Is It Time for Testing of All 30-Year-Old Women for the Breast Cancer Gene
Dr. Mary Claire King’s search for a breast cancer gene began when she was in graduate school in the late 1960s and continued for more than 20 years -- despite colleagues dismissal that there was no genetic component to cancer. King, today a professor of medicine and genetics at the University of Washington, was undeterred, saying recently that she has gotten used to her colleagues' attitude toward new findings.
“I have developed a sense about this that there are certain people in any field who will spend years saying, ‘I don’t believe it, I don’t believe it, I don’t believe it,’ and then they will without pause move to, ‘I knew it all along, I knew it all along, I knew it all along.’ So you have to treasure that 15 minutes in the gap.”
King’s discovery showed that inherited mutations in the BRCA 1 and BRCA2 genes predispose women to a greatly increased risk of breast and ovarian cancers. Thus far the surgical intervention, in particular risk – reducing salpingo-ooporectomy, reduces risk of both ovarian and breast cancer and reduces overall mortality. Another option, the prophylactic removal of the breasts, also reduces the risk.
However, the fact that many women with mutations in these genes are identified as carriers only after their first cancer diagnosis is unacceptable to the researcher.
“To identify a woman as a carrier only after she develops cancer is a failure of prevention,” King said at the San Antonio Breast Cancer Symposium where she delivered the Distinguished Lectureship in Breast Cancer Research. For this reason King has proposed that all women are screened for the mutations at age 30, regardless of their family history.
“Roughly 50 percent of patients who carry the mutation have no family history of breast cancer,” King said. For those women who are positive for either of the mutations, King said they will be referred to a high-risk clinic where the options include close follow up with mammography or MRI, prophylactic removal of breasts or ovaries, or, potentially, hormone therapy. “You only need to be tested once,” King added, and the vast majority of women will not have a mutation and can go about their life.
Dr. Susan Love, chief visionary officer of the Dr. Susan Love Research Foundation, says it’s premature to say that every woman should be tested at age 30 – or that it would only be once.
“We don’t know about all the genes yet. So you could tell women they don’t have any of the genes we know about. Are you going to go back later and test them again?”
In addition, Love said, the only option for women who have the mutation is to cut off normal body parts, which is excessive. “We need more research,” she added.
Love said that the study on which King based her recommendation was with Ashkenazi Jews in Israel and with a more heterogeneous country such as the United States, the results may not be the same.
In October, King received the 2014 Lasker Special Achievement Award for her contributions to biology and medicine as well as human rights. In addition to discovering the BRCA 1 gene she has also worked with the grandmothers of the Plaza de Mayo of Argentina to help reunite the children who went missing during the military dictatorship of 1975 to 1983.