A comparison of treatment outcomes for black patients and white patients with metastatic breast cancer. The Piedmont Oncology Association experience

Racial differences and disparities in cancer care and outcomes: where's the rub?

Despite a profusion of studies over the past several years documenting racial differences in cancer outcomes, there is a paucity of data as to the root causes underlying these observations. This article reviews work to date focusing on black-white differences in cancer outcomes, explores potential mechanisms underlying these differences, and identifies patient, physician, and health care system factors that may account for persistent racial disparities in cancer care. Research strategies to elucidate the relative influence of these various factors and policy recommendations to reduce persistent disparities are also discussed.

Racial disparities in being recommended to surgery for oral and oropharyngeal cancer in the United States

OBJECTIVES

To investigate the impact of race on the likelihood of patients being recommended for surgery after a diagnosis of oral and oropharyngeal cancer.

METHODS

A total of 68,445 cases of oral and oropharyngeal cancer were extracted from the 1988 to 2005 Surveillance, Epidemiology, and End Results (SEER) database. County-level rurality data and income data were merged using the US Department of Agriculture Rural-Urban Continuum Codes dataset and US Census Bureau Small Area Income & Poverty Estimates dataset. We used logistic regression analyses to investigate the impact of race on being recommended to surgery for oral and oropharyngeal cancer, adjusting for demographic, socioeconomic, and clinical factors. Stratified analyses were further conducted by tumor site and rural/urban status.

RESULTS

Recommendation to surgery varied significantly by race, with black patients less likely than white patients to be recommended to surgery for their oral and oropharyngeal cancer. The racial difference in recommendation to surgery varied significantly by age, geography, and tumor subsite. Racial disparities are most evident in lip and buccal cancer from rural areas (OR, 4.4; 95% CI, 2.6-7.5); and least evident in oropharyngeal cancer from urban areas (OR, 1.2; 95% CI, 1.1-1.3). The magnitude of the racial disparity is attenuated with increasing age.

CONCLUSIONS

We observed substantial racial disparities in surgery recommendation for oral and oropharyngeal cancer in the United States. Our results suggest the need to improve accessibility to better health care in racial minority groups, particularly in rural areas, and call for individual and institutional efforts to avoid physician bias related to the patient's sociodemographic characteristics in healthcare service.

Social determinants of Black-White disparities in breast cancer mortality: a review

Despite the recent decline in breast cancer mortality, African American women continue to die from breast cancer at higher rates than do White women. Beyond the fact that breast cancer tends to be a more biologically aggressive disease in African American than in White women, this disparity in breast cancer mortality also reflects social barriers that disproportionately affect African American women. These barriers hinder cancer prevention and control efforts and modify the biological expression of disease. The present review focuses on delineating social, economic, and cultural factors that are potentially responsible for Black-White disparities in breast cancer mortality. This review was guided by the social determinants of health disparities model, a model that identifies barriers associated with poverty, culture, and social injustice as major causes of health disparities. These barriers, in concert with genetic, biological, and environmental factors, can promote differential outcomes for African American and White women along the entire breast cancer continuum, from screening and early detection to treatment and survival. Barriers related to poverty include lack of a primary care physician, inadequate health insurance, and poor access to health care. Barriers related to culture include perceived invulnerability, folk beliefs, and a general mistrust of the health care system. Barriers related to social injustice include racial profiling and discrimination. Many of these barriers are potentially modifiable. Thus, in addition to biomedical advancements, future efforts to reduce disparities in breast cancer mortality should address social barriers that perpetuate disparities among African American and White women in the United States.

Racial differences in clinical outcomes from metastatic breast cancer: a pooled analysis of CALGB 9342 and 9840--Cancer and Leukemia Group B

PURPOSE

African American women are more likely to be diagnosed with metastatic breast cancer at the time of presentation than whites, and have shorter survival once diagnosed. This study examines racial differences in clinical outcomes in the setting of two large cooperative group randomized clinical trials.

PATIENTS AND METHODS

The study cohort consisted of 787 white (80%) and 195 African American (20%) patients with metastatic breast cancer enrolled in two successive Cancer and Leukemia Group B (CALGB) trials using taxanes in the metastatic setting. Differences in overall survival (OS), response incidence, and time to treatment failure (TTF) were examined by race. In addition, differences in the incidence of baseline and treatment-related toxicities were examined.

