Fig. 2From: Cytology cell blocks from malignant pleural effusion are good candidates for PD-L1 detection in advanced NSCLC compared with matched histology samplesImmunocytochemical double staining with antibodies against TTF-1 (red) and PD-L1 (brown) in MPE cell block section (magnification × 40). a Hematoxylin-eosin. b Double staining easily distinguishes difficult-to-identify tumor cells from nonneoplastic cellsBack to article page