Comparative analysis of clinicopathologic features, treatment, and survival of Asian women with a breast cancer diagnosis residing in the United States

Background: It has been established that disparities by ethnicity in the rates of breast cancer diagnoses and disease-specific survival (DSS) exist in the United States. However, few studies have assessed differences specifically between Asians and other ethnic groups or among Asian subgroups. Methods: The authors used the Surveillance, Epidemiology, and End Results database to identify patients who were diagnosed with invasive breast cancer between 1988 and 2008. Clinicopathologic features, treatment, and DSS rates were compared among broad ethnic groups and among Asian subgroups. Results: In total, there were 658,691 patients in the study, including 511,701 non-Hispanic white (NHW) women (77.7%), 57,890 black women (8.8%), 45,461 Hispanic white (HW) women (6.9%), and 43,639 Asian women (6.6%). The Asian cohort was divided into the following subgroups: Filipino, Chinese, Japanese, Indian/ Pakistani, Korean, Vietnamese, Hawaiian/Pacific Islander, and other. Patients in all the Asian subgroups, except Japanese, were younger at diagnosis than NHW patients. After adjustment for disease stage, Japanese patients diagnosed with stage I through III disease had better DSS rates than patients in the NHW group or in the other Asian subgroups. Hawaiian/Pacific Islander patients with stage III or IV disease had worse DSS rates than NHW patients and patients in the other Asian subgroups. All other Asian subgroups had DSS rates similar to the DSS rate in the NHW group. Conclusions: The current results indicated that disparities exist for Asian women with breast cancer who reside in the United States compared with NHW groups and among Asian subgroups. Differences in presenting clinicopathologic features may affect DSS rates, suggesting that further investigation of these disparities is warranted to increase early detection and treatment for specific subgroups.