Correlation between estrogen receptors and response to nonhormonal chemotherapy in metastatic breast cancer

While our data do not show a significant difference in response to cytotoxic chemotherapy between ER-positive and ER-negative patients, they clearly do not confirm the results of Lippman and co-workers, and there is a trend for our data to support those of Kiang and associates. We believe that it is unlikely that estrogen receptor assays will prove to have important predictive value for response to cytotoxic chemotherapy. However, more prospective studies published in detail with a larger number of patients will be needed to resolve this issue.