A Multi-institutional Study of Interlaboratory Variance in the Estrogen and Progesterone Receptor Assays.
- Author:
Ahwon LEE
1
;
Gyungyub GONG
;
Kyeongmee PARK
;
In Ae PARK
;
Woo Hee JUNG
;
Dong Wha LEE
Author Information
- Publication Type:Original Article
- Keywords: Estrogen receptors; Immunohistochemistry; Progesterone receptors; Questionnaire
- MeSH: Antibodies; Breast; Breast Neoplasms; Electronic Mail; Estrogens; Formaldehyde; Handling (Psychology); Immunohistochemistry; Korea; Microwaves; Progesterone; Quality Control; Receptors, Estrogen; Receptors, Progesterone; Surveys and Questionnaires
- From:Journal of Breast Cancer 2010;13(1):46-52
- CountryRepublic of Korea
- Language:Korean
- Abstract: PURPOSE: The expression of hormone receptors is the most reliable factor for predicting the responsiveness to hormonal therapy. At present, immunohistochemistry (IHC) is considered as a practically reliable method. This study was designed to examine the interlaboratory variance in immunohistochemical assays for estrogen receptor (ER) and progesterone receptor (PR) in Korea. METHODS: The Korean Study Group for Breast Pathology (KSGBP) made a questionnaire to know the current situation in HR assay in Korea. The questionnaire was sent to the members of KSGBP by e-mail, which were included eight questions relating to tissue handling, ER/PR IHC procedure and interpretation method. Forty laboratories replied with the completed questionnaire. RESULTS: All 40 laboratories were using formalin as a fixative. Pretreatment was performed using six different methods including autoclave (25%), microwave (30%) and full autostainer (15%). Primary antibodies for ER were SP1 in 40%, 6F11 in 27.5% and 1D5 in 32.5%. Primary antibodies for PR were more variable (seven clones) than those for ER. Interpretation method used was Allred system in 20%, modified Allred system in 15%, report the % of positive tumor cells in 45%, positive/ negative in 15% and others in 5%. The expression rate of ER was ranged from 45.6% to 93% (mean 63.5%) and the expression rate of PR was ranged from 27% to 90% (mean 59.1%). The differences according to the numbers of breast cancer in each institute, primary antibodies, detection systems and interpretation methods did not influence to the expression rate of ER/PR, statistically (p>0.05). CONCLUSION: In Korea, the interlaboratory variance in ER/PR IHC procedure was too huge to make a standardized method. We suggest the proper quality control program such as ER/PR staining with positive internal and external controls and negative control might be better to aim at getting similar results among the different laboratories rather than trying to standardize the procedure.
