Intratumoural PD-L1 expression is associated with worse survival of patients with Epstein–Barr virus-associated gastric cancer
This study investigated the clinical relevance and prognostic impact of the overall expression of programmed cell death protein ligand-1 (PD-L1) and programmed cell death protein ligand-2 (PD-L2), in patients with Epstein–Barr virus-associated gastric cancer (EBVaGC).
After reviewing 1318 consecutive cases of surgically resected or endoscopic submucosal dissected gastric cancers, the expression status of PD-L1 and PD-L2 in 120 patients with EBVaGC identified by EBV-encoded RNA in situ hybridisation was retrospectively analysed using immunohistochemistry (IHC). For each IHC marker, positivity was separately in intraepithelial tumour cells (iTu-) and immune cells in the tumour stroma area (str-).
Among 116 eligible patients, 57 (49.1%) and 66 patients (56.9%) were determined as iTu-PD-L1-positive and str-PD-L1-positive, respectively, whereas 23 (21.6%) and 45 patients (38.8%) were determined as iTu-PD-L2 positive and str-PD-L2 positive, respectively. Intraepithelial tumour cell PD-L1 positivity was found to be significantly associated with lymph node (LN) metastasis (P=0.012) and a poor disease-free survival (DFS) (P=0.032), yet not overall survival (P=0.482). In a multivariate analysis, iTu-PD-L1 positivity was independently associated with a poor DFS (P=0.006, hazard ratio=12.085). In contrast, str-PD-L2-positivity was related to a lower T category (P=0.003), absence of LN metastasis (P=0.032) and perineural invasion (P=0.028). Intraepithelial tumour cell and str-PD-L2 positivity showed a trend towards an improved DFS, although not significant (P=0.060 and P=0.073, respectively).
Intraepithelial tumour cells PD-L1 expression can be used to predict a poor outcome in patients with EBVaGC and can represent a rational approach for PD-1/PD-L pathway-targeted immunotherapy.
Publisher URL: https://www.nature.com/articles/bjc2017369
Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.
Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.