DNA Testing Should Only Be for Women at Risk

The knowledge of BRCA 1 and 2
gene mutations may lower breast
cancer mortality; © NCI Visuals

Women who are at an increased risk of inheriting the BRCA1 or BRCA 2 gene mutations include those of Ashkenazi (predominantly Eastern European) Jewish descent with a first- or second-degree relative with breast or ovarian cancer. A first-degree relative could be a mother, sister, or daughter; a second-degree relative might be a grandmother or an aunt. Risk factors for women not of Ashkenazi Jewish background include having specific family history patterns, for example, multiple first- or second-degree relatives with breast and/or ovarian cancer. The level of risk for these women is best determined by obtaining a detailed family history and making use of standardized risk assessment tools.

Women who do not have a family history of either breast or ovarian cancer and are unlikely to test positive for the mutations should not be referred for testing, the Task Force emphasised, noting that there are potential harms involved in genetic testing, including false-positive test results.

Testing entails risks. A woman who tests positive for BRCA1 and BRCA2 gene mutations may choose to undergo a procedure such as a preventive mastectomy or oophorectomy which might be unnecessary if a given mutation would not lead to cancer. Women who test positive for genetic mutations may also be vulnerable to job or insurance discrimination.

For those women whose specific family history, counselling and BRCA testing may offer significant benefits: “A woman who gains an understanding of the risk she faces may feel less anxious and have a sense of better control of her future,” said Task Force Chair Ned Calonge, M.D. “If the DNA test result is positive, the patient and her physician should take a shared decision making approach in deciding which preventive measures are appropriate.”

According to the Task Force, women may also choose to undergo intensive screening by frequent clinical breast examinations and mammography or preventive chemotherapy, but the benefits remain uncertain.

MEDICA.de; Source: Agency for Healthcare Research and Quality (AHRQ)