Progress Seen on Test for Women at Risk of Hereditary Breast Cancer

Researchers reports that they are close to developing a simple, fast, and inexpensive means of identifying women with breast cancer who are at the greatest risk of carrying a damaged version of BRCA1 or BRCA2, genes predisposing them to hereditary forms of the disease.

These genes put women at a much greater risk of developing cancers in the same or other breast, as well as ovarian cancer, according to researchers at Jefferson Medical College and the Kimmel Cancer Center of Thomas Jefferson University in Philadelphia.

Currently, women with a family history of breast or ovarian cancer must undergo genetic sequencing to see if they carry damaged versions of BRCA1 or BRCA2, which may raise the risk of cancer as much as 80 percent over their lifetime. The testing takes several weeks and is usually very expensive.

"This is important because patients with breast cancer who have mutations in BRCA1 or BRCA2 may be better candidates for certain types of therapy," said Dr. Bruce C. Turner, assistant professor of radiation oncology at Jefferson.

"For example, they may be better candidates for mastectomy than lumpectomy and radiation therapy -- also known as breast-conserving therapy. Those patients electing breast conserving therapy need to have constant monitoring not only of their treated breast but also their other breast if they don't have a mastectomy on that side, and also of their ovaries," he said.

Researchers have developed the test, with assistance from Coulter Pharmaceuticals in San Diego, using a special protein called a monoclonal antibody to determine if BRCA1 is damaged. The antibody acts as a "guided missile" aimed directly at the protein made by BRCA1.

If the antibody doesn't find the normal protein, it suggests that the gene is damaged or missing, and sequencing needs to be done to find the exact mutation that is causing the cancer, according to the study presented to the American Society of Clinical Oncology at their annual meeting in San Francisco.

Researchers stained samples of breast cancer cells obtained during breast biopsy with a specially designed antibody to BRCA1. A breast cancer carrying an altered BRCA1 gene will be negative for the staining because the alternation would prevent the gene from making its protein, said Turner.

Other sources: Thomas Jefferson University