Risk of cancer-specific, cardiovascular, and all-cause mortality among Asian and Pacific Islander breast cancer survivors in the United States, 1991-2011.

Pooja A. Solanki,Naomi Y. Ko,Gregory S. Calip,Dima M. Qato

doi:10.1186/s40064-016-1726-3

Abstract

Asian and Pacific Islander (API) women in the United States (U.S.) are a heterogeneous group reported to have better prognosis after breast cancer (BC) compared to their Non-Hispanic White (NHW) counterparts. Few studies have examined differences in BC survival between individual API ethnic groups. We conducted a retrospective cohort study of 462,005 NHW and 44,531 API women diagnosed with incident, stage I–III BC between 1991 and 2011 in the Surveillance, Epidemiology and End Results (SEER) 18 registries. SEER-reported API ethnicity was grouped as Chinese, Japanese, Filipino, Hawaiian, Korean, Vietnamese, Asian Indian and Pakistani, and Pacific Islander. Multivariable Cox proportional hazards models were used to estimate hazard ratios (HR) and 95 % confidence intervals (CI) for risk of BC-specific, cardiovascular and all-cause mortality comparing API to NHW women. We also estimated mortality risk comparing U.S.-born to non-U.S.-born women. Compared to NHW women, API women overall had lower BC-specific, cardiovascular and all-cause mortality. BC-specific mortality risk was lowest among Japanese women (HR 0.69, 95 % CI 0.63–0.77). Other women had similar (Filipino, HR 0.93, 0.86–1.00; Hawaiian, HR 1.01, 0.89–1.17) or greater (Pacific Islander, HR 1.44, 1.17–1.78) risk of BC-specific death. Compared to non-U.S. born API women, findings were suggestive of increased cardiovascular (HR 1.12, 1.03–1.20) and all-cause mortality (HR 1.29, 1.08–1.54) among U.S.-born API women. Mortality risk varies greatly between BC survivors from different API backgrounds. Further research is warranted to understand these disparities in BC survivorship and the social and cultural factors that possibly contribute to greater mortality among later-generation API women born in the United States.

Highlights

Current understanding of breast cancer epidemiology among Asian women is limited due to the aggregation of data on Asian race and ethnicity
Study population and data sources We conducted a retrospective cohort study of women diagnosed with a first primary invasive, stage I–III breast cancer between January 1, 1991 and December 31, 2011 identified through twelve population-based cancer registries in the U.S that participate in the National Cancer Institute’s SEER Program [Surveillance Epidemiology and End Results (SEER) Program (2013)]—those serving the geographic areas of San Francisco-Oakland, Connecticut, Detroit, Hawaii, Iowa, New Mexico, Seattle-Puget Sound, Utah, Atlanta, San Jose-Monterey, Los Angeles, Rural Georgia, California, Kentucky, Louisiana, New Jersey and Greater Georgia
Among overall crude death rates by the end of follow-up, 23.8 % of Non-Hispanic White (NHW) women death due to any cause of which 42.0 % were due to breast cancer and 23.2 % were due to cardiovascular disease

Summary

Introduction

Current understanding of breast cancer epidemiology among Asian women is limited due to the aggregation of data on Asian race and ethnicity. Asian and Pacific Islander (API) communities compose the fastest growing racial/ethnic group in the United States (U.S.) (U.S Census Bureau 2012). This group originates from the earth’s largest continent and encompasses a heterogeneous population with respect to multiple races, immigration. Despite overall declines in BC over the past 5–10 years in other U.S racial and ethnic groups, incidence rates among some but not all API ethnic groups show increasing trends (American Cancer Society 2013). API women overall are reported to have the highest 5-year survival rates after breast cancer (91.4 %), but these data are unreliable given this large heterogeneous. Even less is known about long-term outcomes among API breast cancer survivors in the U.S

Objectives

Methods

Results

Discussion

Conclusion