Scientists at the University of Southampton, UK, recently reported that women who carry a mutation in the BRCA1 or BRCA2 genes are not more likely to die after a breast cancer diagnosis than non-carriers.
The researchers say that in the future this information could help women and their doctors make informed choices about treatment.
"Women diagnosed with early breast cancer who carry a BRCA mutation are often offered double mastectomies soon after their diagnosis or chemotherapy treatment", Eccles noted.
For the study, called POSH (Prospective Outcomes in Sporadic versus Hereditary), the researchers recruited female patients from 127 hospitals in the United Kingdom who were ages 18 to 40 when first diagnosed with invasive breast cancer, excluding those with a previous invasive malignancy.
The patients, 12 percent of whom were found to have faulty genes, were followed up for an average of just over eight years.
"Decisions about timing of additional surgery to reduce future cancer risks should take into account patient prognosis after their first cancer, and their personal preferences".
The medication to target the gene is the first in a fairly new class of medicines for ovarian cancer called PARP inhibitors to also win approval for treating breast cancer.
The safety and efficacy of Lynparza for the treatment of breast cancer was based on a randomized clinical trial of 302 patients with HER2-negative metastatic breast cancer with a germline BRCA mutation. Half had breast-conserving surgery, half had a mastectomy, and fewer than 1% had no breast surgery. Roughly 30 to 60 percent of BRCA1 or BRCA2 carriers will develop breast cancer in their lifetime, compared to an estimated 12 percent of women in the general population.
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.
She said she was now keen to understand how women fared more than 10 years after their diagnosis.
It has been dubbed the "Angelina Jolie gene", after the actress revealed she underwent preventative surgery on learning she had an up to 87% chance of developing breast cancer.
Survival rates after two years were 97 percent for women with a BRCA mutation and 96.6 percent for those without the mutation, the findings showed.
BRCA genes are involved with repairing damaged DNA and normally work to prevent tumor development. "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".
This is of particular note as the majority of breast cancer cases (81%) occur in women over the age of 50.