Breast cancer stage at diagnosis: Caucasians versus Afro-Americans

Enhanced down-regulation of ALCAM/CD166 in African-American Breast Cancer

Background

Variation in tumor biology in African-American (AA) and Caucasian (CAU) women with breast cancer is poorly defined. Activated leukocyte cell adhesion molecule (ALCAM) is a bad prognostic factor of breast cancer yet it has never being studied in the AA population. We tested the hypothesis that ALCAM expression would be markedly lower in cases of AA breast cancer when compared to CAU.

Methods

Cases of breast cancer among AA (n = 78) and CAU (n = 95) women were studied. Immunohistochemical staining was used to semi-quantitatively score ALCAM expression in tumor and adjacent non-tumor breast tissues. Clinico-pathological characteristics including histological type, histological grade, tumor size, lymph node metastasis, estrogen receptor (ER), progesterone receptor (PR), and HER2-neu status were abstracted, and their association with ALCAM expression tested.

Results

Univariate analysis revealed that the level of ALCAM expression at intercellular junctions of primary tumors correlates with histological grade (AA; p = 0.04, CUA; p = 0.02), ER status (AA; p = 0.0004, CAU; p = 0.0015), PR status (AA; p = 0.002, CUA p = 0.034) and triple-negative tumor status (AA; p = 0.0002, CAU; p = 0.0006,) in both ethnic groups. Multivariate analysis demonstrated that ethnicity contribute significantly to ALCAM expression after accounting for basal-like subtype, age, histological grade, tumor size, and lymph node status. Compared to CAU tumors, the AA are 4 times more likely to have low ALCAM expression (p = 0.003).

Conclusions

Markedly low expression of ALCAM at sites of cell-cell contact in primary breast cancer tumors regardless of differentiation, size and lymph node involvement may contribute to the more aggressive phenotype of breast cancer among AA women.

Body size across the life course and risk of premenopausal and postmenopausal breast cancer in Black women, the Carolina Breast Cancer Study, 1993-2001

BACKGROUND

It is believed that greater adiposity is associated with reduced risk of breast cancer in premenopausal but increased risk in postmenopausal women. However, few studies have evaluated these relationships among Black women or examined anthropometric measures other than near-diagnosis body mass index (BMI).

PURPOSE

This study investigated associations between measures of body size across the life course and breast cancer risk among Black and White women living in the US South.

METHODS

We used data from the Carolina Breast Cancer Study, a population-based case-control study of invasive breast cancer in North Carolina women aged 20-74 years. We assessed nine body size variables, including age 10 relative weight; age 18 BMI; adult weight gain; "reference" BMI 1 year before interview; and post-diagnosis measured BMI and abdominal obesity measures.

RESULTS

Among premenopausal Whites, heavier childhood relative weight was associated with decreased cancer risk [odds ratio (OR) 0.48 95 % confidence interval 0.33-0.70]. Among premenopausal Blacks, greater adult waist circumference and waist-to-hip ratio (WHR) were associated with increased risk [waist OR 1.40 (1.00-1.97) and high tertile WHR OR 2.03 (1.29-3.19)], with associations for WHR in a similar direction in Whites. Among postmenopausal women, recalled body size was not associated with risk, except for increased risk associated with adult weight gain among White non-hormone therapy users. ER/PR status and hormone therapy use also modified other associations.

DISCUSSION

In this population, greater adult BMI was not associated with increased breast cancer risk, but some measures of early-life body size and abdominal obesity were associated with risk.

Disparities in breast cancer outcomes between Caucasian and African American women: a model for describing the relationship of biological and nonbiological factors

Breast cancer is the most common malignancy in women in the United States but significant disparities exist for African American women compared to Caucasian women. African American women present with breast cancer at a younger age and with a greater incidence under the age of 50 years, develop histologically more aggressive tumors that are at a more advanced stage at presentation, and have a worse disease-free and overall survival than Caucasian women. The biological characteristics of the primary tumor play an important role in determining the outcome of the disparity, and significant differences have been identified between African American and Caucasian breast cancer in steroid receptor and growth factor receptor content, mutations in cell cycle components, chromosomal abnormalities, and tumor suppressor and other cancer genes. The consequences of the biological factors are influenced by a variety of nonbiological factors, including socioeconomic, health care access, reproductive, and confounding factors. The nonbiological factors may act directly to enhance (or inhibit) the consequences of the biological changes, indirectly to facilitate outcome of the disparity, or as a cofounding factor, driving the association between the biological factors and the disparity. The prevention and management of the disparities will require an understanding of the relationship of biological and nonbiological factors. The present review was undertaken to promote this understanding by describing the biological basis of the four major disparities - early age of onset, more advanced stage of disease, more aggressive histologic changes, and worse survival - and the important relationship to the nonbiological factors. A model is proposed to provide a comprehensive view of this relationship, with the goal of facilitating an understanding of each disparity and the issues that need to be addressed to eliminate the disparity.

