Women at increased risk for breast cancer because of the genetic BRCA mutations are more likely to think a prophylactic mastectomy is the best way to reduce their risk for the disease, compared to other women who are at high risk, according to researchers at The University of Texas M. D. Anderson Cancer Center.
The study, published in the most recent issue of Cancer
, also finds that the emotional worry was a strong factor leading women - both BRCA mutation carriers and others at high risk for the disease - to opt for the surgery.
It's estimated that .1 to .2 percent of the general population carry either the BRCA 1 or 2 mutation, both of which are associated with an increased risk of breast and/or ovarian cancer. For those with the BRCA1 mutation, their lifetime risk of developing breast cancer is 47-66 percent, with some estimates even higher; those with BRCA2 have a lifetime risk of 40-57 percent.
Women are referred to genetic counseling because of a personal diagnosis of breast cancer at a very young age, or a strong family history of the breast and/or ovarian, explained Jennifer Litton, M.D., assistant professor in M. D. Anderson's Department of Breast Medical Oncology.
"Women who are even suspected to have a BRCA mutation are highly motivated and need to make important decisions regarding their treatment options, even if they don't have cancer," said Litton the study's senior author. "With the study, we wanted to determine the reasons why women make different choices in either screening - including breast-self exams, mammograms, or MRIs - or prophylactic measures, such as medications like Tamoxifen or surgeries."
In conducting the study, the researchers sent surveys to 540 women who received genetic counseling and were screened for the BRCA mutations at M. D. Anderson between 1997 and 2005. Of those surveys, 312 (58 percent) were returned: 217 (70 percent) had breast cancer and 86 (28 percent) tested positive for the BRCA1 or 2 mutation.
In the surveys, patients were asked questions regarding their fear of developing the disease, as well as their feelings on: the screening techniques mammograms and breast-self exams; the drug Tamoxifen and its known side effects, and prophylactic surgeries.
Regarding mammograms and self breast exams, the study found little difference between the BRCA positive and negative cohorts. Neither group felt that mammograms were too difficult to get because of discomfort, nor did either report being too embarrassed to perform breast-self exams. In addition, there was no statistical difference in the two groups' feelings toward Tamoxifen: 37.9 percent of the BRCA positive patients and 46.5 percent of the BRCA negative patients felt that the concerns associated with the drug outweighed its benefits for reducing risk of developing breast cancer.
In evaluating the response to questions regarding prophylactic mastectomies, the researchers began to see significant differences between the two groups, and "worry" as a recurring concern.
When comparing BRCA positive to BRCA negative cohorts: 70 percent versus 40 percent respectively felt that prophylactic mastectomies were the most effective way to reduce their risk of developing the disease; 36.1 percent versus 40.5 percent respectively felt it was too drastic of a measure to prevent breast cancer; 23.9 percent versus 12.5 percent respectively had difficulty in deciding between surgery and screening.
Regarding their degree of worry, 64.7 percent of BRCA positive patients thought a prophylactic mastectomy was the only way to reduce their fear of the disease, compared to 34.4 percent of BRCA negative patients.
When combining both groups, after excluding women with bilateral breast cancer, 81 percent who thought surgery was their best way to reduce their risk, and 84 percent of those who felt that it was their best way to reduce their worry ultimately underwent the procedure. In contrast, 19.1 percent of those who did not feel that the surgery was the best way to reduce their risk and 15.8 percent of women who did not think it was their only way to decrease their worry opted to have a prophylactic mastectomy.
In her clinical experience, Litton has seen many high-risk women, particularly those who test positive for the BRCA 1 or 2 mutation, that initially opt for intensive screening, but after several mammograms, MRIs and biopsies, eventually decide to have a prophylactic mastectomy.
"For clinicians, this study shows that when we're counseling women about prophylactic mastectomies, we need to not just talk about the surgery, but understand their lifestyles," said Litton. "When the worry of developing cancer is interfering with a patient's day-to-day activities, then their quality of life is impacted. These women with a high risk of developing breast cancer may find that despite the surgery and subsequent recuperation, a prophylactic mastectomy improves their quality of life."
Women at highest risk need to ask themselves some very important, personal questions that only they have the answers to, said Litton.
"When making such a personal decision, these women at highest risk need to ask themselves about how they feel about their breast as far as their body image, sexuality, relationship with and support of their partner, as well as their concern for breast cancer. If that worry comes in the way of their day-to-day activities, it should be taken into consideration as part of the patient's decision-making process."
Litton cautioned that the results should not be generalized for the majority of the breast cancer population. Additionally, high risk women, of course, should also be counseled on the risk associated with surgery.
As a follow up to this study, Litton plans to conduct a study with high-risk women of child-bearing age pre- and post-genetic counseling to determine their degree worry, their guilt of possibly passing on the gene to their offspring and thoughts on pre-gestational diagnosis.