toxicities. We hypothesised that racial/ethnic differences result in differential tolerance to chemotherapy potentially, leading to compromised dose intensity/density of chemotherapy in patients with early-stage breast cancer.

METHODS

Data were collected from patients treated at five international centers for early breast cancer with the same adjuvant/neoadjuvant chemotherapy (FEC 100: fluorouracil 500mg/m(2), epirubicin 100mg/m(2), and cyclophosphamide 500mg/m(2),every 21d for 3-6 cycles). Toxicities were assessed by first episode of ⩾grade 2 toxicity.

RESULTS

Toxicities were compared according to four race/ethnicity groups (103 Caucasian, 30 African American, 164 Asian, and 34 Hispanic patients). Tumour characteristics across four race/ethnicity groups were similar. Asians had a significantly higher rate of grade 3 haematologic toxicity than Caucasians, African Americans or Hispanic women (32%, 16%, 10%, and 15%, respectively; p<0.05). In multivariate analysis, only lower BMI was associated with a higher incidence of ⩾grade 3 toxicities. However, no significant differences in chemotherapy dose intensity/density were shown across the four race/ethnicity groups.

CONCLUSION

Racial differences in acute toxicity were noted in women with breast cancer who were treated with FEC 100 chemotherapy, suggesting that extrapolating toxicities from chemotherapy across ethnicities is not possible and emphasising the need to validate safety of chemotherapeutic regimens in patients of different ethnicities by enhancing the participation of minorities in clinical trials.

Interactions among genes, tumor biology and the environment in cancer health disparities: examining the evidence on a national and global scale

Cancer incidence and mortality rates show great variations across nations and between population groups. These variations are largely explained by differences in age distribution, diet and lifestyle, access to health care, cultural barriers and exposure to carcinogens and pathogens. Cancers caused by infections are significantly more common in developing than developed countries, and they overproportionally affect immigrant populations in the USA and other countries. The global pattern of cancer is not stagnant. Instead, it is dynamic because of fluctuations in the age distribution of populations, improvements in cancer prevention and early detection in affluent countries and rapid changes in diet and lifestyle in parts of the world. For example, increased smoking rates have caused tobacco-induced cancers to rise in various Asian countries, whereas reduced smoking rates have caused these cancers to plateau or even begin to decline in Western Europe and North America. Some population groups experience a disproportionally high cancer burden. In the USA and the Caribbean, cancer incidence and mortality rates are excessively high in populations of African ancestry when compared with other population groups. The causes of this disparity are multifaceted and may include tumor biological and genetic factors and their interaction with the environment. In this review, we will discuss the magnitude and causes of global cancer health disparities and will, with a focus on African-Americans and selected cancer sites, evaluate the evidence that genetic and tumor biological factors contribute to existing cancer incidence and outcome differences among population groups in the USA.

Outcomes in black patients with early breast cancer treated with breast conservation therapy

BACKGROUND

The race-specific impact of prognostic variables for early breast cancer is unknown for black patients undergoing breast conservation.

METHODS AND MATERIALS

This was a retrospective study of 1,231 consecutive patients ≥40 years of age with Stage I-II invasive breast cancer treated with lumpectomy and radiation therapy at the University of Chicago Hospitals and affiliates between 1986 and 2004. Patients were classified as either black or nonblack. Cox proportional hazards regression was used to model the effects of known prognostic factors and interactions with race.

RESULTS

Median follow-up for surviving patients was 82 months. Thirty-four percent of patients were black, and 66% were nonblack (Caucasian, Hispanic, and Asian). Black patients had a poorer 10-year overall survival (64.6% vs. 80.8%; adjusted hazard ratio [HR], 1.59; 95% confidence interval [CI], 1.23-2.06) and 10-year disease-free survival (58.1% vs. 75.4%; HR 1.49; 95% CI, 1.18-1.89) compared with nonblack patients. Tumor sizes were similar between nonblack and black patients with mammographically detected tumors (1.29 cm vs. 1.20 cm, p = 0.20, respectively). Tumor size was significantly associated with overall survival (HR 1.48; 95% CI, 1.12-1.96) in black patients with mammographically detected tumors but not in nonblack patients (HR 1.09; 95% CI, 0.78-1.53), suggesting that survival in black patients depends more strongly on tumor size in this subgroup. Tests for race-size method of detection interactions were statistically significant for overall survival (p = 0.049), locoregional control (p = 0.036), and distant control (p = 0.032) and borderline significant for disease-free survival (p = 0.067).

