WOS
Permanent URI for this collectionhttps://hdl.handle.net/11443/932
Browse
1 results
Search Results
Item The importance of histological patterns on PD-L1 staining heterogeneity: Should we use pattern-based approach for selecting tumor samples for PD-L1 testing in lung(TUBITAK SCIENTIFIC \& TECHNICAL RESEARCH COUNCIL TURKEY, 2021-01-01) Bulutay, Pinar; Firat, Pinar; Zeren, Handan; Erus, Suat; Tanju, Serhan; Dilege, SukruBackground/aim: Programmed death ligand-1 (PD-L1) is a predictive marker for immunotherapeutic agents. However, heterogeneous staining of PD-L1 can cause false-negative results. The aim of this study is to evaluate the importance of histological patterns on PD-L1 staining heterogeneity in lung adenocarcinomas (LAC). Materials and methods: PD-L1 immunohistochemistry (IHC) stain was performed to two different tissue cores of 128 LAC cases, and cut-off values are given for grouping the cases according to the percentage of staining (1\%-10\%, 11\%-49\%, 50\%-100\%). Staining rates between cores were compared and analyzed by their histological patterns. Also, the relation of the PD-L1 expression with the clinicopathological characteristics of the cases was analyzed. Results: Overall, PD-L1 expression was observed in 53 of 128 cases (41.4\%, 1\% cut-off), 23.5\% of them were positive at 10\% cut-off and 14.1\% at 50\% cut-off. PD-L1 expression was significantly related to the high grade micropapillary and solid patterns of adenocarcinomas (p:0.01). Staining cut-offs were mostly similar between cores (43/50, 86\%) (k:0.843). However, 14\% of them were positive only in one core (7 of 50). This false negativity was mostly related to the histological patterns. Conclusion: Our data reveal the heterogeneous staining of PD-L1 expression, also micropapillary and solid patterns show higher rates of PDL expression. Therewithal, these findings also highlight the importance of taking into consideration of histological patterns, when choosing a paraffin block for the PDL1.