title: Favorable Disease-free Survival Associated with Programmed Death Ligand 1 Expression in Patients with Surgically Resected Small-cell Lung Cancer.
abstract: BACKGROUND
  The prognostic significance of programmed death ligand 1 (PD-L1) has been reported in non-small cell lung cancer; however, the significance of PD-L1 expression in patients with resected small-cell lung cancer (SCLC) remains to be clarified.
  
  
  METHODS
  Forty patients with SCLC whose resected specimens were available for immunohistochemistry for PD-L1 were evaluated to determine the association between its expression and the clinicopathological factors and prognosis.
  
  
  RESULTS
  Among 40 patients, PD-L1 was expressed in tumor cells (TCs) of six (15%), tumor-infiltrating cells (ICs) of 16 (40%), and TCs and/or ICs cells of 18 (45%) patients. Patients with PD-L1-positve ICs and TCs and/or ICs exhibited significantly longer disease-free survival than those without PD-L1-expression (hazard ratio (HR)=0.268; 95% confidence interval (CI)=0.100-0.645; p=0.003 and HR=0.301; 95% CI=0.118-0.702; p=0.005, respectively).
  
  
  CONCLUSIONS
  This study provides important evidence on the prognostic value of the PD-L1 expression in resected SCLC patients.
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan gouji104kawa@gmail.com.
authors.forename: Gouji
authors.initials: G
authors.lastname: Toyokawa
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Takada
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Haratake
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Shinkichi
authors.initials: S
authors.lastname: Takamori
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Takaki
authors.initials: T
authors.lastname: Akamine
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Katsura
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Fujishita
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Shoji
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Okamoto
authors.affiliation: Department of Anatomic Pathology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yoshinao
authors.initials: Y
authors.lastname: Oda
authors.affiliation: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Maehara
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D060890:B7-H1 Antigen / Q000096:biosynthesis* / Q000235:genetics; D014408:Biomarkers, Tumor / Q000096:biosynthesis* / Q000235:genetics; D018572:Disease-Free Survival; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D055752:Small Cell Lung Carcinoma / Q000235:genetics / Q000473:pathology / Q000601:surgery*
chemical_list: D060890:B7-H1 Antigen; D014408:Biomarkers, Tumor
keywords: Small-cell lung cancer; immunotherapy; prognosis; programmed death ligand 1; surgery