CONCLUSION

Despite detection at comparable sizes, the prognostic effect of tumor size in patients with mammographically detected tumors is greater for black than in nonblack patients.

Pathologic complete response in breast cancer patients receiving anthracycline- and taxane-based neoadjuvant chemotherapy: evaluating the effect of race/ethnicity

BACKGROUND

The current study was conducted to evaluate the influence of race/ethnicity and tumor subtype in pathologic complete response (pCR) following treatment with neoadjuvant chemotherapy.

METHODS

A total of 2074 patients diagnosed with breast cancer between 1994 and 2008 who were treated with neoadjuvant anthracycline- and taxane-based chemotherapy were included. pCR was defined as no residual invasive cancer in the breast and axilla. The Kaplan-Meier product-limit was used to calculate survival outcomes. Cox proportional hazards models were fitted to determine the relationship of patient and tumor variables with outcome.

RESULTS

The median patient age was 50 years; 14.6% of patients were black, were 15.2% Hispanic, 64.3% were white, and 5.9% were of other race. There were no differences in pCR rates among race/ethnicity (12.3% in black, 14.2% in Hispanics, 12.3% in whites, and 11.5% in others, P = .788). Lack of pCR, breast cancer subtype, grade 3 tumors, and lymphovascular invasion were associated with worse recurrence-free survival (RFS) and overall survival (OS) (P </= .0001). Differences in RFS by race/ethnicity were noted in the patients with hormone receptor-positive disease (P = .007). On multivariate analysis, Hispanics had improved RFS (hazard ratio [HR], 0.69; 95% confidence interval [95% CI], 0.49-0.97) and OS (HR, 0.63; 95% CI, 0.41-0.97); blacks had a trend toward worse outcomes (RFS: HR, 1.28 [95% CI, 0.97-1.68] and OS: HR, 1.32 [95% CI, 0.97-1.81]) when compared with whites.

CONCLUSIONS

In this cohort of patients, race/ethnicity was not found to be significantly associated with pCR rates. On a multivariate analysis, improved outcomes were observed in Hispanics and a trend toward worse outcomes in black patients, when compared with white patients. Further research was needed to explore the potential differences in biology and outcomes.

Impact of race and ethnicity on outcomes for estrogen receptor-negative breast cancers: experience of an academic center with a charity hospital

BACKGROUND

African American women have a higher breast cancer mortality rate than Caucasian women. Estrogen receptor (ER)-negative tumors, which are more aggressive than ER-positive tumors, occur more frequently in African American women than in Caucasian women and may contribute to apparent disparities in outcomes. However, outcome results need to be controlled for socioeconomic status (SES). We evaluated the effect of race and ethnicity on outcomes of patients with ER-negative tumors by determining outcomes in African American and Caucasian women with low SES but similar access to care.

STUDY DESIGN

From a prospective database of 786 patients with stage 0 to III breast cancer, all 375 patients with ER-negative tumors were evaluated. Patients received standard definitive operations and adjuvant treatment. Compliance with treatment was more than 90%. Primary endpoints were cancer recurrence and overall survival (OS). Statistical analysis performed included Kaplan-Meier survival analysis, log-rank test, Cox proportional hazard model, Student's t-test, and chi-squared test. A p value < or = 0.05 was considered statistically significant.

RESULTS

Fifty-four percent of African American patients had ER-negative tumors versus 39% in Caucasian patients. In both groups, 69% of patients received free care or Medicaid, with a median income of $16,577 (range $15,367 to $36,788). Comparing the 2 racial and ethnic groups, mean tumor size (p = 0.19), tumor grade distribution (p = 0.32), nodal distribution (p = 0.50), stage distribution (p = 0.30), rate of mastectomy (p = 0.47), receipt of adjuvant chemotherapy (p = 0.07), and financial class distribution (p = 0.67) were not significantly different. The 5-year OS was 77% for both groups (p = 0.59). On multivariate analysis, race and ethnicity were not independent predictors of OS (p = 0.73).

