Heading Breast Cancer Off at the Pass
Dec. 20, 2000 -- Sometimes choosing a treatment can be the hardest part of receiving a diagnosis. That's certainly true for the more than 180,000 women diagnosed with breast cancer each year. For those whose family history or a genetic defect make them more likely to get the disease, one option is even more daunting: whether to remove one or both breasts to stop the disease before it starts, a mastectomy.
In a follow-up of women who had mastectomies to prevent cancer, Dutch researchers say that doing the surgery before cancer strikes significantly reduces incidence of the disease in those who are at high risk. However, other doctors say not enough solid study has been done to determine how well the surgery lowers breast cancer risk and deaths.
Jan Klijn, MD, of the Erasmus University Department of Clinical Genetics in Rotterdam, The Netherlands, reported the findings last week at a meeting of breast cancer specialists.
According to Klijn, of nearly 70 women who showed no signs of cancer but had defects of either gene known to carry an increased risk of breast cancer -- called BRCA 1 and BRCA 2 genes -- and underwent preventative mastectomy of both breasts, none had developed breast tumors approximately two years later.
The researchers also looked at a comparison group of 70 women about the same age and with the same gene abnormalities but who did not have a mastectomy. Although they were all healthy at the beginning of the study, the comparison group had a higher than usual rate of breast cancer after two years.
Even though the study lasted only two years, statistics lead the researchers to expect that by five years, none of the women who underwent the mastectomies will have developed breast cancer, whereas almost 30% of those who didn't have their breasts removed will develop the illness.
Normal BRCA 1 and BRCA 2 genes make proteins to prevent abnormal cell growth that leads to cancer. But when a defect, or mutation, is present in one of these genes, the possibility increases that a woman will develop breast cancer. According to the American Center Society, a woman who has inherited one of these genetic changes has a 50-60% increased risk for the disease by the time she is 70 years old.