Breast Cancer Incidence Trends by Estrogen Receptor Status Among Asian American Ethnic Groups, 1990–2014

Abstract

Background Westernization and etiologic heterogeneity may play a role in the rising breast cancer incidence in Asian American (AA) women. We report breast cancer incidence in Asian-origin populations. Methods Using a specialized Surveillance, Epidemiology, and End Results-9 Plus API Database (1990–2014), we analyzed breast cancer incidence overall, by estrogen receptor (ER) status, and age group among non-Hispanic white (NHW) and AA women. We used age-period-cohort models to assess time trends and quantify heterogeneity by ER status, race and ethnicity, and age. Results Overall, breast cancer incidence increased for most AA ethnicities (Filipina: estimated annual percentage change [EAPC] = 0.96%/year, 95% confidence interval [CI] = 0.61% to 1.32%; South Asian: EAPC = 1.68%/year, 95% CI = 0.24% to 3.13%; Chinese: EAPC = 0.65%/year, 95% CI = 0.03% to 1.27%; Korean: EAPC = 2.55%/year, 95% CI = 0.13% to 5.02%; and Vietnamese women: EAPC = 0.88%/year, 95% CI = 0.37% to 1.38%); rates did not change for NHW (EAPC = -0.2%/year, 95% CI = -0.73% to 0.33%) or Japanese women (EAPC = 0.22%/year, 95% CI = -1.26% to 1.72%). For most AA ethnicities, ER-positive rates statistically significantly increased, whereas ER-negative rates statistically significantly decreased. Among older women, ER-positive rates were stable for NHW and Japanese women. ER-negative rates decreased fastest in NHW and Japanese women among both age groups. Conclusions Increasing ER-positive incidence is driving an increase overall for most AA women despite declining ER-negative incidence. The similar trends in NHW and Japanese women (vs other AA ethnic groups) highlight the need to better understand the influences of westernization and other etiologic factors on breast cancer incidence patterns in AA women. Heterogeneous trends among AA ethnicities underscore the importance of disaggregating AA data and studying how breast cancer differentially affects the growing populations of diverse AA ethnic groups.

The Landmark Series: The Breast Cancer Burden of the Asian American Population and the Need for Disaggregated Data

“…This is in contrast to an APC of 1.1% among Chinese (95% CI, 0.7–1.5) and Filipinas (95% CI, 0.7–1.4), with no significant increase observed for Japanese women during this period. Another study by Tuan et al 14 similarly found an increase in BC incidence rate between 1990 and 2014 among Chinese, South Asian (Asian Indians and Pakistani), Korean, Vietnamese, and Filipino women, with no such trends seen in NHW or Japanese women.…”

Korean American Immigrant Women’s Perceived Breast Cancer Risk and Prevention Beliefs: A Qualitative Study

“…Breast cancer is the second leading cause of death among Asian women in the United States, as well as the most commonly diagnosed cancer among women of Korean descent in America (American Cancer Society, 2016). Korean and Korean American women experience one of the highest rates of breast cancer incidence among Asian American women (Torre et al, 2016; Tuan et al, 2020). Yet, women of Korean descent have biannual mammography rates ranging from 36% to 65% which are lower than most other racial groups in the United States (American Cancer Society, 2016; S.…”

Mammogram Uptake among Korean American Women in the South: Do Health Beliefs Matter?

“…A study using the SEER Asian Pacific Islander Database (1990Database ( -2014 reported that Korean American women (KAW) have one of the highest breast cancer incidence rate increases (2.55% per year) compared to other Asian American women (Tuan et al, 2020). Despite the increasing burden of breast cancer diagnosis, screening rates among KAW remain low.…”