Women with inoperable or locally advanced breast cancer -- what characterizes them? A retrospective review of 157 cases

BACKGROUND

Breast cancer is the most common cancer among Danish women. Locally advanced breast cancer occurs in a relatively large proportion of all new primary breast cancer diagnoses and for unexplained reasons 20-30% of women with breast cancer wait more than eight weeks from the initial breast cancer symptom(s) before seeking medical advice.

MATERIAL AND METHODS

In this study, we performed a retrospective review of the medical records of patients referred to The Department of Breast Surgery, Rigshospitalet in Copenhagen in the period between 2006 and 2011, to characterize women presenting with breast cancer either larger than 5 cm or locally advanced breast cancer/inoperable breast cancer (LABC/IOBC). The aim of the study was to characterize these women concerning age, social status, co-morbidity, defined anamnestic parameters concerning breast history and delay in seeking medical advice, to explore whether common traits among these parameters could be identified which could account for the late diagnosis.

RESULTS

We identified 157 cases. The median age of our cohort was 67 years (range 30-98) and did not differ from all women with breast cancer, but with a high risk of severe medical co-morbidity, psychiatric co-morbidity or dementia. However, 42% did not reveal any history of a psychiatric or somatic co-morbidity did not take psychoactive drugs and had no previous benign breast disorder. They were living in their own homes, were married, did not suffer from dementia, could have a first-degree relative with a history of breast cancer, but still presented with breast cancer characterized as LABC/IOBC, without any apparent reason. Among these 42%, more than half had neglected their obvious symptoms of breast cancer.

Factors associated with receipt of breast cancer adjuvant chemotherapy in a diverse population-based sample

PURPOSE

Disparities in receipt of adjuvant chemotherapy may contribute to higher breast cancer fatality rates among black and Hispanic women compared with non-Hispanic whites. We investigated factors associated with receipt of chemotherapy in a diverse population-based sample.

PATIENTS AND METHODS

Women diagnosed with breast cancer between August 2005 and May 2007 (N = 3,252) and reported to the Detroit, Michigan, or Los Angeles County Surveillance, Epidemiology, and End Results (SEER) registry were recruited to complete a survey. Multivariable analyses examined factors associated with chemotherapy receipt.

RESULTS

The survey was sent to 3,133 patients; 2,290 completed a survey (73.1%), and 1,403 of these patients were included in the analytic sample. In multivariable models, disease characteristics were significantly associated with the likelihood of receiving chemotherapy. Low-acculturated Hispanics were more likely to receive chemotherapy than non-Hispanic whites (odds ratio [OR], 2.00; 95% CI, 1.31 to 3.04), as were high-acculturated Hispanics (OR, 1.43; 95% CI, 1.03 to 1.98). Black women were less likely to receive chemotherapy than non-Hispanic whites, but the difference was not significant (OR, 0.83; 95% CI, 0.64 to 1.08). Increasing age (even in women age < 50 years) and Medicaid insurance were associated with lower rates of chemotherapy receipt.

CONCLUSION

In this population-based sample, disease characteristics were strongly associated with receipt of chemotherapy, indicating that clinical benefit guides most treatment decisions. We found no compelling evidence that black women and Hispanics receive chemotherapy at lower rates. Interventions that address chemotherapy use rates according to age and insurance status may improve quality of systemic treatment.

