Abstract 166P
Background
Hereditary breast (BC), ovarian (OC) and pancreatic (PC) cancers are the major BRCA-associated tumours. However, some BRCA1/2-non informative patients with a strong cancer personal and/or family history need a further genetic testing through a multi-gene panel including other high- and moderate-risk susceptibility genes. In recent years, Next-Generation Sequencing has allowed to study multiple genes simultaneously, reducing analysis costs, increasing genetic data, and offering more information to patients.
Methods
Our study was aimed to evaluate if some BC, OC and PC patients should be offered multi-gene panel testing, based on well-defined criteria regarding their cancer personal and/or family history, such as early onset of cancer, occurrence of multiple tumours, and presence of two or more affected first-degree relatives. For this reason, 205 out of 915 BC, OC and PC patients, resulted BRCA1/2 non-informative and with significant cancer personal and/or family history, were genetically tested for germline pathogenic or likely pathogenic variants (PVs/LPVs) in genes different from BRCA1/2
Results
Our study revealed that 31 (15.1%) out of 205 patients harboured germline PVs/LPVs in no-BRCA genes, including PALB2, CHEK2, ATM, MUTYH, MSH2, RAD51C. In particular, we found that 11 out of 24 (45.8%) BC patients harbouring PVs/LPVs in no-BRCA genes showed a bilateral breast cancer. Interestingly, in the absence of multi-gene panel analysis, a considerable fraction (15.1%) of PVs/LPVs would have been lost in this setting of patients.
Conclusions
Providing a multi-gene panel testing to BRCA1/2-non informative BC, OC and PC patients with a strong cancer personal and/or family history could significantly increase the detection rates of germline PVs/LPVs in other cancer predisposition genes beyond BRCA1/2. The use of a multi-gene panel testing could improve the inherited cancer risk estimation and clinical management of patients and unaffected family members.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
University-Hospital Policlinico \"Paolo Giaccone\", Palermo, Italy.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.