Oestrogen receptors and response to cytotoxic chemotherapy in advanced breast cancer.

Of 54 patients with advanced breast cancer, 21/37 (57%) with oestrogen receptor-positive (ER+) tumours and 11/17 (65%) with oestrogen receptor-negative (ER-) tumours responded to cytotoxic chemotherapy. These data and a survey of the literature indicate that oestrogen receptor status is not a determinant of response to chemotherapy. However, ER+ tumours seem to grow more slowly than ER- ones and the response to chemotherapy tends to be longer in ER+ patients.