Elevated PCNA+ tumor-associated macrophages in breast cancer are associated with early recurrence and non-Caucasian ethnicity

African American and Hispanic women develop more triple negative breast cancer at younger ages than Caucasian women. The frequently observed association between race and socioeconomic status (SES) has confounded our understanding of the outcomes disparities seen in these groups. Given the association between inflammatory cells and high-grade, triple negative tumors, we sought to investigate whether differences in the presence of these cells varies by race. We evaluated breast tumor specimens for the presence PCNA+ tumor-associated macrophages (TAMs) in consecutive cases from a county hospital serving primarily un- or under-insured patients. All patients in this cohort had elevated PCNA + TAM levels. Higher PCNA + TAM counts were associated with hormone receptor (HR) negative tumors and non-Caucasian ethnicity. Hispanic women specifically had significantly higher PCNA + TAM counts than Caucasian patients and shorter disease-free survival. These findings implicate immune function in the development of aggressive breast cancer and suggest a possible link between SES and the inflammatory response.

A review of body size and breast cancer risk in Hispanic and African American women

Obesity is an epidemic in the United States, especially among Hispanics and African Americans. Studies of obesity and breast cancer risk have been conducted primarily in non-Hispanic whites. There have been few studies of the association between body mass index (BMI) or weight gain and the risk of breast cancer in minorities, and the results have been inconsistent. Because most studies are conducted primarily in non-Hispanic whites, the etiology of breast cancer in minorities is not well understood. The authors of the current report reviewed the literature on the association between obesity, weight, and weight gain and breast cancer in minorities using a combination of the Medical Subject Heading (MeSH) terms "obesity," "body mass index," "weight," "weight gain," "Hispanic," and "African American." Only publications in English and with both risk estimates and 95% confidence intervals were considered. Forty-five studies of body size and breast cancer risk in non-Hispanic whites were identified. After an exhaustive search of the literature, only 3 studies of body size and breast cancer were conducted in Hispanic women were identified, and only 8 such studies in African American women were identified. The results were inconsistent in both race/ethnicity groups, with studies reporting positive, inverse, and null results. Thus, as obesity rates among Hispanics and African Americans continue to rise, there is an urgent need to identify the roles that both obesity and adult weight gain play in the development of breast cancer in these minorities. Additional studies are needed to provide more understanding of the etiology of this disease and to explain some of the disparities in incidence and mortality.

Access to hematopoietic stem cell transplantation: effect of race and sex

BACKGROUND

The purpose of the current study was to determine whether the use of hematopoietic stem cell transplantation (HCT) to treat leukemia, lymphoma, or multiple myeloma (MM) differs by race and sex.

METHODS

The annual incidence of leukemia, lymphoma, and MM was estimated in the United States in people aged <70 years by race and sex using the Surveillance, Epidemiology, and End Results (SEER) cancer registry between 1997 and 2002 and US census reports for the year 2000. The annual incidence of autologous, human leukocyte antigen (HLA) identical sibling, and unrelated HCT performed in these groups was estimated using Center for International Blood and Marrow Transplant Research data from 1997 through 2002. Logistic regression analysis was used to calculate the age-adjusted odds ratio (OR) of receiving HCT for Caucasians versus African Americans and for men versus women.

RESULTS

The likelihood of undergoing HCT was found to be higher for Caucasians than for African Americans (OR, 1.40; 95% confidence interval [95% CI], 1.34-1.46). This difference existed for each type of HCT: autologous (OR, 1.24; 95% CI, 1.19-1.30), HLA identical sibling (OR, 1.59; 95% CI, 1.46-1.74), and unrelated donor (OR, 2.02; 95% CI, 1.75-2.33). Overall, men were more likely than women to receive HCT (OR, 1.07; 95% CI, 1.05-1.1 [P<.0001]); however, this difference was found to be significant only for autologous HCT (OR, 1.10; 95% CI, 1.07-1.13 [P<.0001]).

CONCLUSIONS

HCT is more frequently used to treat leukemia, lymphoma, and MM in Caucasians than in African American individuals. African Americans have lower rates of both autologous and allogeneic HCT, indicating that donor availability cannot fully explain the differences. Women are less likely than men to receive autologous HCT for reasons unexplained by age or disease status.

