ESR1 and breast cancer: Among postmenopausal women, the difference in WBC counts between patients and controls was greater for patients with ER+/PR+ breast cancer than for those with ER−/PR− breast cancer or ER+/PR− or ER−/PR+ breast cancer, regardless of whether the women were obese (p = 0.002 and p < 0.001, respectively) or non-obese (p = 0.002 and p = 0.009, respectively).