Estrogen Receptor/Progesterone Receptor (ER/PR), Immunohistochemical, Paraffin Block

CPT: 88360(x2)
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Test Details


  • ER/PR Assay
  • ER/PR, IHC, Paraffin Block

Test Includes

Estrogen receptor analysis; progesterone receptor analysis


Cancer prognosis: ER and PR positivity is a favorable prognostic factor in breast and endometrial carcinoma and meningioma.

Response to endocrine therapy: Combined ER and PR positivity is associated with increased response to antiestrogen therapies.


In the absence of internal positive control staining, a false-negative result cannot be excluded. The presence or absence of positive internal control staining is indicated on all negative reports. Use of fixatives other than 10% formalin may not yield equivalent or satisfactory results.


Immunohistochemistry (IHC). This is a semiquantitative measurement of ER/PR positive tumor nuclei in stained histologic tissue sections.

Additional Information

Estrogen receptors (ER) are cellular proteins that bind estrogens with a high affinity and specificity. They are a necessary component for estrogen-mediated cellular activity. The presence of progesterone receptors (PR) demonstrates an active ER mechanism for the induction of PR expression. Immunohistochemical staining permits the detection and localization of ER/PR within sections from formalin-fixed, paraffin-embedded tissue.

Clinical utilities for the measurement of ER/PR include patient prognosis and patient response to adjuvant endocrine therapy. Individuals with receptor-positive tumors generally have a better prognosis, as indicated by a longer interval to disease recurrence and a longer overall survival, than patients with receptor-negative tumors. Studies have also shown that the determination of receptor status by immunohistochemistry may be useful in predicting patient response to hormonal therapy.

Specimen Requirements


Formalin-fixed, paraffin-embedded (FFPE) tumor


One paraffin block or seven unstained, positively-charged tissue slides cut at 4 to 5 microns and dried for one hour at 60°C


Paraffin block transport pouch or slide mailer


Specimen should be fixed in 10% neutral-buffered formalin within one hour of collection. Optimum fixation time is six to 72 hours.

Storage Instructions

Maintain specimen at room temperature.

Clinical Information

Special Instructions

Please direct any questions regarding this test to oncology customer service at 800-345-4363.


Harris L, Fritsche H, Mennel R, et al. American Society of Clinical Oncology 2007 update of recommendations for the use of tumor markers in breast cancer. J Clin Oncol. 2007 Nov 20; 25(33):5287-5312. 17954709


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
480277 ER/PR,Immunohistochem,Paraffin 480278 Estrogen Receptor IHC % 14228-1
480277 ER/PR,Immunohistochem,Paraffin 480279 Progesterone Rec. IHC % 14230-7
480277 ER/PR,Immunohistochem,Paraffin 480276 Comment 8251-1
480277 ER/PR,Immunohistochem,Paraffin 480268 Fixative N/A
480277 ER/PR,Immunohistochem,Paraffin 480299 Fixation Time N/A
480277 ER/PR,Immunohistochem,Paraffin 480298 Additional Information 19147-8

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