ESR1 and serous adenocarcinoma: There was no difference in the frequency of ER or PR positivity in any of the four subtypes of epithelial ovarian cancer between premenopausal and postmenopausal women, except that the frequncy of PR positivity in serous carcinomas was significantly higher in premenopausal women than in post menopausal women (Table 3, p<0.0001).