The relationship between BRCA-associated breast cancer and age factors: an analysis of the Japanese HBOC consortium database

Abstract

BRCA1/2 pathogenic variant prevalence in Japanese breast cancer is unclear. Here, we analyzed BRCA1/2 pathogenic variant prevalence with a particular focus on age factors, using the Japanese HBOC consortium database. All registered subjects were Japanese individuals who underwent BRCA1/2 genetic testing from January 1996 to July 2017 according to the Japanese HBOC consortium database. Cases were extracted and analyzed for each evaluation item. Overall BRCA1 and BRCA2 pathogenic variant prevalence was 11.2% and 9.0% in the cohort of 2366 proband patients, respectively. The age at onset of breast cancer for patients with BRCA1/2 pathogenic variants was significantly lower than that for patients without a BRCA1/2 pathogenic variant. In both BRCA1/2 patients, ages at onset were not statistically significantly different between two subtype groups (ER-positive vs. TNBC). We analyzed the BRCA1/2 pathogenic variant prevalence among age groups in patients with no family history of breast or ovarian cancer. In the TNBC group, the rate of genetic variants was more frequent among younger patients. Our results demonstrated that early breast cancer onset is associated with a BRCA1/2 pathogenic variant in the Japanese population. Younger TNBC patients were more likely to have a BRCA1/2 pathogenic variant irrespective of a family history of breast or ovarian cancer.

The Genetic Analyses of French Canadians of Quebec Facilitate the Characterization of New Cancer Predisposing Genes Implicated in Hereditary Breast and/or Ovarian Cancer Syndrome Families

“…Over the past 20 years, national and international consortia have been developed to increase the pool of both familial and sporadic cancer cases and cancer-free controls suitable for research, a concept that was in part successful in identifying cases suitable for BRCA1 discovery and subsequent validation studies [ 44 , 45 ]. Some examples include The German Consortium for Hereditary Breast and Ovarian Cancer (GC-HBOC), which was established in 1996 (health-atlas.de/projects/2), The Breast Cancer Association Consortium (BCAC) (bcac.ccge.medschl.cam.ac.uk) and The Ovarian Cancer Association Consortium (OCAC), which were established in 2005 (ocac.ccge.medschl.cam.ac.uk), The Japanese HBOC Consortium (JHC) and The Asian BRCA Consortium [ 46 ], which were established in 2012 [ 47 ], and The Latin American Consortium for HBOC (LACAM), which was established in 2019 [ 48 ].…”

Management of patients with BRCA mutation from the point of view of a breast surgeon

“…If diagnosed before 41 years, the risk is 23.9% while for patients between 41 and 49 years the risk is 12.6% [ 11 ]. Women with BRCA1 mutation are more likely to get triple negative (estrogen receptor, progesterone receptor and HER2 receptor not amplified) tumors, and they are more often higher-grade tumors and basal-like subtype [ [12] , [13] , [14] , [15] , [16] , [17] ]. 75% of women with BRCA1 mutation have a triple negative disease, a basal-like phenotype, or both ([ 18 , 19 ]).…”

Is adjuvant chemotherapy necessary in older patients with breast cancer?

“…Women with gBRCAm typically develop breast cancer at an early age. Although this mutation decreases in older people, it is present in a certain population of older patients [22]. Abemaciclib and Olaparib are given orally and are generally well-tolerated [23]; thus, it is acceptable as a treatment for older patients.…”