1556O_PR - Analysis of expression of programmed cell death 1 ligand 1 (PD-L1) in malignant pleural mesothelioma (MPM)

Date 29 September 2014
Event ESMO 2014
Session SCLC and other thoracic malignancies
Topics Mesothelioma
Pathology/Molecular Biology
Translational Research
Presenter Susana Cedres
Citation Annals of Oncology (2014) 25 (5): 1-41. 10.1093/annonc/mdu438
Authors S. Cedres1, S. Ponce Aix2, J. Zugazagoitia2, A.B. Anguita3, I. Sansano4, A. Navarro Mendivil1, A. Martinez1, P. Martinez1, P. Fidalgo1, E. Felip1
  • 1Medical Oncology, Vall d`Hebron University Hospital Institut d'Oncologia, 08035 - Barcelona/ES
  • 2Servicio De Oncologia Medica, University Hosptial 12 De OctubreMedical oncology, ES-28041 - Madrid/ES
  • 3Servicio De Anatomia Patologica, University Hosptial 12 De OctubreMedical oncology, ES-28041 - Madrid/ES
  • 4Pathology Department, Vall d`Hebron University Hospital Institut d'Oncologia, 08035 - Barcelona/ES




The increasing incidence and poor outcome associated with MPM requires to find effective treatment for this disease. PD1/PD-L1 pathway plays a central role in tumor immune evasion and appears to be predictive and prognostic marker. PD-L1 is expressed in many different human cancers but its role in MPM has yet to be established. The aim of this study is to evaluate the expression of PD-L1 in MPM


119 MPM patients (p) from Vall d'Hebron University Hospital and 12 Octubre University Hospital between November 2002 and February 2014 were reviewed. Formalin-fixed, paraffin-embedded tissue was stained with anti-PD-L1 (clone E1L3N™) and intensity was scored as 0 (negative), 1 (weak), 2 (moderate) and 3 (strong). Cases showing more than 1% expression of PD-L1 were considered positive. Survival data were calculated by the Kaplan-Meier method. The associations of PD-L1 expression with outcome were assessed with Cox regression models.


Patient's characteristics: median age 69 years (42-90 years), males: 71.4%, PS 1:64.9%, asbestos exposure: 45%, stage III: 39%, epithelial subtype: 65.5%. PD-L1 was analyzed in 77 p and was positive in 20.7% p (14 samples in membrane, 16 in cytoplasm and 2 in immune infiltrate). PD-L1 intensity was weak in 56.2%, moderate in 25% and strong in 18.7% p. There was no significant relationship between PD-L1 expression and gender, smoking status, asbestos exposure, stage, and lymphocytic infiltration between PD-L1 positive and negative. We found differences in expression PD-L1 according to histology: PD-L1 expression was more frequent in no-epithelial tumor, 60% v 15% in epithelial; p = 0.033. The median survival in all population was 13.8 months, and for PD-L1 analysis patients, median survival in p PD-L1 positive was 4.79 vs 16.3 months in p PD-L1 negative (p = 0.012).


We have shown PD-L1 is expressed in 20% of p and is a prognostic marker in MPM. Our results suggest PD-L1 warrants further exploration in selecting p for immunotherapy


All authors have declared no conflicts of interest.