Women with BRCA gene mutations are at increased risk for breast and ovarian cancers. These findings suggest ways that women with these inherited mutations can reduce their ovarian cancer risk without having their ovaries surgically removed, the University of Pennsylvania researchers said.
"Patients deserve better cancer-risk reduction options than surgically removing their healthy breasts and ovaries," review co-author Dr. Susan Domchek, executive director of the Basser Research Center for BRCA at Penn Medicine's Abramson Cancer Center, said in a university news release.
Domchek and her colleagues reviewed 44 studies and found that breast-feeding and tubal ligation were associated with lower rates of ovarian cancer in women with a BRCA1 mutation, while the use of birth control pills was associated with a reduced risk of ovarian cancer in women with BRCA1 or BRCA2 mutations.
The researchers also identified factors that may increase the risk of cancer in women with BRCA mutations. For example, smoking may heighten the risk of breast cancer in women with a BRCA 2 mutation.
The findings are to be published in the June issue of the Journal of the National Cancer Institute.
"Our analysis reveals that heredity is not destiny, and that working with their physicians and counselors, women with BRCA mutations can take proactive steps that may reduce their risk of being diagnosed with ovarian cancer," lead author Timothy Rebbeck, professor of epidemiology and cancer epidemiology and risk reduction program leader at the Abramson Cancer Center, said in the news release.
"The results of the analysis show that there is already sufficient information indicating how some variables might affect the risk of cancer for these patients," he added.
About 39 percent of women with a harmful BRCA1 mutation and up to 17 percent of those with a harmful BRCA2 mutation will develop ovarian cancer by age 70, compared with 1.4 percent of women in the general population.
Between 55 percent and 65 percent of women with a harmful BRCA1 mutation and 45 percent of women with a harmful BRCA2 mutation will develop breast cancer by age 70, compared with about 12 percent of women in the general population.
Both BRCA mutations have also been linked with increased risk for several other types of cancer, according to the researchers.
"It's imperative that we continue examining and building upon past research in this area so that we can provide BRCA mutation carriers with options at every age, and at every stage of their lives," Domchek noted.
The U.S. National Library of Medicine has more about ovarian cancer.