Racial Disparity in Breast Cancer Mortality

Grant #: Research Grant
PI Name: Smith-Bindman R
Title: Racial Disparity in Breast Cancer Mortality
Institute: California Breast Cancer Research Fund

Background: African American women have lower breast cancer incidence, yet higher breast cancer mortality rates and lower survival rates than white women. Additionally, the mortality gap has been increasing. Between 1989 and 1998, breast cancer mortality rates dropped 20% among white women, but only 3% among African American women, where the overall mortality rates were already higher. Hispanic, Asian, Pacific Islander, Hawaiian, and Native American women also have not seen the same improvements in mortality over the last decade as have been seen in white women.

Hypothesis: Racial and ethnic disparities in breast cancer mortality can be explained by differences in tumor biology, screening, diagnosis, treatment, and patient experiences with the health care system.

Objectives/Aims: To disentangle reasons for the racial disparity in breast cancer mortality, the investigators will (1) Identify racial/ethnic differences in the screening mammography utilization prior to breast cancer diagnosis, and the proportion of tumors diagnosed only once they became symptomatic (2) Identify racial/ethnic differences in breast cancer rates among similarly screened women (3) Identify racial/ethnic differences in breast cancer tumor characteristics at detection, such as size and stage (4) Identify, among women with similar tumor stage, racial/ethnic differences in breast cancer treatments (ex. type of surgery or receipt of lymph node dissection) and in the percentage of women who receive sub-standard care (5) Identify significant predictors of breast cancer survival, including intensity of mammographic screening, stage of disease at diagnosis, timeliness of breast cancer diagnosis and treatment, adequacy and type of breast cancer treatment, as well as age, race/ethnicity, and other sociodemographic variables (6) Identify prominent themes in breast cancer experiences (e.g., barriers to treatment, reasons for not seeking treatment, and reasons for late presentation for care) through qualitative semi-structured interviews with a multi-ethnic sample of women (N=200) who were diagnosed with regional or metastatic breast cancer between 2000 - 2002 in Northern California.

Methods: The investigators propose to analyze data from two large ethnically and racially diverse, population-based cohorts to identify racial/ethnic differences in the use of screening mammography, tumor characteristics at detection, breast cancer treatments, and breast cancer survival. The two datasets include women of different ages, from different geographical regions, and have different, complementary strengths. Additionally, the investigators propose to conduct structured qualitative interviews of women who were diagnosed with regional or metastatic breast cancer and identified through the Northern California Cancer Center to identify additional factors associated with late presentation for care, and different treatment experiences.