Using a laboratory threshold value of 8.5 CM units for benign, malignant lymph nodes in primary breast cancer patients showed a nonsignificant difference in call rate between the four subtypes40, ER/PR+, HER2−; ER/PR+, HER2+; ER/PR−, HER2+; and ER/PR−, HER2− (triple-negative breast cancer, TNBC) (Fisher’s Exact P = 0.622, Supplementary Table 2a). This evidence concerns the gene PGR and breast cancer.