Pd l1 clone 22c3 pharmdx kit

We consecutively collected 54 patients with pathologically confirmed adenocarcinoma of lung and activating EGFR mutation at diagnosis between January 2016 and December 2017 from Seoul St. Mary’s Hospital, Incheon St. Mary’s Hospital, Bucheon St. Mary’s Hospital, St. Paul’s Hospital, and Uijeongbu St. Mary’s Hospital, Korea. Based on pack-year (PY) defined as average number of cigarettes per day/20× years of smoking, patients were categorized as never smokers (<100 cigarettes in their life-time), light smokers (0< PY <30), or heavy smokers (PY ≥30). Genotying of EGFR was done using peptide nucleic acid (PNA)-mediated PCR clamping method such as PNAClamp TM EGFR Mutation Detection Kit (PANAGENE, Inc., Daejeon, Korea) using real-time PCR. Activating EGFR mutation was defined as exon 19 deletion or exon 21 point mutation. PD-L1 immunohistochemistry testing was performing using PD-L1 clone 22C3 pharmDx kit and Dako automated Link 48 platform (Dako, Carpenteria, CA, USA). PD-L1 tumor proportion score (TPS) was calculated as the percentage of at least 100 viable tumor cells with complete or partial membrane staining.

All viable cancer cells on the entire pathologic tissue section were evaluated and included in the PD-L1 scoring analysis.
Programmed death-ligand 1 IHC testing was performed using the PD-L1 clone 22C3 pharmDx kit and Dako Automated Link 48 platform (Agilent Technologies/Dako, Carpinteria, CA, USA). The PD-L1 tumor proportion score (TPS) was calculated as the percentage of the at least 100 viable cancer cells with complete or partial membrane staining. Necrotic areas were excluded from scoring. Each patient sample was separated into 3 groups with <1% (no expression), 1% to 49% (low expression), or ⩾50% (high expression) positive tumor cells. Programmed death-ligand 1 expression positivity is defined as low and high expression on the basis of the clinical trial assay that may maximally predict the clinical response of patients with NSCLC treated with pembrolizumab.^{1 (link)}