Clinicopathologic presentation of Asian-Indian American (AIA) women with stage 0, I & II breast cancer

Although numerous studies have looked at cancer incidence and survival in Asian Indian-American (AIA) patients, there is a paucity of data regarding clinicopathologic presentation of cancer in this ethnically diverse population. After receiving IRB approval, AIA patients of Indian and Pakistani descent who presented with Stage 0, I, & II breast cancer to our facility were identified. Charts were extracted for clinical and pathologic variables in addition to outcomes data. Standard statistical analyses were performed using SAS (v 9.1). The population (n = 50) consisted of 86% Indian (n = 43) and 14% Pakistani (n = 7). The median age at diagnosis was 52 (range 25-79). Sixty-three percent of tumors were detected after discovery of a palpable mass while 36% had a mammographically detected mass. Stage 0, I & II distribution was 14, 42 and 44%, respectively. The median tumor size was 1.5 cm (range 0.2-4.5 cm). ER, PR, and HER2 were positive in 69, 67, and 24% of AIA patients, respectively; 21% were triple-negative. Treatment data shows that 60% underwent lumpectomy (n = 29), 39% underwent mastectomy (n = 19), 74% received hormonal therapy (n = 26) and 55% received chemotherapy (n = 30). To our knowledge, this is the first detailed report of the clinicopathologic presentation of Asian-Indian American women with breast cancer at a single institution. Of note, AIA women were more likely to present with palpable masses and at a younger age. This differs from Caucasian women and may indicate a social or cultural barrier to routine screening mammograms and possibly a biologically more aggressive tumor.

The interleukin-6 gene: a susceptibility factor that may contribute to racial and ethnic disparities in breast cancer mortality

Breast cancer prognosis differs among racial and ethnic groups. Though the incidence of breast cancer is lower in African-Americans than in Caucasians, mortality is higher. While socioeconomic, psychosocial, and lifestyle issues are undoubtedly important in such disparities, genetic factors that differ among populations and that are involved in the molecular pathways regulating tumor development may also play roles. In this communication, I summarize recent investigations of the gene encoding the pro-inflammatory cytokine interleukin-6 (IL-6), and suggest that this gene is a susceptibility factor that determines racial and/or ethnic differences in breast cancer survival. Published studies of a G/C polymorphism at nucleotide -174 within the promoter region of the IL-6 gene are consistent with this suggestion. This polymorphism alters expression of the cytokine. In addition, allele and genotype frequencies at the -174 site differ dramatically among racial and ethnic groups. Finally, the variant genotypes are associated with alterations in breast cancer survival. In all, these observations argue for additional studies of the IL-6 gene polymorphism as a predisposing genetic factor that contributes to racial and ethnic differences in breast cancer prognosis.

Racial differences in the expression of cell cycle-regulatory proteins in breast carcinoma

BACKGROUND

African-American (AA) women are more likely to be diagnosed with an advanced stage of breast carcinoma than are white women. After adjustment for disease stage, many studies indicate that tumors in AA women are more likely than tumors in white women are to exhibit a high level of cell proliferation and features of poor prognosis. The purpose of the current study was to compare tumor characteristics and cell cycle alterations in AA women and white women that might affect the aggressiveness of breast carcinoma.

METHODS

The study included 124 AA and 397 white women, ages 20-54 years. These women were enrolled in a case-control study in Atlanta, Georgia, between 1990 and 1992. Breast tumor specimens obtained from these women were centrally reviewed for histologic characteristics and evaluated for expression of estrogen and progesterone receptors (ER/PR), c-ErbB-2, Ki-67, p53, cyclin E, cyclin D1, p27, p16, pRb, and p21 by immunohistochemistry. Logistic regression models were used to assess the age- and stage-adjusted associations of various tumor characteristics with race.

RESULTS

The odds of a breast carcinoma diagnosis at a younger age and at a later stage were higher for AA women than for white women. After adjustment for disease stage and age at diagnosis, AA women also were found to have increased odds of having a higher-grade tumor, a higher mitotic index, marked tumor necrosis, ductal histology, loss of ER and PR, overexpression of cyclin E, p16, and p53 and low expression of cyclin D1 at diagnosis.

CONCLUSIONS

The observed differences between tumor specimens obtained from AA women and tumor specimens obtained from white women, independent of stage and age at diagnosis, indicated that race may be a determinant, or a surrogate for other determinants, of aggressive breast carcinoma and specific cell cycle defects.

Mammography screening and differences in stage of disease by race/ethnicity

OBJECTIVES

We examined the effect of routine screening on breast cancer staging by race/ethnicity.

METHODS

We used a 1990 to 1998 mammography database (N = 5182) of metropolitan Denver, Colo, women to examine each racial/ethnic cohort's incident cancer cases (n = 1902) and tumor stage distribution given similar patterns of routine screening use.

