The correlation of ESR1 expression with EERES was moderate to high in breast (r = 0.641, P = 7.038e-128) and endometrial (r = 0.413, P = 2.142e-24) cancer patients but low in ovarian (r = 0.226, P = 8.776e-6) and cervical (r = 0.264, P = 3.182e-6) cancer patients. This evidence concerns the gene ESR1 and cancer.