We further restricted our analysis to postmenopausal women with ER+ disease, showing that PELP1 tumor levels were positively correlated with E1 concentration in tumor (r = 0.583, P = 0.009, Table 4), E1 and E2 concentration in normal tissue (r = 0.679, P = 0.001; r = 0.618, P = 0.005, respectively) and E1 and E2 plasma concentrations (r = 0.653, P = 0.003; r = 0.519, P = 0.027, respectively). The gene discussed is PELP1; the disease is neoplasm.