Checkpoint inhibition has emerged as new therapeutic option in muscle-invasive bladder cancer. The objective of the present study was to evaluate the prognostic role of PD1 and PDL1 expression in non-muscle-invasive bladder cancer (NMIBC) and establish an objective measuring method using RNA quantification.
We retrospectively analyzed clinical data and formalin-fixed paraffin-embedded tissues (FFPE) of patients with stage pT1 NMIBC who underwent transurethral resection of the bladder. mRNA expression of PD1, PDL1 and CD3 was measured by single step RT-qPCR and correlated to clinicopathological parameters, recurrence-free survival (RFS), progression-free survival (PFS) and carcinoma-specific survival (CSS).
We have analyzed 334 patients with NMIBC at stage pT1 for mRNA analysis. Data from 296 patients (79% male, median age: 72 years) could be used. Spearman correlation revealed significant associations between mRNA expressions of PD1/PDL1 (ρ: 0.6024, p < 0.0001), CD3/PDL1 (ρ: 0.5728, p < 0.0001) and CD3/PD1 (ρ: 0.7005, p < 0.0001). Kaplan-Meier analysis revealed that high PDL1 mRNA expression (≥ 33.83) is a favorable prognostic factor with regard to better RFS (p = 0.0018), PFS (p = 0.021) and CSS (p = 0.012). Multivariate Cox-regression analysis proved PDL1 expression to be an independent prognosticator for RFS [HR 0.48 (0.31-0.72), p = 0.0005], PFS [HR 0.45 (0.24-0.80), p = 0.0059] and CSS [HR 0.31 (0.13-0.67), p = 0.0021].
High mRNA expression of PDL1 predicts improved RFS, PFS and CSS of pT1 NMIBC. Following prospective validation, this objective measurement of PD-L1 might help stratify patients with NMIBC for immunotherapy and identify patients who might benefit from early cystectomy.
Cancer immunology, immunotherapy : CII. 2017 Nov 17 [Epub ahead of print]
Johannes Breyer, Ralph M Wirtz, Wolfgang Otto, Philipp Erben, Thomas S Worst, Robert Stoehr, Markus Eckstein, Stefan Denzinger, Maximilian Burger, Arndt Hartmann
Department of Urology, Caritas St. Josef Medical Center, University of Regensburg, Landshuter Str. 65, 93053, Regensburg, Germany. ., STRATIFYER Molecular Pathology GmbH, Cologne, Germany., Department of Urology, Caritas St. Josef Medical Center, University of Regensburg, Landshuter Str. 65, 93053, Regensburg, Germany., Department of Urology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany., Institute of Pathology, University of Erlangen-Nuremberg, Erlangen, Germany.