10PD - Programmed death ligand-1 (PDL1) and CD3 co-expression in patients with advanced stage EGFR mutant NSCLC treated with EGFR tyrosine kinase inhibitor...

Date 20 November 2015
Event ESMO Symposium on Immuno-Oncology 2015
Session Poster Discussion session
Topics Anti-Cancer Agents & Biologic Therapy
Non-Small-Cell Lung Cancer, Metastatic
Cancer Immunology and Immunotherapy
Presenter Ross Soo
Citation Annals of Oncology (2015) 26 (suppl_8): 1-4. 10.1093/annonc/mdv513
Authors R.A. Soo1, H..R. Kim2, B.R. Asuncion3, Z. Fazreen3, M.F.M. Omar3, M.C. Herrera3, J.S.Y. Lim3, G. Sia3, R. Soong3, B. Cho2
  • 1Haematology-oncology, National University Cancer Institute, Singapore, 119074 - Singapore/SG
  • 2Medical Oncology, Yonsei Cancer Center Yonsei University, Seoul/KR
  • 3Cancer Science Institute Of Singapore, National University of Singapore, Singapore/SG

Abstract

Aim

The objective of this study was to determine the association between tumoral and immune cell PDL1 expression and clinical characteristics in NSCLC patients treated with first line EGFR TKI.

Methods

Tumors of 90 patients with advanced stage NSCLC harboring EGFR sensitizing mutations and treated with first line EGFR TKI were analyzed. All tumor samples were obtained within 3 months of starting therapy. Double staining for CD3 and PDL1 was performed by immunohistochemistry. PDL1 expression in tumour membrane, and PDL1 and CD3 expression in tumor and stromal immune cells were segmented and quantified using the Vectra slide imaging system (Perkin Elmer, Waltham, MA). Tumor membrane expression of PD-L1 was calculated as a H-Score. Immune cell density (ICD) of PD-L1 was calculated as the percentage of immune-shaped cells expressing PD-L1 of immune-shaped cells expressing CD3.

Results

The median age of patients was 62 (range 34-88) years, 64 (71%) were female, 69 (77%) were never smokers, and 43 (48%) harbored EGFR exon 19 deletion. Multimodal distributions of CD3 and PD-L1 expression were observed, suggesting that there may be distinct NSCLC subtypes according to CD3 and PD-L1 expression. CD3+ cells were observed in the stroma of 99% of cases, but in the tumor of only 46% of cases, suggesting CD3+ cells may be restricted from tumor infiltration in many cases. There was no association between PDL1 or CD3 expression with response rate or time to progression.

Conclusions

CD3+ cells may be restricted from tumor infiltration in a proportion of NSCLC tumors. PDL1 + ve immune cells are rare in this patient population. PDL1 expression in tumor membrane and immune cells may not be associated with outcome in NSCLC patients harboring EGFR mutations and treated with EGFR TKIs.

Clinical trial identification

Disclosure

All authors have declared no conflicts of interest.