RESULTS

With 779 deaths (166 African Americans and 613 whites), median OS was 14.3 months for African Americans and 18.75 months for whites (hazard ratio [HR] = 1.37; 95% CI, 1.15 to 1.63). When adjusted for prognostic factors, African Americans had a 24% increase in the hazard of death compared with whites (HR = 1.24; 95% CI, 1.02 to 1.51). No significant differences in TTF or overall response to therapy were seen. No clinically significant toxicity differences were seen.

CONCLUSION

African Americans with metastatic breast cancer have an increased hazard of death compared with whites despite the receipt of similar per-protocol treatment, but experience no differences in TTF or overall response to therapy. We hypothesize that more direct and robust measures of comorbidities, and perhaps other factors such as receipt of subsequent therapy could help further explain the observed survival difference.

Urban/rural residence moderates effect of race on receipt of surgery in patients with nonmetastatic breast cancer: a report from the South Carolina central cancer registry

BACKGROUND

Surgical resection is the cornerstone of therapy in patients with nonmetastatic breast cancer. Previous studies have reported underuse of adjuvant therapy among African Americans (AA). This study explores the independent effect of race on surgical resection in a recent, population-based sample of breast cancer patients.

METHODS

All cases of nonmetastatic breast cancer reported to the our state Cancer Registry between 1996 and 2002 were identified and linked to the state Inpatient/Outpatient Surgery Files and the 2000 Census. Characteristics between Caucasian and AA patients were compared using Student's t and chi-square tests. Odds ratios (OR) of resection and 95% confidence intervals (CI) were calculated using logistic regression.

RESULTS

We identified 12,404 Caucasian and 3,411 AA women. AA patients were more likely to be younger, non-married, have greater comorbidity, reside in rural communities, be less educated, live in poverty, and be uninsured or covered by Medicaid (all P < 0.0001). AA patients were slightly less likely to undergo resection compared to Caucasian patients (94.9% versus 96.4%, P < 0.0001). An interaction effect between race and urban/rural patient residence was observed (P = 0.003). After controlling for other factors, the adjusted OR for resection for urban AA patients was 0.58 (95% CI 0.41-0.82). In contrast, race had no effect on resection among rural patients (OR = 1.02; 95% CI 0.70-1.47).

CONCLUSIONS

AA race is an independent predictor of underuse of surgery among urban patients with breast cancer, while rural residence is associated with underuse of surgery, irrespective of race. Interventions designed to optimize surgical cancer care should target these vulnerable populations.

Ethnic Disparities in Adjuvant Chemotherapy for Breast Cancer Are Not Caused by Excess Toxicity in Black Patients

BACKGROUND

Black patients with breast cancer may be at greater risk for chemotherapy-related hematologic toxicity than white patients because of lower baseline blood cell counts. We hypothesize that these baseline differences could lead to excess hematologic toxicity and greater modification of chemotherapy dosing in black patients and that this may contribute to the poorer survival observed in black patients with breast cancer compared with white patients with breast cancer.

PATIENTS AND METHODS

We performed a retrospective cohort study of black and white patients with breast cancer treated with adjuvant chemotherapy at an academic medical center over an 18-month period. Clinical chart review and pharmacy records were used to collect data on the following: modification of chemotherapy dose or administration; hematologic toxicity; blood cell counts before, during, and after therapy; occurrence of febrile neutropenia; use of prophylactic antibiotics; and use of granulocyte colony-stimulating factor in order to determine whether ethnicity was an independent predictor of these outcomes.

RESULTS

Among 23 black patients and 98 white patients with breast cancer treated with adjuvant chemotherapy, modification of chemotherapy administration occurred in 56 patients (46%). Modification was more common among black patients (65.2% vs. 41.8%; relative risk [RR], 1.56; P = 0.04). Black patients were more likely to receive reduced cumulative doses of adjuvant chemotherapy (RR, 2.49; P = 0.03).

CONCLUSION

Our findings suggest that hematologic tolerability of adjuvant chemotherapy is similar in black and white patients. Strategies aimed at improving psychosocial barriers to adjuvant therapy and at reducing surgical complications in black patients may improve overall breast cancer outcomes in this group.

