Breast Cancer in Women of African Descent (eBook)

Chapter 1: Burden of Breast Cancer in Developing and Developed Countries; D. Max Parkin Chapter 2: Genetics of Breast Cancer in Women of African Descent: An Overview; Offiong Francis Ikpatt and Olufunmilayo I. Olopade Chapter 3: Biology Of Breast Cancer: Molecular and Pathologic Features of Ductal Neoplasia of the Breast: Racial Considerations; David F. Chhieng, Andra R. Frost, Lynya I. Talley, William E. Grizzle Chapter 4: Screening and Early Detection of Breast Cancer in Women in Africa and the Middle East; B.L. Rapoport Chapter 5: Breast Cancer At Diagnosis in Women of Africa and the Middle East; Hussein M. Khaled Chapter 6: Breast Cancer Aggressiveness in Women of African Descent; Paul H. Levine and Carmela Veneroso Chapter 7: Radiotherapy of Breast Cancer; Olusegun Agboola Chapter 8: Adjuvant Therapy of Breast Cancer; Christopher K. O. Williams and Carla Falkson Chapter 9: Endocrine Therapy of Breast Cancer; Kathrin Strasser-Weippl and Paul E. Goss Chapter 10: Palliative Care for Breast Cancer in the African-American Population; Joseph O’Donnell Chapter 11: Outcome of African American Women with Breast Cancer in Cooperative Group Clinical Trials; Joseph M. Unger, Stephanie Green and Kathy S. Albain Chapter 12: Traditional Medicine in Breast Cancer Management with a Focus on the Chinese Integrative Approach; Steven K. H. Aung Chapter 13: Impact of Culture, Education and Socioeconomic Status; Rhonda S. Moore Chapter 14: Barriers to Successful Management of Breast Cancer; Christopher K.O. Williams

"Chapter 11 OUTCOME OF AFRICAN AMERICAN WOMEN WITH BREAST CANCER IN COOPERATIVE GROUP CLINICAL TRIALS (p. 267-268)

1. INTRODUCTION

African American women with breast cancer have markedly higher population mortality in the United States compared to either whites or all races combined (1). The U.S. age-adjusted death rate from invasive breast cancer was approximately 32% higher in African American women than in white women according to data from the Surveillance and Epidemiology and End Results program (2). The disparity in mortality rates from breast cancer has been growing since 1980, when mortali ty rates for both groups were similar. In contrast, the incidence of breast cancer is somewhat higher in whites than in African Americans.

Reports from single institution clinical trials and/or population-based databases show mixed results regarding whether race is an independent adverse predictor of survival for African American women with breast cancer. Where there are differences, they are typically ascribed to disparities in baseline disease characteristics such as stage at presentation, socio ­economic status, and access to care (3-5). Accounting for stage is routinely performed in population based studies; adjusting for socio-economic status (often as a surrogate for access to care) is typically more difficult, due to the hesitation among patients to report (and therefore researchers to request) such factors as income and education. A recent review by Cross et al. grouped the historical literature pertaining to studies of the effect of race on outcome by whether socio-economic status was included in the analysis as an adjustment variable (6).

Among the 13 studies which included socio-economic status as an adjustment variable, three studies (23%) found race to be a significant predictor of survival. Among the 18 studies without socio-economic status included, six (33%) found that race was a significant predictor of survival. Interestingly, if the studies that compared African Americans to whites are split in half according to sample size, seven of the 15 studies (47%) with large sample size (N) 1500) showed significant results, whereas only 2 of the 16 studies (13%) with small sample size (N<=1500) showed significant results, suggesting the limitations of underpowered analyses.

Cross concluded that between race and socio-economic status, socio-economic status is the more important predictor of outcome in breast cancer. In contrast, Newman et ai, in a meta-analysis of 14 studies comprising 10,001 African American patients and 42,473 white patients, found that African American race was an independent predictor of adverse survival even after accounting for socioeconomic status (7). African Americans had a 22% increased risk of mortality compared to whites (HR=1.22, 95% CI: 1.13-1.30). Newman suggested that biological differences between African Americans and whites, whether directly or in association with other factors, may play a role in breast cancer outcome."