The factors analyzed included palpability, age, augmentation or not, invasive ductal versus invasive lobular carcinoma, invasive versus in situ carcinoma, specimen weight, adjuvant hormonal therapy, margin width, progesterone and estrogen receptors, nuclear grade, luminal A status, human epidermal growth factor receptor 2 (HER2) status, Ki67 ≤19 versus ≥20, and tumor span. This evidence concerns the gene ESR1 and invasive lobular breast carcinoma.