Estrogen receptor test
The estrogen receptor test (ERT) is a laboratory test to determine whether cancer cells have
The test uses immunohistochemical techniques on the estrogen receptor (ER). Immunohistochemistry (IHC) methods involve selective identification of antigen proteins by exploiting antigen–antibody relationships.
History
Historically, the ligand binding assay was used to determine ER activity. This method was limited because large quantities of fresh tissue were needed for each assay. IHC can be performed on fixed tissue and needle biopsies,[2] and is more accurate in assessing ER status of a tumor.[3]
Today, ER analysis is one of many routinely performed immunohistochemical assays performed to classify hormone receptor status of breast cancers to provide insight into cancer prognosis and management.
Estrogen receptor types
There are two main types of
Immunohistochemical assessment
The ERT immunohistochemical assessment is a semi-quantitative method used to predict the likelihood of successful treatment of breast cancer with
Various target
In a study in 2002, six breast carcinoma cases were received, characterized, and analyzed through the ERT IHC assessment. The level of known ER activity was classified (negative, low, medium, and high) and selected for observation. After embedment in a paraffin block, the samples were stained using a hematoxylin and eosin staining (H & E staining) system. The IHC analysis was performed on the same day using anti-ER
Estrogen receptor test and breast cancer
Observation of estrogen receptor activity provides insight into growth and proliferation of breast cancer. The complex biochemical reactions of estrogen receptors are necessary for the mediation of cellular interactions in response to various cell-altering factors, including ligands, cofactors, and other simulative complexes.[8]
Monitoring tumor development with the estrogen receptor test
The estrogen receptor is a regulator of cellular functions, including cell growth and proliferation, and can serve as a means of inter-cellular differentiation.[8] Monitoring the activity of the ER via the ERT is necessary as it plays an essential role in normal breast development and function, as well as in cancerous situations. Accurate measurements of the ER activities are critical in the initial classification and monitoring of progression in breast cancers. The ER can serve as an indicative biomarker as it is a potential predictor for the clinical responses of a patient to certain treatments. Patients with breast cancer that is ER-positive at presentation are most likely to respond to cancer treatments through endocrine therapy.[9]
Estrogen receptor test in mammary epithelial cancer
Estrogen receptors are over-expressed in approximately 70% of diagnosed
The ERT has been suggested as a predictor for the level of success of the use of endocrine therapy in cancer treatment. Many of the endocrine therapies for breast cancer treatments involve the use of