For most women, the odds of getting ovarian cancer is pretty slim. According to the National Cancer Institute, only 1.4 out of every 100 women in the United States will face an ovarian cancer diagnosis in her lifetime. The odds rise dramatically, however, for women who carry an inherited gene mutation known as BRCA1. For these women, the odds of getting ovarian cancer is 39 for every 100 BRCA+ women. Traditional treatments often save lives once disease develops but preventive ovary removal surgery (oophorectomy) by age 35 is the best defense, according to a new study.
The BRCA1 and BRCA2 gene mutations both increase the risk of breast and ovarian cancers. When these cancers run in families, one or the other gene mutation is usually present. Genetic testing reveals the mutation.
The actress, Angelina Jolie, brought the subject of preventive surgery to the spotlight when she chose to undergo a double mastectomy in 2013 to reduce her risk of breast cancer, which killed her 56-year-old mother. The surgery reduced Jolie's risk of breast cancer from 87% to 5%.
The same protection comes with the removal of the ovaries and fallopian tubes to prevent ovarian cancer, according to a study involving women from Austria, Canada, France, Italy, Norway, Poland, and the US who were identified on an international registry as having tested positive for the BRCA mutation. When asked to participate, 5,787 of them completed questionnaires describing their history of motherhood, hormone use, and surgeries, including preventive mastectomy and oophorectomy. Of these women:
- 2,274 had ovaries intact
- 2,123 had ovaries removed before the study started
- 1,390 had ovaries removed during the course of study
Each woman was followed for an average of 5.6 years after enrolling in the study, which ran from 1995 through 2011. The objective was to determine how preventive oophorectomy affects the overall rate of death by age 70.
During the course of the study:
- 511 women died:
- 333 from breast cancer
- 68 from cancer of the ovary, fallopian tube, or peritoneum
- 110 from other causes
- 186 developed ovarian, fallopian tube, or peritoneal cancer during the study
Furthermore, the research revealed that when preventive oophorectomy took place at age 35 or sooner (if a younger woman wanted no more children), she experienced an average of:
- 77% reduced risk of death from any cause
- 80% reduced risk of ovarian cancer
When preventive oophorectomy was delayed, there was a:
- 4% increased risk of ovarian cancer if oophorectomy occurred at age 40
- 14.2% increased risk if performed at age 50
Dr. Steven Narod, a lead researcher affiliated with the Women's College Hospital in Canada, says the benefits of preventive ovary removal increases a woman's chance of living until age 70 more than chemotherapy does after cancer is diagnosed. He adds the benefits are just as effective for both the BRCA1 and BRCA2 mutations.
Source: Narod, Steven A, et al. "Impact of Oophorectomy on Cancer Incidence and Mortality in Women With a BRCA2 or BRCA2 Mutation." Journal of Clinical Oncology. American Society of Clinical Oncology. Feb 24, 2014. Web. Mar 30, 2014.