RESULTS

Regardless of race/ethnicity, women participating in routine screenings had earlier-stage disease by 5 to 13 percentage points. After control for possible confounding factors, White women were more likely to have early-stage disease compared with Black and Hispanic women.

CONCLUSIONS

Lack of screening coverage in certain racial/ethnic populations has often been cited as a reason for tumor stage differences at detection. In this study, correcting for screening did not completely reduce stage differentials among Black and Hispanic women.

The self-reported likelihood of patient delay in breast cancer: new thoughts for early detection

BACKGROUND

Delayed presentation of self-discovered breast symptoms influences stage of cancer at diagnosis and decreases breast cancer survival.

METHODS

A total of 699 asymptomatic women (black, white, and Latino), recruited in community settings and stratified by age, income, and educational level, were surveyed for their likelihood to delay (J-Delay scale) in the event of a breast symptom discovery. Models of likelihood were tested with logistic regression analyses.

RESULTS

A total of 166 women (23.7%) reported likelihood to delay. Lower income, lower educational level, self identification as Latino or black, experienced prejudice in care delivery, perceived lack of access to health care, fatalism about breast cancer, poor health care utilization habits, self-care behavior, spouse/partner and employer perceived constraints, problem-solving style, and a lack of knowledge of breast cancer's presenting symptoms were associated with likelihood to delay. A combined sample multiple logistic regression model correctly predicted 40.6% of women reporting a likelihood to delay, 94.9% of those not likely to delay, and 82.4% (551 of 669) of cases overall.

CONCLUSIONS

Self-reported likelihood of patient delay is measurable in advance of symptom occurrence, and this measure is consistent with behavioral and knowledge variables previously linked with advanced breast cancer at diagnosis.

Postmastectomy Reconstruction of the Previously Augmented Breast: Diagnosis, Staging, Methodology, and Outcome

Although many of the health and safety issues associated with breast augmentation have been thoroughly discussed over the past decade, the literature is remarkably silent regarding postmastectomy reconstruction of the previously augmented breast. A retrospective review of the senior author's reconstructive practice was performed for the years 1983 through March of 1999, revealing 21 women who underwent postmastectomy breast reconstruction after previous breast augmentation. For purposes of measuring aesthetic results, these 21 patients were matched to a carefully selected control group of 15 patients. They were also compared with other, larger populations, including 777 of the senior author's other breast reconstructions, the breast cancer registry at the Lombardi Cancer Center in Washington, D.C., and several large, published epidemiologic studies. The interval between the previous augmentation and the diagnosis of breast cancer ranged from 9 months to 18 years, with a mean of 9.3 years. None of the previous augmentation implants was ruptured at the time of mastectomy. Of the nine patients with previous subpectoral augmentation, cancer was detected mammographically in five (56 percent), whereas of the 12 patients with previous subglandular augmentation, cancer was first detected mammographically in only three (25 percent). This difference was not statistically significant (p = 0.2). Overall, eight of the study patients' tumors (38 percent) were first detected mammographically, which is similar to other published reports of breast cancer patients in the general population. Seventy-one percent of the 21 study patients were node-negative, which also compares favorably with other published series. Sixteen of the women with previous augmentation (76 percent) had purely prosthetic reconstructions. Flaps were used in the other five reconstructions (23 percent): three latissimus dorsi flaps (14 percent) and two transverse rectus abdominis musculocutaneous flaps (9 percent). All five flaps were used in patients who had undergone radiation therapy. Throughout the senior author's entire reconstructive practice history, transverse rectus abdominis musculocutaneous flaps were more frequently used [282 of 777 nonaugmented reconstructions (36 percent)], whereas latissimus dorsi flaps were less frequently used [17 of 777 nonaugmented reconstructions (2.2 percent)] (p < 0.001). The cosmetic results of the breast reconstructions in the previously augmented study group were generally good-to-excellent, with a mean score by blinded observers of 3.35 of a possible 4.0. These results were comparable to or better than those in the matched controls, who scored a mean of 3.0.

Racial and ethnic differences in access to medical care

The authors' review of the health services literature since the release of the landmark Report of the Secretary's Task Force Report of Black and Minority Health in 1985 revealed significant differences in access to medical care by race and ethnicity within certain disease categories and types of health services. The differences are not explained by such factors as socioeconomic status (SES), insurance coverage, stage or severity of disease, comorbidities, type and availability of health care services, and patient preferences. Under certain circumstances when important variables are controlled, racial and ethnic disparities in access are reduced and may disappear. Nonetheless, the literature shows that racial and ethnic disparities persist in significant measure for several disease categories and service types. The complex challenge facing current and future researchers is to understand the basis for such disparities and to determine why disparities are apparent in some but not other disease categories and service types.

