IMMUNOCYTOCHEMICAL ASSAY FOR ANDROGEN RECEPTORS IN PROSTATE-CANCER - A PROSPECTIVE-STUDY OF 63 CASES WITH LONG-TERM FOLLOW-UP

Background: Numerous problems are associated with biochemical androgen receptor (AR) assay performance and interpretation in prostatic cancer. The purpose of this study was to determine if a novel immunocytochemical AR assay performed on intact tissue sections would prove useful in prognosticating endocrine response and survival. Methods: A prospective study was done on 63 prostatic carcinomas maintained in liquid nitrogen for over a decade. The study used the peroxidase-antiperoxidase system and a polyclonal anti-AR antibody. Results: Marked tissue and cellular heterogeneity of nuclear AR was apparent. A cut-off of 10% AR-positive cells maximized assay prognostic efficiency. Frequency of positivity was 48% and correlated significantly with endocrine response (p = 0.03), time to progression (p = 0.0016), and survival (p = 0.02), but not with grade, stage, or ethnicity. Conclusions: This AR assay could be prognostically useful in the clinical management of prostate cancer and is suitable far use in the community hospital laboratory.