title: The role of PD-L1 expression as a predictive biomarker in advanced non-small-cell lung cancer: a network meta-analysis.
abstract: BACKGROUND
  Tumor programmed death ligand one (PD-L1) expression has been studied in several trials in non-small-cell lung cancer.
  
  
  METHODS
  We assessed the potential role of PD-L1 expression according to Cochrane Collaboration's Guidelines.
  
  
  RESULTS
  13 studies with 1979 patients were included. Among 915 PD-L1 negative patients this rate was 13% (RR 2.08; 95% CI: 1.49-2.91; p < 0.01). The response rate has increased concurrent to the PD-L1 expression (Pearson's correlation, r = 0.43). PD-L1 expression was also related to better 24-weeks progression-free rate (RR 0.79; 95% CI: 0.71-0.89) and a trend toward better 1-year overall survival rate (RR 0.96; 95% CI: 0.87-1.06).
  
  
  CONCLUSIONS
  Taking this data in account, PD-L1 overexpression could not be currently considered a robust biomarker to tailor the immune checkpoint inhibitors treatment.
authors.affiliation: Division of Medical Oncology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Pedro N
authors.initials: PN
authors.lastname: Aguiar
authors.affiliation: Division of Medical Oncology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Ilka Lopes
authors.initials: IL
authors.lastname: Santoro
authors.affiliation: Division of Medical Oncology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Hakaru
authors.initials: H
authors.lastname: Tadokoro
authors.affiliation: Oncoclínicas do Brasil group, São Paulo, Brazil.|Department of Medical Oncology, Johns Hopkins University, Singapore.
authors.forename: Gilberto
authors.initials: G
authors.lastname: de Lima Lopes
authors.affiliation: Division of Medical Oncology, Federal University of São Paulo, São Paulo, Brazil.
authors.forename: Bruno Andraus
authors.initials: BA
authors.lastname: Filardi
authors.affiliation: Department of Population Studies, Abel Salazar Biomedical Institute, University of Porto, Porto, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Oliveira
authors.affiliation: Department of Medical Oncology, University of Athens School of Medicine, Athens, Greece.
authors.forename: Giannis
authors.initials: G
authors.lastname: Mountzios
authors.affiliation: Department of Biomedical Sciences & Medicine, University of Algarve, Faro, Portugal.|Faculty of Medicine, University of Porto, Porto, Portugal.
authors.forename: Ramon Andrade
authors.initials: RA
authors.lastname: de Mello
mesh_terms: D000818:Animals; D060890:B7-H1 Antigen / Q000235:genetics / Q000378:metabolism*; D054316:Biomarkers, Pharmacological / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000401:mortality; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D011237:Predictive Value of Tests; D011379:Prognosis; D016019:Survival Analysis
chemical_list: D060890:B7-H1 Antigen; D054316:Biomarkers, Pharmacological; D014408:Biomarkers, Tumor
keywords: PD1; anti-PDL1; clinical trials; lung cancer; meta-analysis; nivolumab; non-small-lung cancer; pembrolizumab