Hormone receptors in primary and advanced breast cancer.

The use of cytoplasmic ER is an integral part of the management of patients with metastatic breast cancer. Tissue from the primary tumour should be routinely assayed for ER and, when feasible, metastatic tissue should be obtained for assay. In addition, ER is an important prognostic variable for recurrence and overall survival and may be useful in the design of adjuvant therapy trials. Whether knowledge of receptor status correlates with chemotherapy response has yet to be conclusively determined. Whether PgR will ultimately add to the clinical usefulness of ER has also yet to be clearly defined; however, it is known that patients whose tumour contains both receptors have a high response rate to hormone therapy. These questions, and others await confirmation in prospective clinical trials.