genetic testing after cancer diagnosis

Following a diagnosis of breast cancer, some younger women may be concerned about the risk of breast cancer developing in their close family members, such as their mother, sisters or daughters. It is important for these women to discuss their concerns with a health professional, who may recommend referral to a specialist family cancer clinic if appropriate.

Family cancer clinics provide a service for people with a family history of cancer and their health professionals and can give an estimate of the likelihood of a woman carrying an inherited mutation in a cancer predisposing gene. Although it is now technically possible to test for mutations in some cancer predisposing genes, genetic testing is an appropriate option for only a small proportion of individuals, usually those with a strong family history of breast and/or ovarian cancer.

Genetic testing is offered only with pre- and post-test counselling to discuss the limitations of testing, plus the advantages and disadvantages of being tested, both for the woman and her family. Should a mutation be found, predictive genetic testing may be offered to unaffected adult family members (both male and female) who may also be at risk of carrying the same mutation. Women who test positive for a mutation in BRCA1 or BRCA2 are also at increased risk of developing a second primary breast cancer or ovarian cancer, and should be referred to a cancer specialist for discussion about management options.