Clinicopathological and prognostic significance of PD-L1 expression in colorectal cancer: a systematic review and meta-analysis

• Published in: World journal of surgical oncology Vol. 17; no. 1; p. 4
• Main Authors: Shen, Zefeng, Gu, Lihu, Mao, Danyi, Chen, Manman, Jin, Rongjia
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 04.01.2019; BioMed Central; BMC
• Subjects: Analysis; Apoptosis; B cells; B7-H1 Antigen - metabolism; Biomarkers, Tumor - metabolism; Cancer; Clinicopathological features; Colorectal cancer; Colorectal carcinoma; Colorectal Neoplasms - diagnosis; Colorectal Neoplasms - metabolism; Data processing; Development and progression; Health aspects; Humans; Immune system; Immunoassay; Immunotherapy; Ligands; Ligands (Biochemistry); Lymphocytes; Medical prognosis; Medical research; Meta-analysis; Microsatellite instability; Mortality; Operating systems (Software); Patients; PD-1 protein; PD-L1 expression; PD-L1 protein; Prognosis; Stability; Systematic review; Tumor markers; Tumors; China; PD-L1 expression; Clinicopathological features; Prognosis; Colorectal cancer; Meta-analysis
• ISSN: 1477-7819; 1477-7819
• DOI: 10.1186/s12957-018-1544-x

To analyze the prognostic value of programmed death factor ligand 1 (PD-L1) in colorectal cancer. Electronic databases, such as PubMed, Web of Science, Embase, and Cochrane library, were searched to identify studies evaluating the PD-L1 expression and overall survival (OS) in these patients. Afterwards, the relevant data were extracted to perform the meta-analysis. A total of 3481 patients were included in 10 studies. The combined hazard ratio (HR) was 1.22 (95%CI = 1.01-1.48, P = 0.04), indicating that high expression of PD-L1 was significantly correlated with poor prognosis of colorectal cancer. Apropos of clinicopathological features, the merged odds ratio (OR) exhibited that highly expressed PD-L1 was firmly related to lymphatic invasion (OR = 3.49, 95%CI = 1.54-7.90, P = 0.003) and advanced stage (OR = 1.77, 95%CI = 1.41-2.23, P < 0.00001), but not correlative with patients' gender, microsatellite instability, or tumor location. The expression of PD-L1 can be utilized as an independent factor in judging the prognosis of colorectal cancer, and patients with advanced cancer or lymphatic invasion are more likely to express PD-L1. This conclusion may lay a theoretical foundation for the application of PD-1/PD-L1 immunoassay point inhibitors but still needs verifying by sizeable well-designed cohort studies.