Genetic counseling may influence women's treatment choices, Lombardi study finds

Preliminary results of a research study at Lombardi Cancer Center indicate that newly diagnosed breast cancer patients with a strong family history of this disease are more likely to take more aggressive steps to eradicate their cancer if genetic testing shows they have the inherited form of the disease.

Only a small percentage of women with breast cancer have the inherited form, which means that they have mutations in the BRCA1 and BRCA2 breast-cancer genes (and perhaps other genes which have not yet been identified). Women with a hereditary predisposition to breast cancer run a higher risk of developing not only second breast cancers, but also a higher risk of ovarian cancer. However, for most women, breast cancer is caused not by genetic mutations, but rather by other factors.

The National Cancer Institute-sponsored study was designed to assess whether women thought to have hereditary breast cancer would be interested in free-of-charge genetic testing and counseling, and whether the results of the test would change their minds about how to proceed with treatment. The study involved 175 recently diagnosed women whose breast cancer was suspected of being hereditary.

"Although we are still recruiting for this study and can�t draw any definitive conclusions at this point, we are definitely seeing some interesting trends,� said Claudine Isaacs, MD, associate professor of hematology/oncology. "Our findings so far indicate that newly diagnosed breast-cancer patients at high genetic risk for breast cancer are likely to want genetic counseling and testing, and that the results of this testing have an impact on how women make their decision about whether to have surgery, such as bilateral mastectomy.�

About 70 percent of the eligible women chose to have the testing, Isaacs said, adding that those women were more likely to undergo mastectomies than women who declined the genetic testing altogether. Forty-three percent of the women in whom genetic testing uncovered a hereditary breast-cancer risk opted to have a bilateral mastectomy. Of the women who were tested but received negative or inconclusive results, 24 percent decided to have a bilateral mastectomy, and only 4 percent of the women who declined testing altogether chose the bilateral mastectomy option.

Of the 70 percent who underwent the genetic testing, 21 women had positive results, meaning that they had the genetic mutations indicative of heightened risk for second breast cancer and ovarian cancer. Twelve of these women had been planning to have only a lumpectomy before they received the results of the genetic testing. After getting the positive result, eight proceeded as planned, while four changed their minds and had a bilateral mastectomy instead of the breast-conserving procedure they had originally planned. Three of the 21 had originally planned to have a unilateral mastectomy (only one breast removed)�but after receiving the positive results, all three changed their minds, and one had a lumpectomy while the other two underwent a bilateral mastectomy.

Also collaborating on this research were Marc Schwartz, PhD, assistant professor of cancer control research; and Caryn Lerman, PhD, professor and associate director of cancer control and population science.

The continuing study also will focus on analysis of various subgroups�for example, what factors, if any, predict which women will be interested in pursuing counseling and testing, the impact of genetic counseling and testing on women�s psychosocial well-being, and whether the extent of family history in women with uninformative or negative test results influences the choices they make.

Georgetown University Medical Center includes a biomedical research enterprise, and the nationally ranked School of Medicine and School of Nursing and Health Studies. Lombardi Cancer Center, an integral component of Georgetown University Medical Center, is one of only 38 Comprehensive Cancer Centers in the United States�and the only one in the Washington, D.C. area�designated by the National Cancer Institute.