20.500.12556/DiRROS-13805 Prognostic impact of PD-1 and PD-L1 expression in malignant pleural mesothelioma : an international multicenter study Background: Programmed cell death 1/programmed death ligand 1 (PD-1/PD-L1) immune-checkpoint blockade is a promising new therapeutic strategy in cancer. However, expression patterns and prognostic significance of PD-L1 and PD-1 are still controversial in human malignant pleural mesothelioma (MPM). Methods: Formalin-fixed paraffin-embedded (FFPE) tumor samples from 203 MPM patients receiving standard treatment without immunotherapy were collected from 5 European centers. PD-L1 and PD-1 expression of tumor cells (TCs) and tumor-infiltrating lymphocytes (TILs) were measured by immunohistochemistry and correlated with clinical parameters and long-term outcome. Results: High (>10%) PD-L1 TC and PD-1 TILs expressions were found in 18 (8%) and 39 (24%) patients, respectively. PD-L1 was rarely expressed by TILs [>/=1%, n=13 (8%); >10%, n=1]. No significant associations were found between the PD-L1 or PD-1 expression of TCs or TILs and clinicopathological parameters such as stage or histological subtype. Notably, patients with high (>10%) TC-specific PD-L1 expression exhibited significantly worse median overall survival (OS) (6.3 vs. 15.1 months of those with low TC PD-L1 expression; HR: 2.51, P<0.001). In multivariate cox regression analysis adjusted for clinical parameters, high TC PD-L1 expression (>10%) proved to be an independent negative prognostic factor for OS (HR: 2.486, P=0.005). There was no significant correlation between PD-L1 or PD-1 expression of TILs and OS. Conclusions: In this multicenter cohort study, we demonstrate that high (>10%) PD-L1 expression of TCs independently predicts worse OS in MPM. Further studies are warranted to investigate the value of PD-L1/PD-1 expression as a marker for treatment response in MPM patients receiving immunotherapy. mesothelioma - anatomy and histology - analysis 1malignant pleural mesothelioma programmed death-ligand 1 programmed cell death 1 PD-L1 mezoteliom - anatomija in histologija - analiza maligni plevralni mezoteliom ligand programirane celične smrti 1 programirana celična smrt 1 PD-L1 true false true AME Publishing Angleški jezik Ni določen © Translational Lung Cancer Research Neznano 2021-03-31 14:34:03 2021-03-31 14:34:04 2022-08-19 03:36:50 0000-00-00 00:00:00 2021 0 Kitajska 0 Nasl. z nasl. zaslona; Soavtorji iz Slovenije: Tanja Cufer, Ales Rozman, Izidor Kern, Katja Mohorcic; Opis vira z dne 22. 3. 2021; str. 1-14 no. Vol. 10 2021 0000-00-00 PostprintKoncna VTisku NiDoloceno 0000-00-00 0000-00-00 0000-00-00 616-006 2226-4477 10.21037/tlcr-20-1114 56719619 https://tlcr.amegroups.com/issue/publishAheadOfPrint 1 https://dirros.openscience.si/Dokument.php?lang=slv&id=16906 Univerzitetna klinika za pljučne bolezni in alergijo Golnik 0 0 0