PGR and triple-negative breast carcinoma: Specific examples include association of the CHEK2 c.1100delC variant with ER-positive disease [16, 17], and BRCA1, BRCA2, BARD1, BRIP1, PALB2, RAD51C, RAD51D, and TP53 variants with increased risks of triple-negative breast cancer (i.e., tumors that are negative for estrogen receptor [ER], for progesterone receptor [PR], and for amplification of the human epidermal growth factor receptor 2/erythroblastic oncogene B [HER2/ERBB2] gene, TNBC) [18–20].