Treatment choices and response rates in African-American women with breast carcinoma

BACKGROUND

Breast cancer mortality rates are higher among African-American women compared with white American women, yet little is known regarding ethnicity-related variation in patterns of primary surgical treatment, locoregional recurrence rates, and response to induction chemotherapy.

METHODS

The available literature was reviewed to evaluate outcome from breast-conservation therapy in African-American women and response rates to systemic therapy.

RESULTS

Breast-conservation therapy appears to be underused among African-American women, a pattern that is noted also among white women with breast carcinoma. Higher rates of locoregional recurrence are seen among African-American women regardless of whether they receive breast-conserving treatment or undergo mastectomy, and this appears to be a function of primary tumor biology. Response rates to appropriately delivered systemic therapy are similar for African-American patients and white patients.

CONCLUSIONS

Despite the apparent increased aggressiveness of disease seen in African-American women with breast carcinoma, patterns of response to local and systemic therapy are similar to the patterns seen in white women with breast carcinoma.

Characterisation of benign lesions and carcinomas of the female breast in a sub-Saharan African population

Carcinoma of the breast is the second most frequent tumour in African females. Breast carcinomas in African females appear about a decade earlier and follow a more aggressive clinical course than those in developed countries. To elucidate this difference we investigated 63 biopsied benign lesions of the female breast for their potential to malignant progression. We also performed histologic typing and grading of 184 female breast carcinomas received at the Muhimbili University Hospital in Dar es Salaam, Tanzania. Fibrocystic disease and fibroadenomas were the most frequent lesions. The majority of patients with fibrocystic disease had no proliferative lesion and thus were not at a significantly increased risk of developing breast carcinomas. For fibroadenomas, no indication for precancerous lesions was found. The vast majority of breast carcinomas investigated were invasive. As a striking feature, the majority of those studied (66%) were of the non-special type (NST), displaying a more aggressive behaviour than the remaining tumours of the special type (ST). In the group of ST tumours, cribriform types constituted 41% of the cases which may be a special feature of the carcinomas in African females. Among the NST, the tumours were either of grade II or grade III, whereas in ST, 25% of the cases were of grade I. Since histology observed in this study is comparable to that seen in patients from the Western society, late hospital presentation with advanced tumour stages may be a major reason for differences in clinical behaviour between African and Western females. A genetic factor, however, may be an important contributing factor.

Breast carcinoma survival analysis for African American and white women in an equal-access health care system

BACKGROUND

This retrospective review of breast carcinoma cases in the Department of Defense (DoD) Central Tumor Registry evaluated differences in survival patterns between African American and white women treated in U.S. military health care facilities. The study examined the effects of age, stage of cancer, tumor size, grade, lymph node involvement, waiting time between diagnosis and first treatment, marital status, military dependent status, alcohol usage, tobacco usage, and family history of cancer.

METHODS

Researchers reviewed the tumor registry records of 6577 women (5879 whites and 698 African Americans) diagnosed with breast carcinoma. The patients, ages 19-97 years, were diagnosed between 1975 and 1994. A hazard ratio (relative risk of mortality) model compared African American and white patients, adjusting for various combinations of covariates; impact of independent variables on the risk of death; prognostic factors significantly associated with survival; disease free and overall survival times; effects of ethnicity, stage, and age on survival; and trends in stage at diagnosis. A P value (2-sided) of less than 0.05 was considered statistically significant.

RESULTS

After adjustment for age, the risk of death was 1.45 (95% confidence interval [CI], 1.20-1.76) times greater for African American women than for white women. Adjustment for stage reduced the risk to 1.41 (95% CI, 1.16-1.70); further adjustment for demographic variables and most clinical variables had no effect. Still, African American women treated in the military health care facilities had a better survival rate than African American women represented in the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute. In our study, the 5-year risk of death, from any cause, was 1.37 for African American women with breast carcinoma; in other words, the mortality rate for African American women was 24.77% compared with 18.08% for white women. In the latest SEER data, the 5-year relative risk of death for African American women compared with white women is 1.86. The mortality rate in SEER is 34.2% for African American women and 18.4% for white women. The survival rate for white DoD beneficiaries is comparable to that for white women in SEER.

