title: Prognostic implications of PD-L1 expression in patients with soft tissue sarcoma.
abstract: The PD-1/PD-L1 axis plays a paramount role in the immune escape of tumor cells by negative regulation of T-cell functions. The aim of the present study was to characterize the PD-L1 expression pattern and its clinical implication in soft-tissue sarcomas (STS).
  
  
  
  We analyzed PD-L1 expression in 82 STS patients with 5 subtypes: rhabdomyosarcoma, synovial sarcoma, Ewing sarcoma, epithelioid sarcoma, and mesenchymal chondrosarcoma.
  
  
  
  The median age at diagnosis was 26 (range: 1-78) and the male to female ratio was 1.6. The majority (80 %) of patients showed locoregional disease rather than metastatic disease at diagnosis. Thirty-five cases (43 %) showed PD-L1 expression and the proportion of PD-L1 expression was significantly different according to histologic subtypes (P = 0.004); highest in epithelioid sarcoma (100 %, 7/7), followed by synovial sarcoma (53 %, 10/19), rhabdomyosarcoma (38 %, 12/32), and Ewing sarcoma (33 %, 6/18), while it was not expressed in mesenchymal chondrosarcoma (0 %, 0/6). STS patients with PD-L1 expression had worse overall survival compared with those without PD-L1 expression (5-year survival rate: 48 % vs. 68 %, P = 0.015). The Cox proportional hazard model adjusted for histologic subtype, initial metastasis, and PD-L1 expression showed that PD-L1 expression was significantly associated with shorter overall survival (P = 0.037, HR 2.57, 95 % CI 1.060-6.231).
  
  
  
  We have confirmed PD-L1 expression in various STS of young population and demonstrated its independent negative prognostic role, thereby suggesting the PD-1/PD-L1 axis as a potential therapeutic target for the treatment of young STS patients.
authors.affiliation: Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, 134 Shinchondong, Seodaemun-gu, Seoul, 03722, Korea.|Medical Oncology, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
authors.forename: Chan
authors.initials: C
authors.lastname: Kim
authors.affiliation: Department of Pathology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Kim
authors.affiliation: Oncology, Merck Sharp & Dohme, Seoul, Korea.
authors.forename: Hun
authors.initials: H
authors.lastname: Jung
authors.affiliation: Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, 134 Shinchondong, Seodaemun-gu, Seoul, 03722, Korea.|Medical Oncology, CHA Bundang Medical Center, CHA University, Seongnam, Korea.
authors.forename: Hong Jae
authors.initials: HJ
authors.lastname: Chon
authors.affiliation: Department of Pediatric Hemato-Oncology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jung Woo
authors.initials: JW
authors.lastname: Han
authors.affiliation: Department of Orthopedic Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kyoo-Ho
authors.initials: KH
authors.lastname: Shin
authors.affiliation: Department of Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Hyuk
authors.initials: H
authors.lastname: Hu
authors.affiliation: Department of Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Kyung Sik
authors.initials: KS
authors.lastname: Kim
authors.affiliation: Department of Urology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Young Deuk
authors.initials: YD
authors.lastname: Choi
authors.affiliation: Department of Obstetrics and Gynecology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sunghoon
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Radiology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Young Han
authors.initials: YH
authors.lastname: Lee
authors.affiliation: Department of Radiology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Jin-Suck
authors.initials: JS
authors.lastname: Suh
authors.affiliation: Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, 134 Shinchondong, Seodaemun-gu, Seoul, 03722, Korea.
authors.forename: Joong Bae
authors.initials: JB
authors.lastname: Ahn
authors.affiliation: Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, 134 Shinchondong, Seodaemun-gu, Seoul, 03722, Korea.
authors.forename: Hyun Cheol
authors.initials: HC
authors.lastname: Chung
authors.affiliation: Department of Surgery, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Noh
authors.affiliation: Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, 134 Shinchondong, Seodaemun-gu, Seoul, 03722, Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Rha
authors.affiliation: Anatomic Pathology Reference Lab, Seegene Medical Foundation, Seoul, 05548, Korea. luhi7@naver.com.
authors.forename: Soo Hee
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Division of Medical Oncology, Department of Internal Medicine, Yonsei University College of Medicine, 134 Shinchondong, Seodaemun-gu, Seoul, 03722, Korea. hyosong77@yuhs.ac.
authors.forename: Hyo Song
authors.initials: HS
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D060890:B7-H1 Antigen / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007223:Infant; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012509:Sarcoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D012983:Soft Tissue Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D055815:Young Adult
chemical_list: D060890:B7-H1 Antigen; D014408:Biomarkers, Tumor; C423236:CD274 protein, human
keywords: Biomarker; PD-L1; Prognosis; Soft tissue sarcoma