Fig. 3From: Cytology cell blocks from malignant pleural effusion are good candidates for PD-L1 detection in advanced NSCLC compared with matched histology samplesDiscrepancy of tumor PD-L1 expression between immunohistochemical (IHC) single and double staining (magnification × 40). Single PD-L1 IHC staining (a, c) shows a higher tumor proportion score and stronger staining intensity compared with double IHC staining with anti-PD-L1 and TTF-1 (b, d) in both histology sample (a vs b) and MPE cell block (c vs d)Back to article page