Hormone receptors: their role in predicting prognosis and response to endocrine therapy.

This review highlights some of the recent advances in the use of steroid receptors for management of breast cancer patients and pinpoints needs for future clinical trials. Estrogen receptor (ER) assays are now being used to predict responsiveness to endocrine therapy in patients with advanced disease; hence attempts are now underway to determine their usefulness in deciding whether or not to include endocrine therapy in an adjuvant regimen. As an effort preliminary to an actual adjuvant trial 145 patients with operable breast cancer and an ER assay were examined for recurrence and survival. The data show that irrespective of age nodal status size of tumor or location of tumor patients with ER- tumors recurred earlier than those with ER+. Also survival was adversely affected in patients with ER- tumors supporting the notion that ERtumors are more aggressive in their growth behavior. Consequently though not unequivically patients with ER- tumors respond with a much higher objective rate to chemotherapy than ER+ subjects; this notion is based on the assumption that tumor aggressiveness and responsiveness to chemotherapy are determined primarily by ER status rather than menopausal status but this assumption is unproven until a placebo trial is carried out. In premenopausal patients a combination of ovariectomy plus either antiestrogen or aminoglutethimide and hydrocortisone is preferred over combination chemotherapy; in postmenopausal patients either antiestrogens or aminoglutethimide and hydrocortisone would be effective. Progesterone receptor (PR) and its correlation to tumor status is now under investigation. Early results show that a response rate of 14% occurred in ER- PR- subjects; and the presence of both receptors is associated with the highest response rate.