Among women with the BRCA1/2 mutations, those who have been pregnant, given birth, not smoked, and/or have not taken oral contraceptives experience a delay in onset of a diagnosis of breast cancer. These findings may aid in determining optimal preventative or screening strategies according to life style variables for women with these mutations. These results were recently published in the journal Molecular Genetics and Genomic Medicine.
According to the Centers of Disease Control and Prevention (CDC), approximately one out of every 500 women in the United States has a mutation within either their BRCA1 or BRCA2 gene. Those with mutations in these genes, referred to as BRCA1/2 mutation carriers, have a 50% risk of developing breast cancer, and a 30% risk of developing ovarian cancer by the time they are 70 years of age. 1
Due to these increased risks, women who are BRCA1/2 mutation carriers can undergo frequent screening to detect cancer in its earliest and most treatable stages, or undergo surgery to remove the breasts and/or ovaries to drastically reduce the risk of developing these types of cancers.
Researchers also continue to explore possible life style variables that might contribute to the development or age of onset of breast or ovarian cancer among BRCA1/2 mutation carriers.
A recent study was conducted to evaluate possible associations between reproductive and life style factors in regards to the age of onset of a diagnosis of breast cancer among 197 BRCA1/2 mutation carriers.
- Overall, the following individual variables were associated with an earlier onset of breast cancer: smoking; no prior pregnancies or births; and oral contraceptive use.
- Women in this study born during or after 1965 tended to have fewer pregnancies and a higher rate of contraceptive use.
- Among women born before 1965, the average age of breast cancer diagnosis was 58 years.
- Among women born during or after 1965, the average age of breast cancer diagnosis was 42 years.
The researchers concluded that life style choices, particularly reproductive factors, influences the age of breast cancer diagnosis among BRCA1/2 mutation carriers. These results can help support optimal breast cancer screening and/or preventive options for these women and their healthcare providers.
- Centers for Disease Control and Prevention (CDC). BRCA Gene Mutations. Available at: http://www.cdc.gov/cancer/breast/young_women/bringyourbrave/hereditary_breast_cancer/brca_gene_mutations.htm?s_cid=byb_SEM_pd_007. Accessed April 14, 2016.
- Rieder V, Salama M, Glockner L, et al. Effect of lifestyle and reproductive factors on the onset of breast cancer in female BRCA 1 and 2 mutation carriers. Molecular Genetics and Genomic Medicine. doi: 10.1002/mgg3.191. eCollection 2016.