ESR1 and breast neoplasm: The time to relapse after primary surgery was significantly longer in patients with primary breast tumors with high phosphorylation levels of ER-α Ser167 or with high expression levels of ER-α (1D5), PR (636), PRA, or PRB (P = 0.0076, P = 0.035, P = 0.018, P = 0.0061, and P = 0.023, respectively).