Usually, the focus of gene mutations BRCA1 and BRCA2 is on increased risk for cancer, so women who test positive with these specific mutations can work toward deterring eventual cancer development. Yet according to a new study, women with these mutations who develop breast or ovarian cancer survive just as long as individuals with these cancers who don’t possess BRCA1 and BRCA2.

How Cancer Genes Work

Mutations of breast or ovarian cancer genes can increase the risk of breast and ovarian cancer because healthy genes are responsible for making proteins that repair cell DNA. When mutated cells can’t repair DNA, they are more likely to become cancerous.

BRCA1 and BRCA2 are passed down through families in both men and women. In men they may increase the risk of male breast cancer and possibly prostate cancer. For all women, the average risk of developing breast cancer is about 13 percent, but having a BRCA1 mutation raises the risk to between 55 and 72 percent. Having the BRCA2 mutation increases the risk to 45 to 69 percent.

Ovarian cancer is less common than breast cancer. It affects just over one percent of women but having the BRCA1 mutation increases the risk to 39 to 44 percent, and the BRCA2 mutation to 11 to 17 percent.

Does BRCA1 and BRCA2 Affect Cancer Survival?

The risk for cancer associated with BRCA1 and BRCA2 is known, but little has been discovered about the effect these genes have on cancer survival. A study out of Stanford University is good news for women with breast or ovarian cancer who have these gene mutations. Although BRCA1 and BRCA2 increase risk, they do not decrease survival; in fact, in some cases, they may increase chances of survival.

Using the Georgia and California Surveillance Epidemiology and End Results (SEEER) database, the records of 22,495 women with breast cancer and 4,320 women with ovarian cancer were analyzed over 41 months. All the women had stages I through IV breast or ovarian cancer, and all were treated with chemotherapy. The study is published in the Journal of the National Cancer Institute.

Breast cancers have receptors that doctors can use to treat cancer, so these receptors were considered along with survival. The receptors are the female hormones estrogen (ER), progesterone (PR), and the protein human epidermal growth factor (HER2). These were the key findings…

  • Women with triple negative breast cancer (no ER, PR or HER2 receptors) who had a BRCA1 or BRCA2 mutation had better survival rates than women without genetic mutations.
  • Women with triple negative breast cancer who had a genetic mutation other than BRCA1 or BRCA2 had the same survival rates as women without any genetic nutation.
  • Women with ovarian cancer who had a BRCA2 mutation or a mutation other than BRCA1 or BRCA2 had better survival rates than women without a genetic mutation.

BRCA1 and BRCA2 Make Chemo More Effective

The researchers suspect that because BRCA1 and BRCA2 mutations make it hard for cells to repair DNA damage, chemotherapies that damage DNA in cancer cells may become more effective. Damaged DNA cannot regenerate. If you have breast cancer and the gene mutations associated with increased risk, be sure to discuss with your doctor chemotherapy options that enhance long-term survival.

For additional help: For more information on BRCA gene mutations, cancer risk, testing and treatment, visit

Source: Study titled “Association of Genetic Testing Results With Mortality Among Women With Breast Cancer or Ovarian Cancer,” by researchers at Stanford University, University of Michigan, et al., published in the Journal of the National Cancer Institute.

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