ESR1 and invasive ductal breast carcinoma: An interesting finding from our study is the significantly better OS observed in Asian MBC patients compared to the other races of those ≥65 years (P = 0.011), married (P = 0.037), with invasive ductal carcinoma (P < 0.001), with ER+/PR+ disease (P = 0.006), receiving modified radical mastectomy (P = 0.002), undergoing lymph node dissection (P < 0.001), with nodal metastasis (P < 0.001), and with grade 2-3 disease (P = 0.005, P = 0.014).