Breast cancer rates among Asian-Americans are steadily rising in contrast to other racial/ethnic groups, a new study suggests.
Researchers from the Cancer Prevention Institute of California reviewed data from 1988 to 2013 on breast cancer among women in California from seven Asian ethnic groups. These included Chinese, Japanese, Koreans, Filipinos, Vietnamese, South Asians (Asian Indians and Pakistanis), and Southeast Asians (Cambodians, Laotians, Hmong, Thai).
During the study period, all of these groups — except Japanese women — had an overall increase in breast cancer incidence. The largest increases were among Koreans, South Asians and Southeast Asians, the study authors said.
“These patterns warrant additional attention to public health prioritization to target disparities in access to care, as well as further research in identifying relevant breast cancer risk factors for specific breast cancer subtypes,” lead researcher Scarlett Lin Gomez said in an institute news release.
Among women over age 50, there were increases in all Asian-American ethnic groups. In women under 50, there were large increases among Vietnamese and other Southeast Asian groups.
Breast cancer rates among Asian-American women as a whole were lower than among white women. But the rates among Japanese and Filipino women younger than 50 were similar to rates for white women of the same age.
The researchers also found that HER2 breast cancer was more common among Korean, Filipino, Vietnamese and Chinese women than among white women. HER2 (human epidermal growth factor receptor 2) is a gene that plays a role in the development of breast cancer. The study authors noted this type of cancer tends to grow more quickly and spread more aggressively.
Gomez suggested that future research into breast cancer risk factors in Asian women might look at early life exposures and possible genetic susceptibility.
The study was published in the journal Breast Cancer Research and Treatment.
The U.S. National Cancer Institute has more on breast cancer.