Earlier research has consistently shown that racial and ethnic minority women born outside the United States are less likely to be diagnosed with breast cancer than their U.S.-born counterparts. A small study suggests this trend is changing for Asian-American women: Asian-American women who had immigrated to the United States had a higher risk of breast cancer than Asian-American women born in the United States.
The study was published in the Feb. 14, 2019, issue of Preventing Chronic Disease. Read the abstract of "Higher Breast Cancer Risk Among Immigrant Asian American Women Than Among US-Born Asian American Women."
How the study was done
The researchers looked at information from 570 women living in the San Francisco Bay Area, which is home to the highest concentration of Asian Americans in the United States outside Hawaii. Between 2005 and 2009, 132 of the women had been diagnosed with breast cancer and 438 had not.
The researchers divided the women into three groups:
- women born in the United States (166 women)
- women born outside the United States who had lived 50% or more of their lives in this country (166 women)
- women born outside the United States who had lived less than 50% of their lives in this country (238 women)
The researchers took into account the following breast cancer risk factors:
- pregnancy history
- a woman's age at the birth of her first child
- family history of breast cancer
- menopausal status
- whether a woman took hormone replacement therapy
- body mass index
The researchers then compared rates of breast cancer among the three groups of women.
The number of women diagnosed with breast cancer in each group was:
- 22 (17%) women born in the United States
- 56 (42%) women born outside the United States who had lived 50% or more of their lives in the United States
- 54 (41%) women born outside the United States who had lived 50% or less of their lives in the United States
Both groups of immigrant Asian-American women were much more likely to be diagnosed with breast cancer than Asian-American women born in the United States. Notably, immigrant Asian-American women who had lived 50% or more of their lives in this country were about three times more likely to be diagnosed with breast cancer than Asian-American women who were born in the United States.
What this means for you
The researchers said the study should be viewed as preliminary evidence and more research is needed to clarify the results.
If you're an Asian-American woman who was born outside the United States and immigrated here, you may want to talk to your doctor about this study. Ask what your personal risk of breast cancer is, how it is calculated, and whether it takes into account where you were born.
Right now, most doctors use some form of the Gail model, a standard breast cancer risk assessment tool, to calculate breast cancer risk. The Gail model assesses breast cancer risk based on a series of personal health questions that you and your doctor answer together. The questions ask about risk factors such as age, child-bearing history, family history of breast cancer, and breast biopsy results. Some more recent versions of the Gail model also ask about alcohol use, menopausal status, and body mass index. The result is a Gail score, which estimates the risk of developing invasive breast cancer in the next 5 years.
It also makes good sense to do all that you can to keep your risk of breast cancer as low as it can be. Some lifestyle choices you may want to consider are:
- maintaining a healthy weight
- exercising every day
- limiting or avoiding alcohol
- eating a healthy diet that’s low in processed foods, sugar, and trans fats
- not smoking
- breastfeeding, if you have the option to do so
To learn more about breast cancer risk and other options to keep your risk as low as it can be, visit the Breastcancer.org Lower Your Risk section.
Written by: Jamie DePolo, senior editor
Reviewed by: Brian Wojciechowski, M.D., medical adviser