Disclosures: Jigisha P. Thakkar: None; Divyesh G. The content of this article has been reviewed by independent peer reviewers to ensure that it is balanced, objective, and free from commercial bias.
There is nowadays emerging interest in understanding the interplay between the different members of the nuclear hormone receptor family and their role in tumor growth. They are ligand-activated transcription factors that can also act through ligand-independent mechanisms. Receptors other than the classical nuclear steroid receptor family are also involved in generating progesterone P4 -mediated effects reviewed in Mueck et al.
Metrics details. Estrogen receptor ER and progesterone receptor PR testing are performed in the evaluation of breast cancer. While the clinical utility of ER as a predictive biomarker to identify patients likely to benefit from hormonal therapy is well-established, the added value of PR is less well-defined.
The ovarian steroid hormones, estradiol and progesterone, and their nuclear receptors estrogen receptor [ER] and progesterone receptor [PR]are involved in breast cancer development. However, serious consideration of PR isoforms as important drivers of early breast cancer progression and ER modulators is timely and significant. Indeed, progress has been hindered by ER-centric experimental approaches.
Breast cancer cells taken out during a biopsy or surgery will be tested to see if they have certain proteins that are estrogen or progesterone receptors. When the hormones estrogen and progesterone attach to these receptors, they fuel the cancer growth. Cancers are called hormone receptor-positive or hormone receptor-negative based on whether or not they have these receptors proteins.
Estrogen receptor-positive ER-positive breast cancer is the most common type of breast cancer diagnosed today. According to the American Cancer Societyabout 2 out of every 3 cases of breast cancer are hormone receptor-positive. Most of these cases are ER-positive, meaning that there are estrogen receptors on the surface of the cell that bind to estrogen.
Approximately one-third of breast cancer patients develop recurrent tumors and subsequently succumb to the disease. The treatment strategy for recurrent breast cancer is generally determined based on information from the pathological diagnosis of the primary lesion. However, tumor phenotype, as represented by estrogen receptor ERprogesterone receptor PR and human epidermal growth factor 2 HER2 status occasionally changes at recurrence 1 — 4.
Skip to Content. To help doctors give their patients the best possible care, the American Society of Clinical Oncology ASCO and the College of American Pathologists CAP developed evidence-based recommendations to improve the accuracy of testing for estrogen and progesterone receptors for breast cancer. Cancer cells with these receptors depend on estrogen and related hormones, such as progesterone, to grow.
Hormone receptor tests are both prognostic and predictive. Hormone receptors also provide information about treatment options. Hormone therapies slow or stop cancer's growth by changing the hormonal milieu.