CONCLUSIONS

These observations suggest that ready access to medical facilities and the full complement of treatment options that are standard for all DoD patients improve survival rates for African American women. However, a significant unexplained difference in survival still exists between African American and white military beneficiaries.

Attitudes about breast cancer and mammography: racial, income, and educational differences

This study examined the effect of race, income, and education on perceived susceptibility to and control over breast cancer, perceived benefits of and barriers to mammography, and knowledge about breast cancer and mammography use, in addition to determining if predictors for mammography use differed between races. Self-reported mailed survey data were obtained from a convenience sample of 1083 church women (78% Caucasian, 22% African-American) > or = 50 years with no history of breast cancer. ANOVA identified higher susceptibility and lower knowledge scores for African-American women; higher knowledge scores for upper income women of both races; interactions between race and income for benefits and perceived control; and interactions between race and education for barriers. African-American women were more likely to regard fear of radiation as a barrier to mammography (OR = .34; CI = .20, .57) and were more likely to worry about getting breast cancer (OR = .50; CI = .30, .82). Caucasian women were more likely to regard cost as a barrier (OR = 2.36, CI = 1.27, 4.40). For both races, variables predictive of ever having a mammogram were perceived control (White: OR = .69, CI = .54, .88; Black: OR = .50, CI = .38, .92), perceived barriers (White: OR = .88, CI = .83, .95; Black: OR = .75, CI = .64, .88), and knowledge (White: OR = 1.18, CI = 1.04, 1.33; Black: OR = 1.28, CI = 1.02, 1.61). Perceived benefits was predictive only for Caucasians (OR = 1.71, CI = 1.42, 2.06). Racial differences in perceived barriers to mammography and findings about the knowledge differences related to race, income, and education provide direction for health education efforts. The significance of cost factors for Caucasian and low-income women suggest that access barriers remain despite increased use of mammography.

Breast cancer. Is ethnicity an independent prognostic factor for survival?

BACKGROUND

A survival difference between white and black females has been reported after diagnosis and treatment for breast carcinoma. Although multivariate analyses demonstrate that the survival difference is less or nonexistent when additional prognostic factors are considered, study results have been inconsistent. The objective of this study was to examine further the role of ethnicity as an independent prognostic factor for breast carcinoma survival among white and black females treated over a 30-year period.

METHODS

Among 3382 eligible white and black females who registered at M. D. Anderson Cancer Center (MDACC) from 1958 to 1987, ethnicity, age, socioeconomic status (SES), stage of disease, and treatment were examined. Data were obtained from the hospital tumor registry and survival was compared using actuarial life tables and multivariate Cox regression analyses.

RESULTS

Univariate analyses demonstrated that the survival difference between white and black females was significant, with black females having a 1.63 times higher risk of mortality at 5 years compared with white females (confidence interval (CI), 1.47-1.82), with ethnicity a significant predictor of survival (P < 0.001). After controlling for SES, stage, and treatment, the relative risk was 1.12 (CI, 1.00-1.25) and ethnicity was no longer a strong predictor of survival (P = 0.048).

CONCLUSIONS

In this hospital population, the white and black female survival difference, which was highly significant when only univariate analyses were considered, became marginally significant after controlling for other prognostic factors.

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.

Racial differences in survival of female breast cancer in the Detroit metropolitan area

BACKGROUND

In the United States, breast cancer survival is worse among African-American women compared with white women. This difference in survival is likely due to several factors, including tumor biology and/or access to care. In this analysis, we evaluated the effects of sociodemographic and clinical variables on differences in breast cancer survival among African-American and white women.

METHODS

The study population included 10,502 women (82% white, 18% African-American), diagnosed between 1988 and 1992 and identified through the Metropolitan Detroit Cancer Surveillance System, a member of the Surveillance, Epidemiology and End-Results (SEER) Program. Cox proportional hazards regression was used to estimate the relative risk of death comparing African-American women with white women after controlling for variables believed to influence survival.

