The effect of chemotherapy on status of estrogen receptors in primary tumors and lymph node metastases of human ductal breast cancer

The aim of the study was the evaluation of ERalpha and ERbeta expression in primary tumors and lymph node metastases of breast cancer as well as the assessment of the influence of preoperative chemotherapy on these receptors with regard to changes in morphological appearance of primary tumors and their metastases. Immunohistochemical examinations were conducted on surgically removed ductal invasive breast cancers and their lymph node metastases of 135 patients. Seventy-one patients were spared preoperative chemotherapy which was administered to other 64 patients. Primary breast cancers with preoperative chemotherapy showed lower mean percentage of cells with a positive reaction to ERalpha and ERbeta as compared to primary tumors without preoperative chemotherapy. There were positive correlations among primary tumors and lymph node metastases regardless of preoperative chemotherapy applied. On the other hand, ERalpha and ERbeta expressions were negatively correlated in primary tumors without chemotherapy in contrast to primary tumors after chemotherapy. Furthermore, it was observed that preoperative chemotherapy was responsible for significantly less damage to lymph node metastases of breast cancer in comparison to primary tumors. In cases of such advanced damage of primary tumors that made determination of estrogen receptor expression impossible, their evaluation was performed on metastases to regional lymph nodes. Although preoperative chemotherapy did not severely impair estrogen receptor expression, presented changes of their distribution are a sufficient reason for simultaneous labeling of estrogen receptors in both primary tumors and metastases due to various sensitivity to chemotherapy of primary cancers in comparison with involved lymph nodes.