Prevalence of a BRCA2 Pathogenic Variant in Hereditary-Breast-and-Ovarian-Cancer-Syndrome Families with Increased Risk of Pancreatic Cancer in a Restricted Italian Area

Abstract

PVs and LPVs in BRCA1/2 genes are correlated to a high risk of developing breast cancer and/or ovarian cancer (Hereditary Breast and Ovarian Cancer syndrome, HBOC); additionally, in recent years, an increasing number of BRCA 1/2 variants have been identified and associated with pancreatic cancer. Epidemiologic studies have highlighted that inherited factors are involved in 10% to 20% of PCs, mainly through deleterious variants of BRCA2. The frequency of BRCA1/2 germline alterations fluctuates quite a lot among different ethnic groups, and the estimated rate of PVs/LPVs variants in Italian HBOC families is not very accurate, according to different reports. The aim of our study is to describe the prevalence of a BRCA2 PV observed in a selected cohort of HBOC patients and their relatives, whose common origin is the eastern coast of Emilia Romagna, a region of Italy. This study provides insight into the frequency of the variant detected in this area and provides evidence of an increased risk of pancreatic and breast cancer, useful for genetic counseling and surveillance programs.

Keywords: BRCA; HBOC; NGS; cancer; pancreatic cancer; pathogenic variant.

Figure 1

Representative pedigree of a family with BRCA2 c.7561del variant. I–IV represent generations. Circles represent females, squares represent males. Symbols that are fully dark represent breast-cancer patients. Symbols with a quarter represent subjects with other types of cancer. Symbols with a slash indicate deceased individuals. The arrow points to the proband. BC, breast cancer; PC, Pancreatic Cancer; RCC, Renal Cell Carcinoma; BRCA2 +, presence of PV in BRCA2; BRCA2 −, absence of PV in BRCA2.