RESULTS

The mean age at diagnosis was 61 years and average length of follow-up was 34 months (range, 1-78 months). African-American women were more likely to present with regional or distant disease (45%) than were white women (37%). Although white women had better survival than African-American women during the first 4 years postdiagnosis (P < 0.0001), there were no significant differences in survival by race for women who lived longer than 4 years (P = 0.64). There was a significant interaction between age and race. The unadjusted relative risk of dying for African-American women compared with white women was 2.35 (95% confidence interval [CI], 1.88-2.93) for women younger than 50 years of age, and was 1.66 (95% CI, 1.46-1.88) for women age 50 years or older. After controlling for age, tumor size, stage, histologic grade, census-derived socioeconomic status, and residency training status, the relative risk was 1.68 (95% CI, 1.27-2.24) for women younger than 50 years of age and 1.33 (95% CI, 1.13-1.56) for women age 50 years and older. Adjustment for marital status, hospital size, and the proportion of Medicaid or Medicare discharges had no further effect on the relative risk.

CONCLUSIONS

Known factors that predict survival differences between African-American and white women are more prevalent among women younger than age 50.

Is metastatic breast cancer, refractory to usual therapy, curable?

Breast cancer with metastatic disease is presently incurable. Significantly shorter survival rates are seen in premenopausal women despite usual therapies when compared to survival rates in older women. Median survival rates of 24-30 months are documented in large-scale prospective clinical trials of previously untreated women with metastatic breast cancer regardless of the protocol employed (chemotherapy, hormone therapy). High dose chemotherapy followed by autologous stem cell rescue (bone marrow or peripheral blood) is associated with significant response and possibly improved survival in chemosensitive patients with metastatic disease without visceral metastases though with significant toxicities and cost (median survival rate of 20 months). Patients with refractory disease have dismal results regardless of therapy (median survival rates of 8-9 months in a number of prospective trials with or without stem cell rescue). The use of alpha-interferon in such patients has not improved response. Whole body hyperthermia is of benefit in the presence of liver metastases although median survival rate is in the range of 12 months. New treatment approaches with curative intent are clearly required. We report fifty-nine patients with metastatic breast cancer refractory to common therapies who were treated with whole body hyperthermia (40 degrees C) with low dose chemotherapy and immunomodulation: five presented with brain metastases; 13 with multiple bone metastases; 8 with liver metastases; 10 with lung metastases; and 23 with multiple soft tissue metastases. Fifteen were premenopausal; 44 postmenopausal. Twenty-three achieved complete remission. Fourteen have been sustained with patients remaining alive from 17-80 months (median, 40 months). Nine failed after 20-40 months of being disease-free (mean, 32 months).(ABSTRACT TRUNCATED AT 250 WORDS)

Care-seeking behavior with breast cancer symptoms in Caucasian and African-American women

Based on a theory of care seeking, the influences of psychosocial variables (anxiety, utility beliefs, norm, and habit) and facilitators (e.g., an identified practitioner) on care-seeking behavior with a breast cancer symptom were examined. Also, the influences of variables not identified by the theory (e.g., optimism and race) on care-seeking behavior were examined. Participants were Caucasian (n = 64) and African-American women (n = 71) with breast symptoms. Care seeking was measured by the days between symptom detection and contact with the health system. Habit was associated with promptness, utility beliefs were associated with delay, and anxiety interacted with having an identified practitioner to explain care seeking. Optimism and having a friend with a breast symptom also were associated with promptness. Race had neither direct nor interactive effects on care seeking.

Racial and marital status influences on 10 year survival from breast cancer

The association of race and marital status with survival during a 10 year period after a breast cancer diagnosis is described. The data for this study were obtained from the Metropolitan Detroit Cancer Surveillance System, a participant in the National Cancer Institute's SEER program. The study sample was 10,778 women (85.6% white and 14.4% black) diagnosed with incident invasive breast cancer between 1973 and 1978. Marital status was significantly associated with race, but had only a weak relationship with length of survival in a multivariate model predicting 10 year survival. However, race was strongly related to survival. African American women were significantly more likely than white women to die from breast cancer after controlling for age at diagnosis, marital status, tumor stage, histologic type, treatment status, and the interaction of age with stage. Ten years after being diagnosed with breast cancer, 38.2% of whites, compared with 33.3% of blacks were still living. These data confirm a body of literature which finds that blacks experience a shorter survival period following a cancer diagnosis than do whites. However, the relationship of marital status to cancer survival is still unclear and needs further study.