Of those diagnosed with breast cancer, 15–20% are classified as triple-negative breast cancer (TNBC) [2], which is identified by the absence of an estrogen receptor (ER) and a progesterone receptor (PR) and does not make too much of epidermal growth factor receptor type 2 (Erbb2/HER2) [3]. This evidence concerns the gene PGR and triple-negative breast carcinoma.