649P - PD-L1 expression in primary tumours and paired lymph node metastases in chemoradiotherapy-naïve esophageal and gastric adenocarcinoma: relationship...

Date 09 September 2017
Event ESMO 2017 Congress
Session Poster display session
Topics Oesophageal Cancer
Gastric Cancer
Gastrointestinal Cancers
Translational Research
Presenter Maria Svensson
Citation Annals of Oncology (2017) 28 (suppl_5): v209-v268. 10.1093/annonc/mdx369
Authors M. Svensson1, D. Borg1, C. Hedner1, J. Eberhard1, B. Nodin1, K. Leandersson2, K. Jirström3
  • 1Department Of Clinical Sciences Lund, Oncology And Pathology, Sweden, Lund University, 22185 - Lund/SE
  • 2Cancer Immunology, Department Of Translational Medicine, Lund University, Malmö, Sweden, Lund University, 22185 - Lund/SE
  • 3Department Of Clinical Sciences Lund, Oncology And Pathology, Lund University, Lund, Sweden, Lund University, 22185 - Lund/SE

Abstract

Background

Although neoadjuvant and/or adjuvant treatment enhances survival in patients with resectable esophageal and gastric (EG) cancer, the prognosis remains poor and there is a great need to identify novel treatment strategies and suitable biomarkers. The efficacy of immune-modulating therapies in EG cancer remains to be confirmed. Expression of programmed death ligand 1 (PD-L1) is, together with microsatellite instability (MSI) status, a putative biomarker of response to such therapies, but their prognostic value in EG cancer remains unclear. Therefore, the aim of this study was to examine the expression of PD-L1 in tumour cells (TC) and tumour-infiltrating immune cells (IC) in chemoradiotherapy-naïve primary EG tumours and paired lymph node metastases. Particular attention was given to the relationship with MSI status and prognosis.

Methods

PD-L1 expression in TC and IC was assessed by immunohistochemistry (IHC) on tissue microarrays with all primary tumours (n = 165) and paired lymph node metastases (n = 61) from a retrospective consecutive cohort of patients with chemoradiotherapy-naïve resected EG cancers. MSI was defined as loss of IHC expression of MLH1, MSH2, MSH2 or MSH6. Univariable and multivariable Cox regression analysis was used to calculate overall survival (OS).

Results

There was a significant correlation between TC and IC PD-L1 expression in primary tumours (p 

Conclusions

PD-L1 expression in TC does not differ significantly between primary tumours and lymph node metastases, PD-L1 expression in IC but not in TC is an independent favourable prognostic factor.

Clinical trial identification

Legal entity responsible for the study

Lund University

Funding

This study was supported by grants from the Swedish Cancer Society, the Swedish Research Council, the Mrs. Berta Kamprad Foundation, the Swedish Government Grant for Clinical Research (ALF), Lund University Faculty of Medicine, and the Lund University Hospital Research Grants.

Disclosure

All authors have declared no conflicts of interest.