NEW YORK (Reuters Health) - Gene mutations that increase the risk of breast cancer, known as BRCA1 and BRCA2, may occur more commonly in Asian women than previously thought, new research suggests. Finding BRCA mutations can have important implications for breast cancer prevention and treatment.
According to the report, two prediction models, which rely on a woman's personal and family history of breast and ovarian cancer, often fall short in identifying Asian women likely to have BRCA1 and BRCA2 mutations.
Because of their availability free of charge through the Internet and their generally good performance, these models are widely used in the U.S. to guide testing.
"Our findings indicate that Asian-American women with BRCA mutations may not be referred for genetic testing as often as they should be," lead author Dr. Allison W. Kurian, at California's Stanford University, said in a press statement.
Kurian and co-researchers evaluated the two prediction models, known as BRCAPRO and Myriad II, in 200 Asian subjects and a similar group of 200 white subjects. The testing was performed at four cancer genetics clinics.
According to the report in the Journal of Clinical Oncology, both models accurately predicted the number of white mutation carriers. Among 25 women who had one of the mutations, 24 were predicted by BRCAPRO and 25 by Myriad II.
However, among 49 Asian women with a mutation, just 25 were predicted by BRCAPRO and 26 by Myriad II.
Only BRCAPRO discriminates between BRCA1 and BRCA2 mutation carriers, and genetic testing showed that Asian BRCA2 mutations carriers were six times more common than predicted by this model.
Further research is needed to better understand racial differences in the occurrence of BRCA mutations, the authors conclude.
SOURCE: Journal of Clinical Oncology, October 10, 2008.
