Androgen receptor levels in prostate cancer epithelial and peritumoral stromal cells identify non-organ confined disease.

Although up to 30% of men who undergo radical prostatectomy for clinically organ-confined prostate cancer will relapse with disseminated disease, currently it is not possible to predict these patients. Androgen receptor (AR) immunoreactivity in stromal and epithelial compartments of tumor foci was evaluated by video image analysis in 53 radical prostatectomy specimens. Kaplan-Meier and Cox Regression analyses were used to determine whether AR immunostaining was related to rate and risk of relapse, respectively. Ninety-eight percent (52/53) of the tumors contained AR positive malignant epithelial cells. Kaplan-Meier analysis indicated that patients with high AR levels (>64% AR positive nuclear area) in the malignant epithelial cells or low AR levels (<or=45% AR positive nuclear area) in the peritumoral stroma cells, were more likely to relapse earlier following radical prostatectomy. The shortest time to relapse and the highest relapse rate was for patients with both high AR in the malignant epithelial cells and low AR in the peritumoral stromal cells. These findings suggest that AR is an important determinant of disease relapse in early stage prostate cancer, and that altered AR levels in the malignant epithelial cells or in the peritumoral stroma is indicative of non-organ confined prostate cancer.