Estrogen receptors and responsiveness of advanced breast cancer to chemotherapy.

We reviewed 89 patients with disseminated breast cancer who had at least one valid estrogen receptor (ER) assay and who underwent one or several trials of chemotherapy. The responses were assessed by two independent extramural reviewers. Of the 89 patients, 81 were evaluable; 28 of 36 (77.8) ER-positive (ER+) and 28 of 45 (60.7%) ER-negative (ER-) tumors reached at least one remission. Of patients who had received Adriamycin-containing therapy, 13/20 (65%) ER+ and 12/34 (35.3%) ER-tumors experienced a remission . ER+ breast cancer tends to respond better to Adriamycin-containing combinations than ER-negative tumors. This study does not support the thesis that lack of estrogen receptor in breast cancer predicts favorable for response to chemotherapy.