Abstract 2032
Background
Esophageal and gastric (EG) cancers stand for a considerable amount of cancer cases and deaths worldwide. Although addition of neoadjuvant and/or adjuvant therapy has led to an improved survival in patients with resectable tumours, there is still a great unmet need for novel treatment strategies and complementary biomarkers. This study examined the effect of neoadjuvant chemotherapy on the expression of programmed death receptor 1 (PD-1) and programmed death ligand 1 (PD-L1) in EG adenocarcinoma, as well as the associations of PD-1 and PD-L1 expression with histopathological response and clinical outcome.
Methods
Immunohistochemical expression of PD-1 on tumour-infiltrating immune cells (TIC) and of PD-L1 on tumour cells (TC) and TIC was assessed on paired pre-treatment biopsies, post-treatment resected primary tumours and a subset of paired lymph node metastases from a consecutive cohort of 148 patients with neoadjuvant +/- adjuvant treated EG adenocarcinoma.
Results
PD-1 expression was significantly higher in resected tumours and in lymph node metastases compared to biopsies, but the expression of PD-L1 TC and PD-L1 TIC was similar before and after neoadjuvant therapy. PD-1 expression was not associated with histopathological response or with survival. Positive PD-L1 TC expression in biopsies was significantly associated with histopathological response but not with survival, whereas positive PD-L1 TC expression in resected tumours signified a reduced overall survival. High PD-L1 TIC expression in biopsies, but not in resected tumours, was significantly associated with a prolonged overall survival.
Conclusions
Expression of PD-1, but not of PD-L1, is augmented after neoadjuvant treatment. Chemotherapy may however evoke more resistant subsets of PD-L1 positive TC, thus indicating a need for alternative treatment strategies in the adjuvant setting.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Lund University.
Funding
SUS Stiftelse och Donationer Fru Berta Kamprads Stiftelse Vetenskapliga rådet, Projektmedel för forsknings- och Utvecklingsarbete.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4331 - STING Agonist, ADU-S100, Yields Potent Antitumor Activity and Therapeutically Favorable Immune Profile in an Esophageal Adenocarcinoma Model
Presenter: Ali Zaidi
Session: Poster Display session 2
Resources:
Abstract
1770 - Increased assessment of HER2 in metastatic gastroesophageal cancer patients: a nationwide population-based cohort study
Presenter: Willemieke Dijksterhuis
Session: Poster Display session 2
Resources:
Abstract
3755 - A new docetaxel (DOC)-based triplet regimen does not improve the outcome of metastatic (M) or locally advanced (LA) gastric cancer (GC) as compared with an epirubicin (EPI) standard triplet regimen: a GISCAD trial.
Presenter: Roberto Labianca
Session: Poster Display session 2
Resources:
Abstract
2439 - The analysis of T cell subsets and clinical efficacy of immune checkpoint blockades in patients with advanced gastric cancer using multiplex immunohistochemistry
Presenter: Tae-yong Kim
Session: Poster Display session 2
Resources:
Abstract
2211 - First-line pembrolizumab (P), trastuzumab (T), capecitabine (C) and oxaliplatin (O) in HER2-positive metastatic esophagogastric adenocarcinoma.
Presenter: Yelena Janjigian
Session: Poster Display session 2
Resources:
Abstract
3046 - Monitoring patient-specific mutation in ctDNA and CTC for tumor response evaluation after neoadjuvant chemotherapy in locally advanced gastric cancer (NCT03425058)
Presenter: Tao Fu
Session: Poster Display session 2
Resources:
Abstract
4628 - Gastric cancer screening in BRCA 2 gene mutation carriers: should it be recommended?
Presenter: Inês Oliveira
Session: Poster Display session 2
Resources:
Abstract
2127 - Interim analysis of an observational/translational study for nivolumab treatment in advanced gastric cancer: JACCRO GC-08 (DELIVER trial)
Presenter: Yu Sunakawa
Session: Poster Display session 2
Resources:
Abstract
2264 - Prediction of S-1 adjuvant chemotherapy efficacy in Stage II/III gastric cancer treatment based on comprehensive gene expression analysis
Presenter: Masanori Terashima
Session: Poster Display session 2
Resources:
Abstract
2444 - Assessing the clinical utility of circulating tumour DNA through longitudinal liquid biopsy sampling in Oesophageal adenocarcinoma
Presenter: Emma Ococks
Session: Poster Display session 2
Resources:
Abstract