CONCLUSIONS

In a predominantly indigent population, race and ethnicity had no impact on outcomes for ER-negative breast cancer.

Race/Ethnicity has no effect on outcome for breast cancer patients treated at an academic center with a public hospital

BACKGROUND

African American women have a higher breast cancer mortality rate than Caucasian women. To understand this difference, socioeconomic status (SES) needs to be controlled, which can be achieved by evaluating outcome within a population that is underinsured or low SES. We elected to examine the effect of race/ethnicity on outcome of patients with operable breast cancer by evaluating outcome in a population with low SES and similar access to care.

METHODS

From a prospective breast cancer database created in 1998, we examined outcome for 786 patients with stage 0 to III breast cancer treated up to September 2008. Patients were treated at Louisiana State University Health Sciences Center in Shreveport and E.A. Conway Hospital and the majority received standard definitive surgery as well as appropriate adjuvant treatment. Primary endpoints were cancer recurrence and death. Statistical analysis performed included Kaplan-Meier survival analysis, log-rank test, Cox proportional hazards model, independent-samples t test, and chi(2) test. P <or= 0.05 was considered statistically significant.

RESULTS

Sixty percent of patients were African American and over two thirds of patients were classified as either free care or Medicaid. The 5-year overall survival (OS) for African American and Caucasian patients was similar (81% and 84%, respectively; P = 0.23). On multivariate analysis, race/ethnicity was not an independent predictor of OS (P = 0.5); OS for the entire cohort was comparable with what was reported in the National Cancer Data Base.

CONCLUSION

In a predominantly indigent population, race/ethnicity had no effect on breast cancer outcome.

Racial disparities in cancer survival among randomized clinical trials patients of the Southwest Oncology Group

BACKGROUND

Racial disparities in cancer outcomes have been observed in several malignancies. However, it is unclear if survival differences persist after adjusting for clinical, demographic, and treatment variables. Our objective was to determine whether racial disparities in survival exist among patients enrolled in consecutive trials conducted by the Southwest Oncology Group (SWOG).

METHODS

We identified 19 457 adult cancer patients (6676 with breast, 2699 with lung, 1244 with colon, 1429 with ovarian, and 1843 with prostate cancers; 1291 with lymphoma; 2067 with leukemia; and 2208 with multiple myeloma) who were treated on 35 SWOG randomized phase III clinical trials from October 1, 1974, through November 29, 2001. Patients were grouped according to studies of diseases with similar histology and stage. Cox regression was used to evaluate the association between race and overall survival within each disease site grouping, controlling for available prognostic factors plus education and income, which are surrogates for socioeconomic status. Median and ten-year overall survival estimates were derived by the Kaplan-Meier method. All statistical tests were two-sided.

RESULTS

Of 19 457 patients registered, 2308 (11.9%, range = 3.9%-21.6%) were African American. After adjustment for prognostic factors, African American race was associated with increased mortality in patients with early-stage premenopausal breast cancer (hazard ratio [HR] for death = 1.41, 95% confidence interval [CI] = 1.10 to 1.82; P = .007), early-stage postmenopausal breast cancer (HR for death = 1.49, 95% CI = 1.28 to 1.73; P < .001), advanced-stage ovarian cancer (HR for death = 1.61, 95% CI = 1.18 to 2.18; P = .002), and advanced-stage prostate cancer (HR for death = 1.21, 95% CI = 1.08 to 1.37; P = .001). No statistically significant association between race and survival for lung cancer, colon cancer, lymphoma, leukemia, or myeloma was observed. Additional adjustments for socioeconomic status did not substantially change these observations. Ten-year (and median) overall survival rates for African American vs all other patients were 68% (not reached) vs 77% (not reached), respectively, for early-stage, premenopausal breast cancer; 52% (10.2 years) vs 62% (13.5 years) for early-stage, postmenopausal breast cancer; 13% (1.3 years) vs 17% (2.3 years) for advanced ovarian cancer; and 6% (2.2 years) vs 9% (2.7 years) for advanced prostate cancer.

