RESUMO
Pre-menopausal female patients have a prolonged survival than post-menopausal patients, indicating that estrogen and/or estrogen receptor (ER) may have some biological effects on prognosis. ER expression in cancer tissue has been reported to be a significant prognostic marker in multiple human cancers. However, the prognostic value of estrogen and/or ER on female patients with esophageal squamous cell carcinoma (ESCC) is rarely reported. The present study was undertaken to elucidate the associations of serum estradiol level, tissue estrogen receptor alpha (ERα) and estrogen receptor beta (ERß) expression with clinical response and reproductive factor changes in 387 female ESCC patients. Radioimmunoassay revealed that serum estradiol level was higher in pre-menopausal than those in peri-menopausal and post-menopausal patients. Furthermore, patients with higher serum estradiol level appeared to have a better survival. Immunostaining results suggested that ERα positive (+) expression was mainly located in cytoplasm of tumor cells with a positive rate of 69.9% and ERß (+) was mainly located in nucleus of tumor cells with a positive rate of 64.9%. We did not find the relations of ER expression with tumor invasion (P>0.05), lymph node metastasis (P>0.05), TNM staging (P>0.05) and treatment method (P>0.05). Surprisingly, ERα (+) expression was higher in post-menopausal patients than those in pre-menopausal patients (P<0.05). Patients with number of pregnancy≥4 have a higher ERß (+) expression than those patients with≤3 (P<0.05). Univariate and multivariate survival analysis showed that ERß (+) expression in addition to ERα (-) expression are favorable prognostic markers in female ESCC patients (P<0.05). Further related study is needed to in-depth explore the potential mechanisms of ERα and ERß in survival of female patients with ESCC.