The gene has come to be known as the "Jolie gene", after the actress Angelina Jolie, who revealed in a New York Times article that she'd had a double mastectomy after testing positive for BRCA 1.
The researchers found that 12 percent of patients had a pathogenic BRCA mutation.
Past studies have suggested 45%-90% of women with the mutation develop breast cancer during their lifetime, compared to roughly 12.5% of women developing breast cancer in their lifetime overall in the UK. The decision marks the first time a drug is indicated specifically for BRCA-mutated breast cancer.
The National Cancer Institute estimates that about 253,000 women will be diagnosed with breast cancer this year and that more than 40,000 will die of the disease.
The researchers say that these findings could give women "more confidence and control" when making decisions about their treatment.
The majority of women (89%) underwent chemotherapy. Dave Fredrickson, Executive Vice President, Head of the Oncology Business Unit, AstraZeneca, recognizes the importance of the news: "This is significant for breast cancer patients, as the identification of BRCA status, in addition to hormone receptor and HER2 status, becomes a potentially critical step in the management of their disease".
Leaky Schiff? Trump Accuses Democratic Lawmaker Of Leaking Details Of Russia Probe
Committee Democrats have also been accused of being behind a leak of inaccurate details of an email sent to Trump Jr. during the presidential campaign.
During the course of the study, out of the 2,733 women, there were 678 deaths, including 651 deaths from breast cancer, 18 from other cancers, and nine from other causes.
"The study found that there was no difference in overall survival two, five or ten years after diagnosis for women with and without a BRCA mutation", a press statement said. "These risks determine treatment, and knowing that BRCA1 or BRCA2 mutations do not result in a different prognosis might change the therapeutic approach for these risks".
The good news for young women who carry the infamous BRCA1 or BRCA2 gene is that their chances of survival after conventional breast cancer treatment are the same as those who don't have the mutation.
But faults in these genes raise the risk of developing breast and ovarian cancers, and a higher proportion of women who are aged under 40 when they are diagnosed have these faulty genes compared to older patients.
Most early-stage breast cancer patients have either a lumpectomy or a mastectomy, and many of them get chemotherapy or radiation afterward to destroy any remaining abnormal cells and reduce the risk of cancer coming back.
Professor Peter Fasching, from Friedrich-Alexander University Erlangen-Nuremberg, Germany, added: "This important topic needs more prospective research as preventive surgical measures might have an effect on what might be a very long life after a diagnosis of breast cancer at a young age".