Androgen Receptor Predicts First and Multiple Recurrences in Non-Muscle Invasive Urothelial Carcinoma of the Bladder

The aim of this study is to investigate the role of androgen receptor (AR) expression on clinicopathologic characteristics, first recurrence free survival (RFS), progression free survival (PFS) and multiple recurrences in non-muscle invasive bladder cancer (NMIBC). AR expression in 40 paraffin-embedded specimens of primarily diagnosed NMIBC after transurethral resection was examined by immunohistochemistry using a monoclonal AR antibody. Associations between AR expression and clinicopathologic features and prognosis were statistically assessed. Multivariate Cox proportional hazards model was applied for evaluating predictive factors on RFS and PFS. For multiple recurrences, we used the Andersen-Gill model. AR was positive in 20/40 (50%) cases. Twenty-three patients (57.5%) had no recurrence, 10 (25.0%) had one recurrence, and 7 (17.5%) experienced more than one recurrence. AR expression and clinicopathologic features were not significantly correlated (P>0.05). Univariate analyses showed that AR expression was significantly associated with RFS and PFS (P<0.05). Via multivariate analyses, positive AR expression was significantly associated with lower risk of first recurrence (hazard ratio (HR)=0.265; 95% confidence interval (95% CI)=0.084-0.829; P=0.022). Multivariate analysis of PFS was not feasible in our cohort. Using the multivariate Andersen-Gill model, positive AR expression in the primary tumor was an independent factor predicting lower risk of multiple recurrences (HR=0.387, 95% CI=0.161-0.927, P=0.033). Androgen receptor expression is associated with first and multiple recurrences in NMIBC.