Is race a poor prognostic factor in breast cancer?

BACKGROUND

African American breast cancer patients have a higher mortality rate than their Caucasian counterparts. The purpose of this study was to evaluate whether race is a poor prognostic factor in breast cancer survival after multiple other prognostic factors are taken into account.

STUDY DESIGN

The tumor registry data from two institutions between the years 1982 and 1995 were combined for the analysis. A total of 1,745 patients, including 1,297 African American and 448 Caucasian women, were available for analysis. Race, age, income, stage, histologic findings, type of operation, and treating institution were evaluated as possible key prognostic variables.

RESULTS

In a univariate Cox proportional hazards regression analysis, African American patients with breast cancer were 1.27 times more likely to die than Caucasians when death from disease was measured (p = 0.01, 95% confidence interval 1.03 to 1.47). When all factors were included in a Cox regression analysis, only the stage of disease at diagnosis, age, and whether the patient had a therapeutic surgical treatment were statistically significant. Race, income, hospital, and histologic findings were not significant, although they were significant when used in a univariate analysis.

CONCLUSIONS

Poor survival of African American breast cancer patients seems to be related to their advanced stage at presentation and young age. To improve survival in these women, efforts should be concentrated on aggressive screening at a young age to detect the disease at an earlier stage.

Age at presentation of African-American and Caucasian breast cancer patients

BACKGROUND

The purpose of this study was to compare the age at presentation of Black-American (Caribbean-American and African-American) and Caucasian breast cancer patients.

STUDY DESIGN

We reviewed the records of all breast cancer patients seen at King's County Hospital Center and SUNY Health Science Center at Brooklyn between 1982 and 1995. The patients were stratified based on ethnicity. Age distribution, median, and mean ages are compared for Black-American and Caucasian patients.

RESULTS

The median age, mean age, and standard deviation for 1,632 African-American patients was 54, 54.17, and 13.11 years, respectively, whereas for 671 Caucasians patients it was 62, 60.35, and 13.85 years, respectively. Using the Student's t-test for equality of means there is a statistically significant difference in the mean age of presentation for the 2 ethnic groups with a p < 0.001 and a 95% confidence interval for difference (4.960, 7.405). More than one-third (37.7%) of Black-American breast cancer patients present younger than 50 years of age compared with 24.7% for Caucasians.

CONCLUSIONS

The younger age at presentation of Black-American breast cancer patients ought to be considered while setting screening guidelines for that group of women.

Breast carcinoma tumor characteristics in black and white women

BACKGROUND

A significant disparity in mortality rates exists between black and white patients with breast carcinoma. This study was designed to compare breast carcinoma tumor characteristics by race and to examine the possible reasons for these differences.

METHODS

Female patients with an initial diagnosis of breast carcinoma between January 1, 1985 and December 31, 1993 were selected from the Yale-New Haven Hospital Tumor Registry for this retrospective cohort study. All black patients were eligible and white patients were selected randomly and matched to each black patient by year of diagnosis. Data were gathered from multiple sources including the hospital, the Connecticut Tumor Registry, and the U. S. Census. All pathology specimens were reviewed at Yale-New Haven Hospital.

RESULTS

The final cohort had 100 black and 300 white patients. The black patients tended to be younger than white patients at the time of diagnosis (mean age 55 years vs. 60 years; P = 0.001). A significant racial difference was noted in eight tumor characteristics: stage, size of the tumor, lymph node status, presence of necrosis, vascular/lymphatic invasion, ductal carcinoma in situ, perineural invasion, and progesterone receptor status. Although income, medical insurance coverage, and method of tumor detection explained some pathology differences, black patients still were more likely to have necrosis and a larger tumor size, even after adjustment.

CONCLUSIONS

Black patients with breast carcinoma tend to be diagnosed at a younger age and in a few important respects have different tumor characteristics compared with white patients, even after controlling for income, medical insurance coverage, and method of tumor detection after screening mammography. These differences may have etiologic and clinical implications.

