Revisiting the Implications of Positive Germline Testing Results Using Multi-gene Panels in Breast Cancer Patients
Georgios Tsaousis, Eirini Papadopoulou, Κωνσταντίνος Αγιαννιτόπουλος, Georgia Pepe, Νικόλαος Τσούλος, Ioannis Boukovinas, Theofanis Floros, R. Iosifidou, Ourania Katopodi, Anna Koumarianou, Christos Markopoulos, Konstantinos Papazisis, Vasileios Venizelos, Achilleas Kapsimalis, Grigorios Xepapadakis, Amanda Psyrri, Eugéniu Banu, Dan Eniu, Alexandru Blidaru, Dana Lucia Stănculeanu, Andrei Ungureanu, Vahit Özmen, Sualp Tansan, Mehmet Tekinel, Şuayib Yalçın, George Nasioulas
Abstract
BACKGROUND/AIM: The use of multi-gene panels for germline testing in breast cancer enables the estimation of cancer risk and guides risk-reducing management options. The aim of this study was to present data that demonstrate the different levels of actionability for multi-gene panels used in genetic testing of breast cancer patients and their family members. MATERIALS AND METHODS: We performed an analysis in our clinical database to identify breast cancer patients undergoing genetic testing. We reviewed positive results in respect of risk estimation and management, cascade family testing, secondary findings and information for treatment decision-making. RESULTS: A total of 415 positive test reports were identified with 57.1%, 18.1%, 10.8% and 13.5% of individuals having pathogenic/likely pathogenic variants in high, moderate, low and with insufficient evidence for breast cancer risk genes, respectively. Six point seven percent of individuals were double heterozygotes. CONCLUSION: Germline findings in 92% of individuals are linked to evidence-based treatment information and risk estimates for predisposition to breast and/or other cancer types. The use of germline findings for treatment decision making expands the indication of genetic testing to include individuals that could benefit from targeted treatments.