The aim of this study was to elucidate the rates and prognostic roles of programmed cell death ligand 1 (PD-L1) immunohistochemical (IHC) expression in various malignant tumors through a systematic review and meta-analysis.
The current study included 16,176 patients from 97 eligible studies. We investigated PD-L1 expression and its correlation with survival rate in various malignant tumors.
The estimated rate of PD-L1 IHC expression was 0.449 (95% confidence interval [CI] 0.404-0.495). The highest and lowest PD-L1 expression levels were found in thyroid cancer (0.829, 95% CI 0.781-0.868) and small-cell neuroendocrine carcinoma (0.005, 95% CI 0.000-0.080), respectively. PD-L1 expression was significantly correlated with poorer overall survival and disease-free survival rates (hazard ratios 1.276, 95% CI 1.097-1.486 and 1.304, 95% CI 1.034-1.644, respectively). However, PD-L1 IHC expression was significantly correlated with worse overall survival rates in patients with esophageal cancer and renal cell carcinoma and with worse disease-free survival rates in patients with colorectal cancer, hepatocellular carcinoma, and renal cell carcinoma.
Our results show that PD-L1 expression rates and the correlations with survival varied between tumor types. Detailed evaluation criteria for PD-L1 will have to be standardized before application to specific tumor types.
Int J Biol Markers 2017; 32(1): e68 - e74
Article Type: ORIGINAL RESEARCH ARTICLE
AuthorsJung-Soo Pyo, Guhyun Kang, Jung Yeon Kim
- • Received on 27/04/2016
- • Accepted on 27/06/2016
- • Available online on 27/07/2016
- • Published online on 02/03/2017
This article is available as full text PDF.
- Pyo, Jung-Soo [PubMed] [Google Scholar] 1, *
- Kang, Guhyun [PubMed] [Google Scholar] 2
- Kim, Jung Yeon [PubMed] [Google Scholar] 2, * Corresponding Author (firstname.lastname@example.org)
Department of Pathology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul - Republic of Korea
Department of Pathology, Inje University Sanggye Paik Hospital, Seoul - Republic of Korea
Department of Pathology, Eulji University Hospital, Daejeon, Republic of Korea
Jung-Soo Pyo and Guhyun Kang contributed equally to this study.