CONCLUSIONS

African American patients with sex-specific cancers had worse survival than white patients, despite enrollment on phase III SWOG trials with uniform stage, treatment, and follow-up.

Reporting of race and ethnicity in breast cancer research: room for improvement

Health disparities in breast cancer outcomes according to race/ethnicity are well documented. Randomized clinical trials (RCT) offer an opportunity to evaluate differences in disease biology and response to therapy that may contribute to disparities. We conducted a PubMed search to identify all English language original reports of breast cancer RCT from October 2001 to October 2006. The primary outcomes of interest were reporting of accrual and results by race or ethnicity of trial subjects. We evaluated the correlation between study characteristics and reporting of race/ethnicity. A total of 197 eligible trials were identified among 29 journals. Accrual was reported by race in 17% of studies and results analyzed by race in only 2%. Reporting of race was associated with National Cancer Institute funding (38 vs. 13%, P = 0.001), US cooperative group trials (52 vs. 13%, P < 0.0001), trials with US sites (43 vs. 5%, P < 0.0001), and trials enrolling > 500 subjects (24 vs. 12%, P = 0.055). Pharmaceutical industry funding, # of centers, stage of disease, nature of experimental intervention and study outcomes were not associated with reporting of race. Among US studies reporting trial accrual by race/ethnicity, the mean accrual distribution was 81% white, 7.6% black, 9.6% Asian, and 7.2% Hispanic subjects. The majority of breast cancer RCT fail to report the race/ethnicity of participants. Low accrual of black subjects and failure to report accrual and outcomes by race in RCT may contribute to difficulty in understanding and overcoming health disparities in breast cancer.

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.

Treatment quality and outcomes of African American versus white breast cancer patients: retrospective analysis of Southwest Oncology studies S8814/S8897

PURPOSE

Women of African ancestry (AA) have lower WBC counts and are more likely to have treatment delays and discontinue adjuvant breast cancer therapy early compared with white women. We assessed the association between race and treatment discontinuation/delay, WBC counts, and survival in women enrolled onto breast cancer clinical trials.

PATIENTS AND METHODS

AA and white women from Southwest Oncology Group adjuvant breast cancer trials (S8814/S8897) were matched by age and protocol. Only the treatment arms in which patients were scheduled to receive six cycles of chemotherapy were analyzed.

RESULTS

A total of 317 pairs of patients (n = 634) were analyzed. At baseline, AA women had higher body-surface area (P < .0001) and lower WBC (P = .0009). AA women were more likely to have tumors that were > or = 2 cm (P = .01) and hormone receptor negative (P < .0001). AA women, versus white women, were marginally more likely to discontinue treatment early (11% v 7%, respectively; P = .07) or have one or more treatment delays (85% v 79%, respectively; P = .07) and were significantly more likely to experience the combined end point (discontinuation/delay; 87% v 81%, respectively; P = .04). The mean relative dose-intensity (RDI) was similar for both groups (87% in AA women v 86% in white women); however, overall, 43% had an RDI of less than 85%. After adjusting for baseline WBC and prognostic factors in a multivariate model, AA women had worse disease-free survival (hazard ratio [HR] = 1.56; 95% CI, 1.15 to 2.11; P = .005) and overall survival (HR = 1.95; 95% CI, 1.36 to 2.78; P = .0002). The inclusion of RDI and treatment delivery/quality in the regression had little impact on the results.

CONCLUSION

On cooperative group breast cancer trials, AA and white women had similar RDIs, but AA women were more likely to experience early discontinuation or treatment delay. Despite correcting for these factors and known predictors of outcome, AA women still had worse survival.

Triple receptor-negative breast cancer: the effect of race on response to primary systemic treatment and survival outcomes

PURPOSE

The goal of this study was to describe the effect of race on pathologic complete response (pCR) rates and survival outcomes in women with triple receptor-negative (TN) breast cancers.

