receptorstatus

Receptor status refers to the presence and level of specific cellular receptors expressed by a tumor, information used to classify cancers and guide therapy. It is determined from tumor tissue samples and can influence prognosis and treatment choices.

In breast cancer, the most clinically important receptors are estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Receptor status is typically assessed with immunohistochemistry (IHC) and, when needed, in situ hybridization (ISH) for HER2. ER and PR are generally considered positive when a defined proportion of tumor cells show nuclear staining; HER2 is scored by membrane staining, with a 3+ score indicating positivity, a 2+ score deemed equivocal and usually followed by FISH or another confirmatory test to assess gene amplification.

Positive ER/PR status suggests potential benefit from endocrine therapies that target hormone signaling, while HER2 positivity indicates eligibility for HER2-targeted therapies such as trastuzumab and related agents. Negative statuses, especially ER-, PR-, and HER2- (often termed triple-negative breast cancer), have different treatment options and generally rely more on chemotherapy and other systemic approaches.

Receptor testing is not limited to breast cancer; many tumors are evaluated for receptors or molecular targets (eg, EGFR, HER2 in other cancers, PD-L1, ALK) to identify targeted therapies or clinical trial opportunities. Receptor status can vary between primary and metastatic sites and may change over time or after treatment, underscoring the importance of re-evaluation in appropriate clinical contexts.