World J Urol. 2020 Jul 16. doi: 10.1007/s00345-020-03358-x. Online ahead of print.
PURPOSE: The impact of sex hormones on cancer immunotherapy remains controversial. Androgens, via the androgen receptor (AR), may impact the success of immune checkpoint blockade. This study characterizes AR and programmed death ligand-1 (PD-L1) expression in bladder tumors with long clinical follow-up.
METHODS: AR and PD-L1 expression was analyzed using immunohistochemistry on 143 transurethral resection (TUR) and 203 radical cystectomy (RC) specimens. Descriptive statistics and survival analyses assessed the relationship of AR and PD-L1 staining with clinical outcomes of tumor recurrence, progression, and overall survival.
RESULTS: AR expression was observed in a higher proportion of TUR than RC specimens (59% vs 35%, p < 0.001). High immune cell (IC) PD-L1 expression was associated with higher stage and grade. Patients with the combination of an absence of AR expression and the highest (> 10%) IC PD-L1 expression in TUR tumors had an increased risk of recurrence and progression. In RC specimens, the expression of AR increased the risk of local recurrence (adjusted hazard ratio (HR) 2.09, 95% CI 0.98-4.45), which was even higher among patients who also had IC PD-L1 expression (HR 4.16, 95% CI 1.28-13.52). For 28 paired metastatic lymph nodes among RC patients, tumor cell PD-L1 expression was significantly correlated (r = 0.48, p = 0.01), while no relationship with IC PD-L1 expression was observed.
CONCLUSIONS: The expression of AR and its relationship to clinical outcomes appears to vary between non-muscle invasive and muscle-invasive bladder cancer. Our results support the role of IC PD-L1 expression as an independent risk factor for bladder cancer outcomes.