862P - PD-L1 expression in muscle-invasive bladder cancer cystectomy specimens and lymph node metastasis

Date 27 September 2014
Event ESMO 2014
Session Poster Display session
Topics Urothelial Cancers
Pathology/Molecular Biology
Basic Scientific Principles
Presenter Deborah Mukherji
Citation Annals of Oncology (2014) 25 (suppl_4): iv280-iv304. 10.1093/annonc/mdu337
Authors D. Mukherji1, M. Jabbour2, M. Saroufim2, S. Temraz1, R. Nasr3, A. Shamseddine1, A. Tawil2
  • 1Department Of Hematology Oncology Po Box: 11-0236, American University of Beirut Medical Center, 1107 2020 - Beirut/LB
  • 2Department Of Pathology Po Box: 11-0236, American University of Beirut Medical Center, 1107 2020 - Beirut/LB
  • 3Department Of Urology Po Box: 11-0236, American University of Beirut Medical Center, 1107 2020 - Beirut/LB

Abstract

Aim

The programmed death-1 (PD-1) pathway negatively regulates T-cell activation and has been shown to play an important role in regulating antitumor host immunity. Monoclonal antibodies directed against PD-1 or it's ligand PD-L1 have demonstrated promising clinical activity against several solid tumor types. Preliminary data have suggested a relationship between PD-L1 expression on tumor cells and objective response. Immunological responses in bladder cancer are known to be relatively well preserved with immunotherapy routinely used for early disease. We sought to investigate the frequency of PD-L1 overexpression in muscle-invasive bladder cancer cystectomy specimens and lymph nodes metastasis to investigate the feasibility of using this as a biomarker to select patients for PD-1/ PD-L1 directed therapy.

Methods

Cases of radical cystectomy for muscle-invasive bladder cancer were identified from pathology records at our institution. Representative slides from archived tumor blocks were incubated with anti-PD-L1 antibody (clone 5H1). PD-L1 positivity was defined by a 5% expression threshold.

Results

54 radical cystectomy specimens with muscle-invasive bladder cancer were reviewed. Patient characteristics: female 4/54, male 50/54, median age 69 (range 30-88). Tumor characteristics: 100% high-grade transitional cell carcinoma, pT2 19/54 (35%), pT3 31/54 (57%), pT4 4/54 (7%), pN1 17/54 (31%). PD-L1 was overexpressed in 5/54 cases (9%), all of these cases were at least pT3a. Of 4/5 PD-L1 positive cases with associated lymph node metastasis, corresponding overexpression of PD-L1 was seen in only 2 of these 4 specimens.

Conclusions

PD-L1 was overexpressed in 9% of muscle-invasive bladder cancer cystectomy specimens in this cohort with corresponding PD-L1 overexpression in the lymph node metastasis of only 2 of 4 cases with lymph node metastatic disease.

Disclosure

D. Mukherji: Honoraria and travel support recieved from Sanofi and Janssen. All other authors have declared no conflicts of interest.