Immunohistochemical assay for detecting estrogen receptors in canine mammary tumors
Graham, J.C.; O'Keefe, D.A.; Gelberg, H.B.
American Journal of Veterinary Research 60(5): 627-630
1999
ISSN/ISBN: 0002-9645 PMID: 10328435 Document Number: 506267
The estrogen receptor (ER) content was measured in 21 canine mammary gland tumors using immunohistochemical examination of formalin-fixed sections. ER were detected in formalin-fixed tissues, using an avidin-biotin alkaline phosphatase immunohistochemical (ICH) assay and were quantified on fresh-frozen tumour samples using a modified dextran-coated charcoal (DCC) assay. Nuclear ER was detected in 7 of 21 tumours using IHC staining, and in 8 tumours using DCC assay. The ER-positive cells in 5 IHC-positive tumours were epithelial cells with histological criteria of early malignancy. The remaining 2 ER-positive tumours detected by use of IHC had ER-positive mast cells within areas of connective tissue around the tumour. It is concluded that immunohistochemistry is an additional method for detection of ER in canine mammary tumors. The main advantage of this type of assay is that it may be performed on formalin-fixed tissues and individual ER-positive cells may be identified.