Oestrogen receptors and breast cancerBMJ 1997; 314 doi: https://doi.org/10.1136/bmj.314.7098.1843 (Published 28 June 1997) Cite this as: BMJ 1997;314:1843
It is time for individualised treatment based on oestrogen receptor status
- Richard M Elledge, Assistant professora,
- C Kent Osborne, Professora
- a Division of Medical Oncology and Radiation Oncology, University of Texas Health Science Center, San Antonio, TX 78284-7884, USA
Breast cancer is marked by great clinical and biological diversity. Some women can be cured, while others die rapidly over just a few months. Systemic treatments can have gratifying and possibly curative effects for some, while for others they add only misery and financial hardship. Given this great heterogeneity, are women with breast cancer best served by therapeutic approaches emphasising homogeneity or ones that reflect the variability of the disease in individual choices of treatment? A case in point is the use of oestrogen receptor status in making decisions about endocrine therapy.
Oestrogen receptors are required for oestrogen stimulated growth and proliferation of breast cancer. They are found to some degree in 50-80% of breast tumours. Endocrine treatments are designed to antagonise the effects of oestrogen. Oophorectomy, luteinising hormone releasing hormone agonists, and aromatase inhibition all reduce the level of oestrogen, while antioestrogens such as tamoxifen competitively block binding of oestrogen to receptors and thus antagonise transcriptional activation of genes required for tumour growth.
Twenty five years ago it was first hypothesised that the response to such endocrine treatments would depend on the presence of oestrogen receptors in the tumours. And indeed, 50-60% of receptor positive metastatic tumours do respond.1 For tumours that test negative for oestrogen and progesterone receptors, the response rate (in terms of tumour …