PGR and breast carcinoma: Despite the overall higher incidence of breast cancer in European-American (EA) women as compared to African-American (AA) women, AA women are more likely to be diagnosed with breast cancer before age 40 and to have tumors with aggressive pathological characteristics, including high tumor grade, lack of expression of estrogen and progesterone receptors (ER, PR) and HER2 (triple-negative breast cancers), and additional features of basal-like breast cancer (ER−/PR−/HER2−/cy5/6+/EGFR+) [1].