Family genetic counseling can identify children at risk for cancer

As many as 10% of pediatric cancer patients have a cancer-related gene mutation

contributed by Jessica N. Everett, MS, CGC, Cancer Genetics Clinic

As advances in next generation sequencing technology becomes increasingly important in treating adult cancers, the same advances are equally important in managing treatment for pediatric cancer patients. For example, recent work by researchers at the University of Michigan on the Peds-MiOncoSeq study found that identifying mutations present in tumor tissue can lead to changes in treatment recommendations.

But this type of clinical sequencing can also help identify children who have hereditary syndromes that predispose them to cancer risk (Mody et al, JAMA. 2015;314(9):913-925). This study found that 10% of pediatric patients with cancer who had sequencing of their tumor and normal tissue were found to have a gene mutation associated with cancer risk. A second study from the St. Jude-Washington University Pediatric Cancer Genome Project found that 8.5% of their pediatric cancer study population had a gene mutation associated with cancer risk (Zhang et al, NEJM, 2015 Nov 18, 2015 DOI: 10.1056/NEJMoa1508054).

When a child is diagnosed with cancer, the issues and questions that arise can be overwhelming for parents and caregivers. They may be presented with many options for clinical trials and research studies, while also facing multiple medical appointments and juggling school and work responsibilities. The number of specialists involved, questions asked, and amount of new information can be overwhelming.<./p>

Family history and beyond

Identifying patients at risk for hereditary cancer syndromes can provide opportunities to optimize care for the existing cancer, and guide surveillance for cancer survivors who may be at risk for second (or third) malignancies. Identifying patients with hereditary cancer syndromes through family genetic counseling also benefits their family members, who can then engage in cancer prevention strategies to improve outcomes.

Although family history of cancer is often used as a screen for hereditary syndromes, it is important to know that not all pediatric patients with genetic predisposition to cancer will have a family history of related cancers. This can happen for multiple reasons including small family size and young ages of relatives. Nearly half of Peds-MiOncoSeq participants with germline mutations in cancer risk genes and 60% of patients in the St. Jude-Washington University group had no suggestive family history. This emphasizes the importance of collaboration between pediatric oncology and genetics providers in looking beyond the family history to recognize tumor types that suggest genetic risk.<./p>

Family genetic counseling at the U-M

Physicians and genetic counselors in The Cancer Genetics Clinic at the U-M meet with patients and families to review the family history and determine if genetic testing may help to clarify risks for additional cancers in the family. This may allow for targeted screening and risk reduction or prevention in the future. The Cancer Genetics Clinic at the U-M welcomes patients of all ages who may have questions regarding the risk of a genetic predisposition in their family.