The Feasibility and Diagnostic Adequacy of PD-L1 Expression Analysis Using the Cytoinclusion Technique in Bladder Cancer: A Prospective Single-Center Study.

Background: Programmed death-ligand 1 (PD-L1) expression has been recognized as a potential biomarker for various cancers, yet its diagnostic and prognostic significance in urothelial bladder cancer (BCa) requires further investigation. Methods: In this prospective single-center study, we aimed to assess the feasibility and diagnostic adequacy of PD-L1 expression analysis using cytoinclusion in BCa patients. We enrolled consecutive patients undergoing endoscopic transurethral resection of bladder tumor (TURBT), repeat TURBT, or robot-assisted radical cystectomy. Urinary and tissue specimens were collected from these patients for cytoinclusion and histopathological analysis to evaluate PD-L1 expression. Results: Out of 29 patients, PD-L1 expression was detected from cytoinclusion in 42.8% (3 out of 7), 10% (1 out of 10), and 66.8% (8 out of 12) of patients with negative/papilloma, low-grade, and high-grade tumors, respectively. Conversely, histopathological analysis identified PD-L1 expression in 57.2% (4 out of 7), 30% (3 out of 10), and 83.3% (10 out of 12) of patients with negative/papilloma, low-grade, and high-grade tumors, respectively. The diagnostic concordance between cytoinclusion and histopathology was 85.7%, 80%, and 83.3% in patients with negative/papilloma, low-grade, and high-grade tumors, respectively. Conclusions: Our study underscores the promise of cytoinclusion as a minimally invasive method for quantifying urinary PD-L1 percentages. This approach could serve as both a potential prognostic and diagnostic indicator, easily obtainable from urine samples. Standardizing this technique could facilitate its widespread use as a valuable tool.

Journal of clinical medicine. 2024 Jul 12*** epublish ***

Luca Di Gianfrancesco, Isabella Monia Montagner, Debora Tormen, Alessandro Crestani, Antonio Amodeo, Paolo Corsi, Davide De Marchi, Eugenio Miglioranza, Giuliana Lista, Francesca Simonetti, Gian Maria Busetto, Martina Maggi, Filippo Marino, Antonio Scapinello, Angelo Porreca

Department of Urology, Veneto Institute of Oncology (IOV)-IRCCS, Headquarter of Castelfranco Veneto, 35128 Padua, Italy., Anatomy and Pathological Histology Unit, Veneto Institute of Oncology IOV-IRCCS, 35128 Padua, Italy., Department of Urology, Ospedale Santa Maria Della Misericordia di Udine, 33100 Udine, Italy., Department of Urology, University of Foggia, 71122 Foggia, Italy., Department of Urology, Sapienza University, 00185 Rome, Italy., Department of Urology, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, University of Sacre Heart, 00168 Rome, Italy.