CD274 and neoplasm: The benefit of pembrolizumab correlated with PD-L1 expression levels, with greater efficacy in patients with a tumour proportion score (TPS) \documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\ge$$\end{document}≥ 50%.