The prognostic value of programmed cell death protein ligand 1 in patients with non-muscle-invasive bladder cancer treated with bacille Calmette–Guérin immunotherapy: Current status

Abstract

The prognostic value of programmed cell death protein ligand 1 in patients with non-muscle-invasive bladder cancer treated with bacille Calmette-Guérin immunotherapy: Current status, Arab Journal of Urology,

Human epidermal growth factor receptor 2 (HER2) and the future of bladder carcinoma

“…To this extent, both United States Food and Drug Administration (FDA)-approved programmed cell death protein ligand 1 (PD-L1) and fibroblast growth factor receptors (FGFRs) have been studied as useful biomarkers for predicting the efficacy of immune checkpoint inhibitors in BC. Additionally, a recent literature review published in this journal by Nowak et al [4] found an association between increased PD-L1 expression and BCG unresponsiveness in non-MIBC (NMIBC). Unfortunately, current evidence is inconsistent and incorporating these biomarkers into clinical practice is still premature, with further multicentre randomised trials needed to make definitive conclusions.…”

Integrating the PD-L1 Prognostic Biomarker in Non-Muscle Invasive Bladder Cancer in Clinical Practice—A Comprehensive Review on State-of-the-Art Advances and Critical Issues

“…Putative reasons which may contribute to affect the consistency and comparability of available findings in this setting (and more generally the assessment of PD-L1 expression as a biomarker in BC) are (1) intrinsic to the study population, including a small number of patients overall [50,58,62], an exceedingly low recurrence rate after BCG treatment, and/or unbalanced subgroup size (i.e., BCG responders vs. non responders) [53]; (2) intrinsic to the treatment, including the frequency and/or timing of BCG administration and type of BCG reagents; (3) intrinsic to the method, such as PD-L1 assessment through heterogeneous assays, antibody clones, cellular populations, scoring systems, and cut-off points (see next section); and (4) intrinsic to the tumor/tissue sample, due to the intra-tumoral heterogeneity of PD-L1 expression and the dynamic nature of the tumor microenvironment [66,67]. Furthermore, the constantly changing of the molecule over time (temporal heterogeneity) has been proven by the discrepancy over different tumor stages, as well as between metastatic sites and corresponding primary tumors, revealed by several authors [68,69].…”