title: Programmed cell death-ligand 1 expression predicts survival in patients with gastric carcinoma with microsatellite instability.
abstract: Programmed death-ligand 1 (PD-L1) is expressed in a subgroup of gastric cancers that may benefit from immunotherapy. Microsatellite instability-high (MSI-H) is a potential predictive factor for response to immunotherapy targeting the PD-1 or its ligand PD-L1. The relationship between PD-L1 expression and MSI-H status remains poorly understood. In this study, we investigated PD-L1 expression in patients with MSI-H gastric cancer. We analyzed PD-L1 expression in 78 MSI-H gastric cancer tissue samples using immunohistochemistry. PD-L1 expression was classified as expression on tumor cells or on immune cells. We observed PD-L1 expression in 48 gastric cancer samples (61.5%), consisting of 7 (9.0%) cases with tumor PD-L1 expression and 47 (60.3%) cases with immune cell PD-L1 expression. Immune cell PD-L1 expression was frequently associated with intestinal type cancer by the Lauren classification (p = 0.015), with a lower risk of lymph node metastasis (p = 0.027) and lower tumor stages (p = 0.029) compared to MSI-H gastric cancers without PD-L1 expression. Moreover, immune cell PD-L1 expression was an independent favorable prognostic factor for overall survival (versus PD-L1 negative; hazard ratio, 3.451; 95% confidence interval, 1.172-12.745; p = 0.025). In MSI-H gastric cancer, PD-L1 expression was observed to be independently associated with a longer survival.
authors.affiliation: Department of Pathology, Soonchunhyang University Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan, Korea.
authors.forename: Junhun
authors.initials: J
authors.lastname: Cho
authors.affiliation: Department of Medicine, Division of Hematology-Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jeeyun
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Pathology and Translational Genomics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Heejin
authors.initials: H
authors.lastname: Bang
authors.affiliation: Department of Medicine, Division of Hematology-Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Seung Tae
authors.initials: ST
authors.lastname: Kim
authors.affiliation: Department of Medicine, Division of Hematology-Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Se Hoon
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ji Yeong
authors.initials: JY
authors.lastname: An
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Min Gew
authors.initials: MG
authors.lastname: Choi
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Joon Ho
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Tae Sung
authors.initials: TS
authors.lastname: Sohn
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jae Moon
authors.initials: JM
authors.lastname: Bae
authors.affiliation: Department of Medicine, Division of Hematology-Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Won Ki
authors.initials: WK
authors.lastname: Kang
authors.affiliation: Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sung
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Pathology and Translational Genomics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Kyoung-Mee
authors.initials: KM
authors.lastname: Kim
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000401:mortality / Q000473:pathology*; D000328:Adult; D000368:Aged; D060890:B7-H1 Antigen / Q000032:analysis / Q000096:biosynthesis*; D014408:Biomarkers, Tumor / Q000032:analysis; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D016246:Lymphocytes, Tumor-Infiltrating / Q000378:metabolism; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D013274:Stomach Neoplasms / Q000378:metabolism / Q000401:mortality / Q000473:pathology*
chemical_list: D060890:B7-H1 Antigen; D014408:Biomarkers, Tumor; C423236:CD274 protein, human
keywords: gastric cancer; immune; prognosis; programmed death-ligand 1; therapy