ESR1 and neoplasm: Broeks et al. 6 further investigated this association with respect to tumor estrogen receptor (ER) status, and reported that rs6504950 had stronger association with ER positive (ER+; OR = 0.93; 95% CI 0.90–0.95; P = 7.2 × 10−7)than ER negative disease (ER−; OR = 1.00; 95% CI 0.95–1.05; P = 0.94).