Ethnicity and birthplace in relation to tumor size and stage in Asian American women with breast cancer.

OBJECTIVES: This study examined whether Asian American women with breast cancer have tumor characteristics associated with delayed detection of their disease. METHODS: Breast cancer size and stage were examined in relation to subjects' ethnic group and birthplace, on the basis of Surveillance, Epidemiology, and End Results program data. RESULTS: Asian-born Asian American women with breast cancer had a greater proportion of tumors larger than 1 cm at diagnosis (79%) than did US White women (70%) (P < .001). In contrast, the proportion of tumors larger than 1 cm among Asian American women born in the United States (67%) did not differ significantly from that among US White women. CONCLUSIONS: Lower utilization of breast cancer screening by Asian-born Asian American women is probably responsible for their greater proportion of tumors larger than 1 cm relative to US White women in the study population. Interventional measures should be taken to increase the use of mammographic screening by first-generation Asian American women.