Faulty gene doesn't affect 'breast cancer survival'
12th January 2018 – Younger women diagnosed with breast cancer who carry a faulty BRCA gene are at no more risk of dying early than those without the mutation, according to a UK study.
Researchers say the findings suggest there is no imperative for women with breast cancer who carry a BRCA mutation to opt for double mastectomies soon after their diagnosis.
The actress Angelina Jolie underwent a preventative double mastectomy in 2013, aged 37, after learning she was at high risk of developing breast cancer due to a defective BRCA gene.
Breast and ovarian cancers
BRCA mutations are inherited and occur in either the BRCA1 or BRCA2 gene. The faulty gene increases the risk of a woman developing breast and ovarian cancers, with 45% to 90% of women with the mutation developing breast cancer during their lifetime, compared to roughly 12.5% of women in the general population.
The research team, led by the University of Southampton, used data from 2,733 young women in 127 UK hospitals who had been diagnosed with primary breast cancer before the age of 40.
- 89% had undergone chemotherapy
- 49% had had breast-conserving surgery
- 50% had undergone a mastectomy
- Fewer than 1% had no breast surgery
The women, who were recruited between 2000 and 2008, were monitored for an average of 8.2 years to discover more about their treatment, whether their cancer returned, or if they died.
During this time, 23.8% of the women died as a result of breast cancer.
All the women were tested for faulty BRCA genes. Of these, 12% carried one, including 201 women with a mutation in the BRCA1 gene, and 137 with a mutation in the BRCA2 gene.
Survival rates between 2 and 10 years
The study, published in The Lancet Oncology journal, found no difference in overall survival regardless of whether the women had the faulty gene or not. This was true at 2, 5 and 10 years following diagnosis.
After 2 years, survival was 97% for BRCA carriers compared with 96.6% for non-carriers. After 10 years, faulty gene carrier survival was 73.4% compared with 70.1% for non-carriers.
These findings were consistent regardless of whether mutations were in the BRCA1 or BRCA2 gene, the researchers report.