ESR1 and breast cancer: As age, estrogen receptor status, progesterone receptor status, Ki-67 count, and the menopause status are important for prognosis with breast cancer, the second model was developed with age, pathological size of the tumor, pathological type, lymphovascular invasion, the number of positive SLNs/number of total SLNs ratio, Her-2 status, estrogen receptor status, progesterone receptor status, Ki-67 count, and the menopause status.