Researchers from the M. D. Anderson Cancer Center have reported that women who carry a BRCA mutation are more likely to believe that prophylactic mastectomy is the best way to reduce their risk and worry of breast cancer compared with other high-risk women. The details of this study appeared in the April 15, 2009 issue of Cancer.[1]

Inherited mutations in two genes—BRCA1 and BRCA2—have been found to greatly increase the lifetime risk of developing breast and ovarian cancer. Mutations in these genes can be passed down through either the mother’s or the father’s side of the family. Women with a BRCA1 mutation have a 47-66% lifetime risk of developing breast cancer, and women with a BRCA2 mutation have a 40-57% lifetime risk of developing the disease. These statistics are compared with a 13% lifetime risk of breast cancer in the general population.

Researchers conducted a study that surveyed 312 women who received genetic counseling and were screened for BRCA mutations at the M. D. Anderson Cancer Center between 1997 and 2005. Of those surveyed, 70% (217 women) had breast cancer and 28% (86 women) tested positive for a BRCA mutation.

The survey included questions regarding the fear of developing the disease as well as feelings regarding screening techniques (mammogram and breast self-exam) and prophylactic strategies (tamoxifen [Nolvadex®] and prophylactic mastectomy). The researchers compared the responses of women who were BRCA positive and those who were BRCA negative.

Among BRCA positive women, 70% felt that prophylactic mastectomy was the most effective way to reduce their risk of breast cancer compared with 40% of BRCA-negative women. Furthermore, 64.7% of BRCA-positive women felt that prophylactic mastectomy was the only way to reduce their worry regarding the disease compared with 34.4% of BRCA-negative women.

There were no significant differences between the two groups regarding feelings about mammograms, breast self-exams, or tamoxifen; however, feelings about prophylactic surgery appeared to be drastically different and appeared to be driven primarily by worry among BRCA-positive women. Of the women who felt that prophylactic mastectomy was the best way to reduce their risk, 81% underwent the surgery (compared with 19.1% of those who disagreed); and of the women who felt that the surgery was the only way to reduce their worry, 84.2% proceeded with surgery (compared with 15.8% of those who disagreed).

The researchers concluded: “BRCA mutation carriers were more likely to believe prophylactic mastectomy to be the best way to reduce both risk and worry of breast cancer. High-risk women who agreed that prophylactic mastectomy was more likely to reduce risk and worry of breast cancer were more likely to proceed with this intervention.”

Comments: It is possible that women with BRCA mutations choose prophylactic mastectomy over the rigorous screening that would be necessary to detect and treat early breast cancers. Thus, mastectomy would reduce anxiety in this population.

Reference:

[1] Litton JK, Westin SN, Ready K, et al. Perception of screening and risk reduction surgeries in patients tested for a BRCA deleterious mutation. Cancer. 2009; 115: 1598-1604.