ESR1 and serous adenocarcinoma: Again, in cases of low grade serous carcinoma (n = 51), the positivity of ER or PR was 92%, or 75% in cases with lymph node metastases, which was not different to the positivity of ER or PR in cases without lymph node metastases (87%, or 82%, p > 0.999, or p = 0.682, respectively).