Breast cancer mortality in black and in white women: a historical perspective by menopausal status

To examine racial/ethnic differences in breast cancer mortality over time by menopausal status, data from published U.S. Vital Statistics tables (1950-1992) and the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute (1973-1991) were used to calculate age-adjusted breast cancer mortality and incidence rates. Overall, breast cancer mortality rates for white women were relatively stable from 1950 to 1992. In contrast, breast cancer mortality rates for black women increased during this period. Among premenopausal women there was no difference in breast cancer mortality between black and white women from 1950 to about 1975. However, after 1975, mortality rates in black premenopausal women increased, whereas those in white women decreased. Among postmenopausal women, breast cancer mortality was substantially lower in blacks than in whites in 1950. Between 1950 and 1992, rates in blacks increased and eventually exceeded rates in whites, which remained stable during this period. This excess in breast cancer mortality in black women is not explained by changes in breast cancer incidence rates. There is an unexplained epidemic of breast cancer mortality in black women that appears to differ somewhat by menopausal status. Reasons for temporal increases in breast cancer mortality seen only among black women need to be identified, as do reasons for the heterogeneity of trends by menopausal status.

Racial differences in drug metabolism: an explanation for higher breast cancer mortality in blacks?

The risk of dying from breast cancer differs between racial groups, and the reason for this racial difference is unknown. In this paper, we hypothesize that racial differences in breast cancer mortality may be due to racial differences in the metabolism of drugs used to treat women with breast cancer. Racial differences in the metabolism and effectiveness of other commonly used drugs have been described, and these differences are thought to result from genetic differences in the cytochrome P450 enzyme system. Tamoxifen, widely used for breast cancer treatment, is metabolized by the cytochrome P450 system. Preliminary evidence from human studies suggests that this agent is less effective in non-whites than whites; however, more definitive studies are needed. A better understanding of racial differences in cytochrome P450 drug metabolism and subsequent effectiveness will lead to better breast cancer treatment for all women.

Racial differences in breast cancer survival: the interaction of socioeconomic status and tumor biology

OBJECTIVE

Our purpose was to evaluate the effect of sociodemographic and clinical variables on survival rates of African-American and white women with breast cancer.

STUDY DESIGN

Between 1988 and 1992 the Metropolitan Detroit Cancer Surveillance System Identified 10,502 women (82% white and 18% African-American) in whom invasive breast cancer was diagnosed. Cox proportional hazards regression was used to estimate the relative risk of death for African-Americans compared with whites after controlling for variables believed to influence survival.

RESULTS

African-American women were more likely than white women to have tumors that were of a more advanced stage, a higher grade, and hormone receptor-negative. After controlling for age, tumor size, stage, histologic grade, census-derived socioeconomic status, and the presence of a residency training program at the treatment hospital, the relative risk of dying for African-Americans compared with whites was 1.68 (95% confidence interval, 1.27-2.23) for women less than 50 years of age, and 1.33 (95% confidence interval, 1.13-1.56) for women older than 50 years of age.

CONCLUSIONS

Known factors that predict survival differences between African-Americans and whites are more prevalent among women less than 50 years of age, emphasizing the need to focus more attention on public health efforts directed toward younger women.

Breast cancer in African American women: epidemiology and tumor biology

This review of published data on the epidemiology, pathology, and molecular biology of breast cancer in African American women seeks to identify how the etiology and presentation of the disease differ from those in white women. The crossover from higher to lower age-specific incidence rates in African American women at age 45 cannot be explained by current data on the distribution of risk factors. Data from six case-control studies suggest that the relative risks associated with both established and probable breast cancer risk factors are similar in African American and white women. Lower survival in African American compared to white women is primarily attributable to diagnosis at a later stage. However, evidence from a number of studies suggests that tumors in African American women may exhibit a more aggressive phenotype, which could also contribute to the survival disparity. Tumors in African American women are more likely to occur at a younger age, to be poorly differentiated and estrogen receptor negative, and to exhibit high grade nuclear atypia, more aggressive histology (more medullary and less lobular), and higher S-phase. Overexpression of p53 and erbB-2 occurs with similar frequency in African American and white women, although limited data suggest the former may exhibit different p53 mutation spectra. One study found high risk associated with a specific CYP1A1 polymorphism in African American but not white women. Additional studies of molecular differences in African American and white women are needed, with multifactorial assessment of the independent effects of molecular and conventional risk attributes.