Pleural effusion (PE) occasionally develops in cancer patients during treatment with antibodies to programmed cell death-1 (PD-1) or to its ligand PD-L1 (hereafter, αPD-1 therapy).
The PD-L1 TPS was evaluated with 120 paired whole-tumor tissue sections and biopsy samples and with 70 paired biopsy and cytology samples (bronchial washes, n = 40; pleural effusions, n = 30).