OS: Overall survival; b: Regression coefficient; SE: Standard error; HR: Hazard ratio; CI: Confidence interval; pN: Pathological lymph node; ER: Estrogen receptor; NPI: Nottingham prognostic index; trimester of pregnancy at diagnosis£: first vs. second and third; HR£: Unadjusted; HR*: Adjusted for pN, age, tumor, and ER. Here, ESR1 is linked to neoplasm.