MP84-13 PROGRAMMED DEATH LIGAND-1 (PD-L1) EXPRESSION STATUS IN PENILE SQUAMOUS CELL CARCINOMA TUMOR CELLS AND TUMOR INFILTRATING IMMUNE CELLS

Abstract

You have accessJournal of UrologySexual Function/Dysfunction: Penis/Testis/Urethra: Benign Disease & Malignant Disease II1 Apr 2018MP84-13 PROGRAMMED DEATH LIGAND-1 (PD-L1) EXPRESSION STATUS IN PENILE SQUAMOUS CELL CARCINOMA TUMOR CELLS AND TUMOR INFILTRATING IMMUNE CELLS Jennifer Rider, Alyssa Harlow, Francesca Giunchi, Jessica Carlsson, Peter Kirrander, Michelangelo Fiorentino, Ove Andren, and Sabina Davidsson Jennifer RiderJennifer Rider More articles by this author , Alyssa HarlowAlyssa Harlow More articles by this author , Francesca GiunchiFrancesca Giunchi More articles by this author , Jessica CarlssonJessica Carlsson More articles by this author , Peter KirranderPeter Kirrander More articles by this author , Michelangelo FiorentinoMichelangelo Fiorentino More articles by this author , Ove AndrenOve Andren More articles by this author , and Sabina DavidssonSabina Davidsson More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.2781AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Studies of PD-L1 expression in penile squamous cell carcinoma (SCC) have been small or have used only one anti-PD-L1 antibody for immunohistochemical (IHC) staining, despite evidence of variability in antibody specificity. Using a large penile SCC archival tumor tissue cohort, our objective was to compare PD-L1 protein expression status in tumor and tumor infiltrating immune cells (TIICs) using two different antibodies, and relate expression to clinical and tumor characteristics. METHODS Among 220 patients treated for penile SCC in Orebro, Sweden between 1984-2008, PD-L1 IHC staining was undertaken on three tumor cores per patient using two anti-PD-L1 rabbit monoclonal antibodies (SP142, Roche; 28-8, Abcam). Specific membranous and/or cytoplasmic staining was independently evaluated by two uro-pathologists (F.G and M.F) blinded to all clinical data. The percentage of PD-L1 staining in tumor cells and TIICs were evaluated separately. Immunostaining was scored using 3 categories of % positive cells: <5%; >5% to <50%; and >50%. RESULTS Positive staining most often occurred in <5% of cells, so subsequent analyses only considered any vs. no staining in at least one core. For both antibodies, PD-L1 expression was observed more frequently in TIICs than in tumor cells (45.0% vs. 7.3% for SP-142; 64.2% vs 32.1% for 28-8). Positive TIIC staining with SP142 was associated with more poorly differentiated tumors (54.3% vs 34.2% grade 2/3; p=0.02), advanced T-stage (24.2% vs 10.2% stage T3; p=0.004), advanced pT stage (16.1% vs. 8.5% stage pT3; p=0.03), and a lower frequency of HPV-positive tumors (52.5% vs 72.5%; p=0.01). Positive staining in tumor with 28-8 was also associated with higher grade (65.2% vs. 39.9% grade 2/3; p=0.002), advanced T-stage (25.4% vs. 12.5% stage T3; p<0.0001), and advanced pT stage (18.5% vs 9.0% stage pT3; p=0.02). PD-L1 expression in tumor was marginally associated with increased penile cancer-specific mortality (18.8 vs. 6.2%, p=0.06 for SP142; 12.5% vs 4.9%, p=0.05 for 28-8). CONCLUSIONS PD-L1 expression in tumor and TIICs has potential prognostic value for penile cancer. In TIICs, the SP142 antibody was more prognostic, while positive tumor staining using the 28-8 antibody was more strongly associated with clinicopathological variables. The results provide further rationale for targeting immune checkpoint inhibitor pathways in advanced penile SCC. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e1129-e1130 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Jennifer Rider More articles by this author Alyssa Harlow More articles by this author Francesca Giunchi More articles by this author Jessica Carlsson More articles by this author Peter Kirrander More articles by this author Michelangelo Fiorentino More articles by this author Ove Andren More articles by this author Sabina Davidsson More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...