Cancer Genetics Risk Assessment and Counseling (PDQ®): Genetics - Health Professional Information [NCI] - The Option of Genetic Testing
Table 1. Clinical Utility of Genetic/Genomic Testsa continued...
Testing in children
Genetic testing for mutations in cancer susceptibility genes in children is particularly complex. While both parents  and providers  may request or recommend testing for minor children, many experts recommend that unless there is evidence that the test result will influence the medical management of the child or adolescent, genetic testing should be deferred until legal adulthood (age 18 years or older) because of concerns about autonomy, potential discrimination, and possible psychosocial effects.[50,51,52] A number of cancer syndromes include childhood disease risk, such as retinoblastoma, multiple endocrine neoplasia (MEN) types 1 and 2 (MEN1 and MEN2), neurofibromatosis types 1 and 2 (NF1 and NF2), Beckwith–Wiedemann syndrome, Fanconi anemia, FAP, and Von Hippel-Lindau disease (VHL).[53,54] As a consequence, decisions about genetic testing in children are made in the context of a specific gene in which a mutation is suspected. The ASCO statement on genetic testing for cancer susceptibility maintains that the decision to consider offering childhood genetic testing should take into account not only the risk of childhood malignancy but also the evidence associated with risk reduction interventions for that disorder.[1,2] Specifically, ASCO recommends that:
- When screening or preventive strategies during childhood are available (e.g., MEN and FAP), testing should be encouraged on clinical grounds.
- When no risk reduction strategies are available in childhood and the probability of developing a malignancy during childhood is very low (e.g., hereditary breast/ovarian cancer syndrome), testing should not be offered.
- Some patients may be at risk of developing a malignancy during childhood without the availability of validated risk-reduction strategies (e.g., TP53 mutations). The decision to test in such circumstances is particularly controversial.[1,2]
Special considerations are required when genetic counseling and testing for mutations in cancer susceptibility genes are considered in children. The first issue is the age of the child. Young children, especially those younger than 10 years, may not be involved or may have limited involvement in the decision to be tested, and some may not participate in the genetic counseling process. In these cases, the child's parents or other legal surrogate will be involved in the genetic counseling and will ultimately be responsible for making the decision to proceed with testing.[1,2,55] Counseling under these circumstances incorporates a discussion of how test results will be shared with the child when he or she is older.[1,2] Children aged 10 to 17 years may have more involvement in the decision-making process. In a qualitative study of parents and children aged 10 to 17 years assessing decision making for genetic research participation, older, more mature children and families with open communication styles were more likely to have joint decision making. The majority of children in this study felt that they should have the right to make the final decision for genetic research participation, although many would seek input from their parents. While this study is specific to genetic research participation, the findings allude to the importance children aged 10 to 17 years place on personal decision making regarding factors that impact them. Unfortunately cognitive and psychosocial development may not consistently correlate with the age of the child. Therefore, careful assessment of the child's developmental stage may help in the genetic counseling and testing process to facilitate parent and child adaptation to the test results. Another complicating factor includes potential risks for discrimination. (Refer to the Employment and Insurance Discrimination section in the Ethical, Legal, and Social Implications section of this summary for more information.)