Back to 2015 Joint Annual Meeting
PDL1 Expression in Upper Tract Urothelial Carcinoma
Jen-Jane Liu1, Gunes Guner1, Kazutoshi Fujita2, Alex Baras1, Janis Taube1, Noah M Hahn1, Charles Drake1, George Netto1, Trinity J Bivalacqua1 1Johns Hopkins Hospital, Baltimore, MD;2Osaka Graduate University Graduate School of Medicine, Osaka, Japan
Introduction: Anti-programmed death ligand (PDL1) therapy has shown promising results in tumors with proven PDL 1 expression, including advanced stage urothelial carcinoma of the bladder, however, little is known about PDL1 expression in upper tract urothelial carcinoma (UTUC). We evaluated PDL1 expression in a large series of UTUC. Materials & Methods: We studied 99 patients with UTUC. Tissue microarrays TMAs were stained with PD-L1 (Cell-Signaling, E1L3N, 1:100). The degree of tumoral PDL1 was manually scored. PDL1 positivity was defined as >5% tumoral PDL1 staining. The primary outcome of the study was the percentage of tumor cells staining positive for PDL1. Results: 62% of our cohort had ≥pT2 UTUC. Overall, 45% of tumors were of the renal pelvis, 50% of the ureter, and 4% were of both. The overall rate of PDL1 positivity in our cohort was 15%. For patients with ≥pT2 disease, the rate of PDL1 positivity was 18%. For patients with <pT2 disease, the rate of PDL1 positivity was 11%. Patients with pT4 disease showed the highest rates of PDL1 positivity (4/6, 67%). Conclusions: PDL1 positivity was observed in 15% of patients in this cohort of UTUC, with high rates of positivity in advanced stage disease. Anti-PDL1 therapy is an attractive therapeutic target for patients with UTUC, given that neoadjuvant therapy is underutilized and many patients may not be candidates for standard platinum-based therapies in an adjuvant setting. Further studies will be needed to evaluate clinical response rates in UTUC.
Back to 2015 Joint Annual Meeting
|