The study “Impact of oophorectomy on cancer incidence and mortality in women with a BRCA1 or BRCA2 mutation” that was recently published in the Journal of Clinical Oncology (Finch AP, et al. 2014 February 24 [Epub ahead of print]) provides an update of previous work by the same investigators on a similar population.
For several years now we have known that removing the ovaries and the fallopian tubes (prophylactic bilateral salpingo-oophorectomy [BSO]) substantially reduces a woman’s risk for developing ovarian or fallopian cancers, as well as for breast cancer, if the surgery is done before menopause. Earlier studies (including several by the authors of the current study) have proved that BSO saves lives among high-risk women, particularly those with an inherited mutation in the BRCA1 or BRCA2 (BRCA1/2) cancer susceptibility genes. This study, therefore, builds on a robust body of existing work.
The novel aspects of this study are the size of the benefit from BSO, and the age-specific ovarian cancer risk estimates for BRCA1/2 mutation carriers. The 77% to 80% estimated improvement in survival as a result of BSO is dramatic, and larger than reported in previous studies. The investigators also estimate that a BRCA1 mutation carrier has approximately a 4% probability of developing ovarian cancer between ages 35 and 40 years, and approximately a 14% probability of developing ovarian cancer between ages 35 and 50 years.
For BRCA2 mutation carriers, these risks are smaller and occur later. The authors conclude that for BRCA1 mutation carriers, BSO should be performed at age 35 years rather than waiting until age 40 years.
How should patients and their physicians interpret this new information? Rather than representing a substantial change in our knowledge, this study confirms and expands on what we already know—that high-risk women with BRCA1/2 mutations should undergo BSO by age 40 years, and that BRCA1 mutation carriers may wish to consider earlier BSO, depending on their childbearing plans, family history, and other health issues.
For each woman, the decision to undergo prophylactic surgery for cancer risk reduction is very personal. We recommend that women who may have a high inherited risk of breast and/or ovarian cancer seek expert advice from a cancer-genetics professional.
Resources The Stanford Women’s Cancer Center offers this service by way of the Stanford Women’s Cancer Genetics Clinic (appointments can be scheduled by calling 650-498-6004; further information is available at http://cancer.stanford.edu/cancergenetics/). Additional resources include the National Comprehensive Cancer Network (www.nccn.org), which provides evidence-based practice guidelines for the care of patients with BRCA1/2 mutations; FORCE (www.facingourrisk.org), an online support group for BRCA1/2 mutation carriers; and an online decision tool developed by Stanford investigators (http://brca tool.stanford.edu), which allows women with BRCA1/2 mutations to compare different options for managing their cancer-related risks.
