Ethnicity and breast cancer in Hawaii: increased survival but continued disparity

Abstract

Objectives: To examine ethnic variation in survival among 7722 women diagnosed with invasive breast cancer in Hawaii between 1990 and 2002 and to extend previous multivariate analyses by adding a new prognostic variable: estrogen receptor/progesterone receptor (ER/PR) status.

Design: Cox regression analysis of retrospective data.

Setting: Population-based data from the Hawaii Tumor Registry, which is part of the National Cancer Institute's Surveillance, Epidemiology, and End Results Program.

Participants: 7722 women in 5 ethnic groups--Caucasian, Chinese, Japanese, Filipino, and Native Hawaiian--diagnosed with invasive breast cancer between 1990 and 2002.

Main outcome measure: Survival, examining death from breast cancer and death from a cause other than breast cancer.

Results: Compared to Caucasians, significantly smaller proportions of Japanese and Chinese women and larger proportions of Native Hawaiian and Filipino women were diagnosed in later stages of disease and at earlier ages. The four minority ethnic groups had higher rates of ER+PR+ tumors than Caucasians. For both causes of death, ethnic disparities in survival were reduced, but still existed, after controlling for age, stage, and ER/PR status. Japanese had the highest rates of survival for either cause of death. Native Hawaiians and Filipinos had the lowest rates of survival for breast cancer, and Native Hawaiians and Caucasians had the lowest rates of survival for other causes of death.

Conclusions: Future studies should examine other reasons for continued ethnic differences in breast cancer survival in Hawaii, including socioeconomic status, access to insurance, adequacy of recommended screening frequency, comorbid conditions, treatment appropriateness and compliance, and genetic markers of tumor aggressiveness.