Results from London Regional Clinical Genetics services over a 5-year period on germline TP53 testing in women diagnosed with breast cancer at <30 years.

BACKGROUND: The most common cancer diagnosed in germline TP53 pathogenic variant (PV) carriers is premenopausal breast cancer. An increased rate of breast tumour HER2 positivity has been reported in this group. Screening for breast/other cancers is recommended in PV carriers. OBJECTIVES: 1. To assess the frequency of germline TP53 PVs reported diagnostically in women with breast cancer at <30 years of age.2. To evaluate the impact of personal/family history and HER2 status on the likelihood of germline TP53 pathogenic/likely pathogenic variant (PV/LPV) identification. METHODS: Genetic test results from patients undergoing diagnostic germline TP53 tests between 2012 and 2017 in the four London Regional Clinical Genetics Services were reviewed. Clinical/pathology data and family history were extracted from genetics files for women diagnosed with breast cancer at <30 years. RESULTS: The overall germline TP53 PV/LPV variant detection rate was 9/270=3.3% in all women diagnosed with breast cancer at <30 years and 2/171=1.2% in those with no second/subsequent cancer diagnosis or family history of TP53-spectrum cancers. Breast cancers were significantly more likely to be HER2-positive in TP53 PV/LPV carriers than in non-carriers (p=0.00006). CONCLUSIONS: Germline TP53 PVs/LPVs are uncommon among women diagnosed with breast cancer aged <30 years without other relevant personal or family cancer history but have an important clinical impact when identified.

Family Communication in Inherited Cardiovascular Conditions in Ireland.

Over 100,000 individuals living in Ireland carry a mutated gene for an inherited cardiac condition (ICC), most of which demonstrate an autosomal dominant pattern of inheritance. First-degree relatives of individuals with these mutations are at a 50 % risk of being a carrier: disclosing genetic information to family members can be complex. This study explored how families living in Ireland communicate genetic information about ICCs and looked at the challenges of communicating information, factors that may affect communication and what influence this had on family relationships. Face to face interviews were conducted with nine participants using an approved topic guide and results analysed using thematic analysis. The participants disclosed that responsibility to future generations, gender, proximity and lack of contact all played a role in family communication. The media was cited as a source of information about genetic information and knowledge of genetic information tended to have a positive effect on families. Results from this study indicate that individuals are willing to inform family members, particularly when there are children and grandchildren at risk, and different strategies are utilised. Furthermore, understanding of genetics is partially regulated not only by their families, but by the way society handles information. Therefore, genetic health professionals should take into account the familial influence on individuals and their decision to attend genetic services, and also that of the media.