New Australian study clarifies risk for faulty BRCA carriersJune 21st, 2017
Carriers of the faulty BRCA1 and BRCA2 genes have a higher risk of developing breast and ovarian cancers than the general population, and now a long-term study has provided a clearer view of the risk these women face.
The large Australian collaborative study found that by 80 years of age:
- Women with BRCA1 mutations have on average a 72% risk of developing breast cancer
- Women BRCA2 mutation carriers have a 69% risk of developing breast cancer
- The average lifetime risk of ovarian cancer is 44% for BRCA1 and 17% for BRCA2
Less than five percent of breast cancers are caused by an inherited mutation in the BRCA1 and BRCA2 genes, however, being able to identify the women at risk could save their lives.
“This study provides us with much more precise information about cancer risks for carriers, and will help personalise decision-making about the use and timing of prevention strategies such as medication, surgery and changing lifestyle factors,” says study co-author Professor Kelly-Anne Phillips from the Peter MacCallum Cancer Centre who is funded by the National Breast Cancer Foundation.
The study also discovered other important findings which could change the way prevention options are offered to women with these gene mutations, particularly older women. These include:
- Breast cancer risk was found to increase rapidly at a young age then remain at a constant high level for the rest of a woman’s life. It peaks in the 30s for BRCA1 mutation carriers and in the 40s for BRCA2 mutation carriers, but both types of carriers are at about the same high risk in later life
- There was no tail-off in risk as the women aged, overturning previous thinking that if a BRCA1 or BRCA2 mutation carrier turned 60 without a diagnosis then she is less likely to develop cancer subsequently
National Breast Cancer Foundation Director of Research Investment, Dr Alessandra Muntoni said, “The strength of this study is that it provides a more robust estimate of the level of risk in carriers of BRCA1 and BRCA2 gene mutations. There is now more certainty about their ongoing risk which helps to refine the framework for early detection, ultimately saving more lives.”