High Androgen Receptor mRNA Expression Is Independently Associated with Prolonged Cancer-Specific and Recurrence-Free Survival in Stage T1 Bladder Cancer

INTRODUCTION: High-risk non–muscle-invasive bladder cancer (NMIBC) remains challenging given the high probability of progression. Given that the androgen receptor (AR) has been discussed as a possible factor in the development and progression of bladder cancer, we investigated the predictive value of AR in stage pT1 NMIBC. MATERIALS AND METHODS: We retrospectively analyzed the clinical data and AR mRNA expression in 296 patients with stage pT1 NMIBC who underwent a transurethral resection of the bladder. The mRNA expression of the AR transcript variants 1 (AR1) and 2 (AR2) was measured by reverse transcription quantitative real-time polymerase chain reaction. AR expression was also correlated to KRT5 and KRT20 mRNA expression. RESULTS: Kaplan-Meier analysis indicated that high AR1 mRNA expression ≥35.47 is associated with statistically significant better recurrence-free survival (RFS) (P = .0007), progression-free survival (PFS) (P = .0420), and cancer-specific survival (CSS) (P = .0050). Multivariate Cox regression analysis revealed that high AR1 mRNA expression is an independent prognostic marker for RFS (P = .0029) and CSS (P = .0119). Spearman rank correlation revealed a significant positive association between mRNA expression of AR1 and KRT5 (rs: 0.3171, P