Pathogenic variants in BRCA2 [odds ratio (OR) = 13.9; p = 1.92 × 10<sup>-16</sup>], CHEK2 (OR = 3.7; p = 6.24 × 10<sup>-24</sup>), and PALB2 (OR = 6.6, p = 0.01) were associated with significantly increased risks of MBC.
Here, we investigated the contribution of BRCA1, BRCA2 and CHEK2 alterations to MBC predisposition in Italy by analysing a large series of MBC cases, unselected for breast cancer family history and all negative for BRCA1/BRCA2 germ-line mutations.
To extend our knowledge on the role of CHEK2 in susceptibility to male breast cancer we have screened a series of 26 breast cancer cases with male representation for germline sequence variation in the CHEK2 gene.
We wanted to evaluate the significance of CHEK21100delC in predisposition to MBC by assessing its frequency in a population-based material of 114 Finnish MBC patients.
By multivariate logistic regression models, we found a significant increased MBC risk for 3 SNPs, in particular, with codominant models, for rs2046210/ESR1 (OR = 1.71; 95 % CI: 1.43-2.05; p = 0.0001), rs3803662/TOX3 (OR = 1.59; 95 % CI: 1.32-1.92; p = 0.0001), and rs2981582/FGFR2 (OR = 1.26; 95 % CI: 1.05-1.50; p = 0.013).
Comparing the ORs for male breast cancer with the published ORs for female breast cancer, three SNPs--rs13387042 (2q35), rs3803662 (TOX3), and rs6504950 (COX11)--showed significant differences in ORs (p<0.05) between sexes.
Male BC is almost exclusively hormone receptor positive (+), including the androgen receptor (AR), and is associated with an increased prevalence of BRCA2 germline mutations, especially in men with increased risk for developing high-risk BC.
In terms of hormone receptors, 80.5% (62/77) of patients with MBC were estrogen receptor positive, 75.3% (58/77) of patients were progesterone receptor positive, and only 6.5% (5/77) of patients were HER2 overexpressing.
The aim of this study was to explore the characteristics and prognostic information of estrogen receptor-positive/progesterone receptor-negative (ER+/PR-) male breast cancer.
In order to investigate whether epigenetic signatures could define molecular subgroups of MBCs, we performed promoter methylation analysis of genes involved in signal transduction and hormone signalling in <i>BRCA1/2</i> mutation-positive and -negative MBCs.
Body mass index (P = .023) and DACH1 (P = .034) were correlated with MBC prognosis, whereas the expression of AR (P = .049), SIX1 (P = .048), surgery (P < .001), and chemotherapy (P = .001) were important for FBC in addition to already known factors: tumor size and location, TNM stage (lymph nodes and organ metastasis), radiotherapy, and ER and human epidermalgrowth factor receptor-2 (HER2) expression.