Once an individual has had genetic testing for inherited cancer predisposition this information could help their close family members. For example, when a BRCA mutation or a mutation in another inherited cancer gene is found, it is important for close family members (with or without a diagnosis of cancer) to know so they too can be proactive with cancer risk management and prevention options if they are identified to also have the familial mutation. It is usually up to the first individual in the family identified with a mutation to share their positive genetic test result with their relatives. Unfortunately, prior US-based studies suggest low rates of testing among at-risk family members1 the reasons for which are unclear, although higher rates of testing among family members were reported in a study conducted in Spain.2
It is also important for individuals who are the first person in their family to have genetic testing for inherited cancer and receive a negative result to share their results with family members. This may help to prevent unnecessary testing in the family and/or clarify the meaning of their negative result.
Tools exist to help facilitate sharing of positive test results among family members. These tools include creating a ‘family sharing letter’ to briefly describe the mutation that was found, what it means, and where relatives can access more information.
1Barsevick AM et al. J Fam Psychol. 2008 Apr;22(2):303-12. PMID: 18410217.
2Sanz J et al. Fam Cancer. 2010 Sep;9(3):297-304. PMID: 20091130.