The study, led by researchers at Georgetown University Medical Center's Lombardi Comprehensive Cancer Center (LCCC) and published online today in the Journal of Clinical Oncology, is the largest to date that evaluates if genetic testing offered at the time of breast cancer diagnosis affects patients' breast cancer treatment decisions.

In contrast to the 48 percent of women who had double mastectomies after testing positive for a BRCA1 or BRCA 2 mutation, 24 percent of patients with no mutation and four percent of test decliners opted for the more extensive surgery.

"Rapid genetic counseling and testing could serve as a valuable decision-making tool for newly diagnosed breast cancer patients at high risk for carrying a mutation," said Marc Schwartz, Ph.D., associate professor of oncology at Georgetown's LCCC. "Prophylactic mastectomy remains controversial, but this study suggests that for some patients who learn that they are at high risk for developing a second breast cancer, bilateral mastectomy becomes a viable alternative to more traditional breast-conserving therapy or unilateral mastectomy."

A woman who tests positive for the BRCA1/2 mutation has a 40-65 percent risk of contralateral breast cancer meaning breast cancer in the non-cancerous breast. While breast conserving therapy (a combination of lumpectomy plus radiation) and unilateral mastectomy are effective treatments for the newly diagnosed breast cancer, these treatments do not protect against the development of a new breast cancer in the opposite breast.

Although testing was provided free of charge in this study, most insurance companies cover most of the cost for B
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Contact: Elizabeth McDonald
eem6@georgetown.edu
202-687-7707
Georgetown University Medical Center
5-Apr-2004