Test Catalog

Test ID: ESTR    
Estrogen Receptor Immunostain, Technical Component Only

Useful For Suggests clinical disorders or settings where the test may be helpful

Qualitative detection of estrogen receptor alpha protein in a diagnostic setting

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

For the initial technical component only immunohistochemical (IHC) stain performed, the appropriate bill-only test ID will be reflexed and charged (IHTOI). For each additional technical component only IHC stain performed, an additional bill-only test ID will be reflexed and charged (IHTOA).

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Estrogen receptor alpha protein expression is limited to normal and neoplastic tissues related to the reproductive system (breast, cervix, endometrium, uterus, ovary, and prostate).

Interpretation Provides information to assist in interpretation of the test results

This test does not include pathologist interpretation; only technical performance of the stain. If an interpretation is required, order PATHC / Pathology Consultation for a full diagnostic evaluation or second opinion of the case.


The positive and negative controls are verified as showing appropriate immunoreactivity and documentation is retained at Mayo Clinic Rochester. If a control tissue is not included on the slide, a scanned image of the relevant quality control tissue is available upon request, call 855-516-8404.


Interpretation of this test should be performed in the context of the patient's clinical history and other diagnostic tests by a qualified pathologist.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Age of a cut paraffin section can affect immunoreactivity. Stability thresholds vary widely among published literature and are antigen-dependent. Best practice is for paraffin sections to be cut within 6 weeks.

Clinical Reference Recommendations for in-depth reading of a clinical nature

1. Peng Y, Butt YM, Chen B, Zhang X, Tang P: Update on Immunohistochemical Analysis in Breast Lesions. Arch Pathol Lab Med. 2017;141(8):1033-1051. doi: 10.5858/arpa.2016-0482-RA

2. Gibert-Ramos A, Lopez C, Bosch R, et al: Immune response profile of primary tumour, sentinel and non-sentinel axillary lymph nodes related to metastasis in breast cancer: an immunohistochemical point of view. Histochem Cell Biol. 2019;152(3):177-193. doi: 10.1007/s00418-019-01802-7

3. McCullough AE, Dell'orto P, Reinholz MM, et al: Central pathology laboratory review of HER2 and ER in early breast cancer: an ALTTO trial (BIG 2-06/NCCTG N063D [Alliance]) ring study. Breast Cancer Res Treat. 2014;143(3):485-492. doi: 10.1007/s10549-013-2827-0