PATIENTS AND METHODS

Four hundred seventy-one patients with TN breast cancer diagnosed between 1996 and 2005 and treated with primary systemic chemotherapy were included. pCR was defined as no residual invasive cancer in the breast and axillary lymph nodes. Overall survival (OS) and recurrence-free survival (RFS) were estimated using the Kaplan-Meier product-limit method and compared between groups using the log-rank test. Cox proportional hazards models were fitted for each survival outcome to determine the relationship of patient and tumor variables with outcome.

RESULTS

Median follow-up time was 24.5 months. One hundred patients (21.2%) were black, and 371 patients (78.8%) were white/other race. Seventeen percent of black patients (n = 17) and 25.1% of white/other patients (n = 93) achieved a pCR (P = .091). Three-year RFS rates were 68% (95% CI, 56% to 76%) and 62% (95% CI, 57% to 67%) for black and white/other patients, respectively, with no significant difference observed between the two groups (P = .302). Three-year OS was similar for the two racial groups. After controlling for patient and tumor characteristics, race was not significantly associated with RFS (hazard ratio [HR] = 1.08; 95% CI, 0.69 to 1.68; P = .747) or OS (HR = 1.08; 95% CI, 0.69 to 1.68; P = .735) when white/other patients were compared with black patients.

CONCLUSION

Race does not significantly affect pCR rates or survival outcomes in women with TN breast cancer treated in a single institution under the same treatment conditions.

Survival difference between non-Hispanic black and non-Hispanic white women with localized breast cancer: the impact of guideline-concordant therapy

OBJECTIVES

This study examined the impact of guideline-concordant therapy on the survival difference between non-Hispanic black (NHB) and non-Hispanic white (NHW) women with localized breast cancer.

METHODS

Data analyzed were from the CDC's NPCR Patterns of Care study in which seven population-based state cancer registries participated. We randomly selected 2,362 women who were diagnosed with a first primary localized breast cancer in 1997. Data were abstracted from hospital records, supplemented by information from physician offices and by linkages with state vital records and the National Death Index database.

RESULTS

NHB women were more likely than NHW women to receive breast conserving surgery without radiation therapy. In addition, the percentage of NHB women with hormone receptor-positive tumors who received hormonal therapy was lower than that of NHW women. Among those with a tumor size > 3 cm, NHB women were more likely than NHW women to receive multiagent chemotherapy. After controlling for age, the risk of dying from all causes of death was 2.35 times as high for NHB women compared to NHW women. Controlling for treatment further reduced black-white difference in survival with adjustment for sociodemographic and clinical variables.

CONCLUSION

NHB women were less likely than NHW women to receive guideline-concordant radiation therapy after breast conserving therapy and hormonal therapy but were more likely to receive chemotherapy. Racial differences in treatment contribute significantly to the worse survival of NHB women compared with NHW women.

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.

Association of surgery with improved survival in stage IV breast cancer patients

OBJECTIVE

This study aims to examine the role of surgery in patients with stage IV breast cancer.

BACKGROUND

Historically, women who present with metastatic breast cancer are not offered surgical treatment. However, recent reports indicate that surgery may improve outcome. Using a large database of women whom presented with stage IV breast cancer, we compared outcome of patients who had resection of their primary cancer to those who did not.

METHODS

Of 16,401 patients, 807 had stage IV disease at presentation, and 395 survived >90 days and were included in this analysis. Clinical and tumor characteristics, surgical treatment, and survival were compared for the surgically versus nonsurgically treated patients.

RESULTS

Two hundred and forty-two patients (61.3%) had definitive surgery for their primary tumor and 153 (38.7%) did not. Patients who underwent surgery were significantly older, were more likely to be white, more often had hormone receptor positive disease, had small primary tumors, and had fewer metastatic sites and less visceral involvement. The median survival of surgically treated patients was 27.1 months versus 16.8 months for patients without surgical resection (P < 0.0001). In multivariate analysis, which included surgical treatment, age, race, estrogen and progesterone receptor status, number of metastatic sites, and presence of visceral metastases, surgery remained an independent factor associated with improved survival (P = 0.006).

CONCLUSION

Patients with stage IV breast cancer who had definitive surgical treatment of their primary tumors had more favorable disease characteristics. However, after adjustment for these characteristics, surgical treatment remained an independent factor associated with improved survival.

