ESR1 and breast cancer: Compared with Survivors without recurrence, the primary tumor which developed Early recurrence was significantly associated with a larger tumor size (p = 0.0061), lymph node metastasis (p = 0.037), higher Nottingham Grade (p < 0.0001), higher clinical stage (p < 0.0001), negative ER (p = 0.0085), and negative progesterone receptor (PgR) (p = 0.0023) in TCGA BC cohort (Table 1).