Comparison of estrogen receptor determinations by a biochemical ligand-binding assay and immunohistochemical staining with monoclonal antibody ER1D5 in females with lymph node positive breast carcinoma entered on two prospective clinical trials
✍ Scribed by Steven R. Alberts; James N. Ingle; Patrick R. Roche; Stephen S. Cha; Lester E. Wold; Gist H. Farr Jr.; James E. Krook; H. Sam Wieand
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 830 KB
- Volume
- 78
- Category
- Article
- ISSN
- 0008-543X
No coin nor oath required. For personal study only.
✦ Synopsis
BACKGROUND.
The measurement of estrogen receptors (ER) in breast cancer specimens has traditionally been assessed with a tlextran-coated charcoal assay (DCCA).
More recently the immunohistochemical staining (IHC) method has gained increasing popularity because of its ability to use fixed tissue, assess needle biopsies, and reduce cost. Controversy exists over the accuracy of IHC compared with that of DCCA in determining ER. We compared these two techniques using tumor tissue obtained from a large group of females with lymph node positive breast carcinoma with long term follow-up.
METHODS.
Breast carcinoma tissue was obtained from a large group of females with node positive breast carcinoma participating in two adjuvant chemotherapy trials. ER was determined by the traditional DCCA method and by IHC using the ERlD5 antibody. Disease free survival (DFS) and overall survival (0s) were assessed by each of these methods.
RESULTS.
ER status was determined by DCCA and IHC in tumor tissue obtained from 316 females. A concordance of 79% was observed for the determination of ER-positive tumors. Of the discordant results, the majority of DCCA-negative, IHCpositive tumors could be explained by a low level of DCCA positivity ( < l o fmol) or IHC staining of nonmalignant cells. A much higher rate of discordant results was observed in premenopausal females. Of the DCCA-negative, IHC-positive patients 97% were premenopausal and of the DCCA-positive, IHC-negative patients 79% were premenalpausal. ER by DCC appears to perform better than ER by IHC as a prognostic factor in terms of DFS and (IS. CONCLUSIONS. When compared with DCCA, IHC with monoclonal antibody ERlD5 appears to be a reajonable substitute for the determination of ER. Although