Triple negative breast carcinoma and the basal phenotype: from expression profiling to clinical practice

Triple negative breast carcinomas (TNBCs) are a group of primary breast tumors with aggressive clinical behavior. Most TNBCs possess a basal phenotype (BP) and show varying degrees of basal cytokeratin and myoepithelial marker expression. The importance of recognizing these tumors came to light largely as the result of gene expression profiling studies that categorized breast cancer into 3 major groups. Two of these groups are defined by their respective expression of estrogen receptor and HER2. TNBCs represent a third group and are defined by negativity for hormone receptors and HER2. TNBCs currently lack effective targeted therapies and are frequently resistant to standard chemotherapeutic regimens. These tumors tend to occur in premenopausal women and members of specific ethnic groups and a subset are associated with heritable BRCA1 mutations. For patients with sporadic TNBCs and BP tumors, BRCA1 dysfunction seems to play a major role in the development and progression of disease. The pathologist's role in the diagnosis and characterization of TNBCs and BP tumors is currently being defined as we are acquiring knowledge of the biologic and genetic underpinnings that drive this heterogeneous group of diseases. This review will provide a historical prospective on TNBCs and tumors that express basal cytokeratins and myoepithelial makers. Additionally, we will discuss the molecular biologic, genetic and pathologic aspects of these tumors. Guidelines will be provided on how to best approach the diagnosis of these cases and on what input pathologists should provide clinicians to help develop optimal therapeutic and preventative strategies against this aggressive group of breast cancers.

Disparities in time to definitive surgical treatment between black and white women diagnosed with ductal carcinoma in situ

BACKGROUND

Although black women develop invasive breast cancer at a lower incidence than white women, the cancers they develop tend to be of a higher grade and are more likely estrogen receptor negative. There is very little information with regard to black women and ductal carcinoma in situ (DCIS). In addition, although various reasons have been proposed for the delay to screening for black women, a delay after diagnosis has also been recognized.

PURPOSE

The purpose of this study was to investigate disparities in time to treatment between black women and white women once DCIS has been diagnosed.

METHODS

A retrospective analysis of 37 black women and 37 matched white women treated for DCIS was performed. Matches were made based on the date of birth, date of diagnosis, date and type of surgery, and age at diagnosis. The time from the date of diagnosis to the date of surgery was ascertained.

RESULTS

Black women were 64% more likely to undergo a delay to surgery (>50 days) compared with white women (21% versus 13%, P < .05).

CONCLUSION

Black women are more likely not to reach surgery within 50 days of diagnosis, which is concerning, and further studies to investigate the cause of these delays are warranted.

Relationship between epidemiologic risk factors and breast cancer recurrence

PURPOSE

Early-stage breast cancers are biologically heterogeneous and vary in clinical behavior, supporting the role of factors other than tumor size and lymph node involvement as outcome determinants. We evaluated the effect of epidemiologic breast cancer risk factors on recurrence in women with early-stage disease.

PATIENTS AND METHODS

Medical records from 2,327 women with early-stage breast cancer, treated at the M.D. Anderson Cancer Center between 1985 and 2000, were used to derive information on epidemiologic, clinical, and histological factors. Cox proportional hazards models were used to estimate the hazard ratios of 5-year risk of breast cancer recurrence adjusted for treatment and stage. Statistical tests were two-sided.

RESULTS

None of the breast cancer risk factors were associated with recurrence, adjusting for tumor characteristics and treatment. A significant interaction between hormone replacement therapy (HRT) use and tumor hormone receptor status on risk of recurrence (P = .0003) was observed. Among ever-users of HRT, recurrence risk was two-fold lower for estrogen receptor (ER)--positive and progesterone receptor (PR)--positive tumors compared with ER- and PR-negative tumors; whereas, among never-users of HRT, there was no statistically significant association between recurrence risk and receptor status.

CONCLUSION

HRT users who develop receptor-positive early-stage disease have better outcomes than those who develop receptor-negative disease. Among never-users of HRT, the expected beneficial effect of ER- or PR-positive tumors on recurrence risk was absent. These data lend support to the notion that the biology of hormone receptor-positive disease in HRT users differs from that in nonusers.