LAUSR

e24294Background: Programmed cell death 1 ligand (PD-L1) expression and the tumour mutation burden (TMB) are distinct biomarkers of response to anti-PD-1/PD-L1 therapies. The proportion of PD-L1-positive, high-TMB patients and their overlap in newly diagnosed metastatic non-small cell lung cancer (NSCLC) and their effect on prognosis after receiving epidermal growth factor receptor (EGFR)-TKIs or platinum-based chemotherapy were evaluated. Methods: One hundred eighty-seven NSCLC patients were included. Tumour tissue samples were collected to detect PD-L1 expression and TMB status by immunohistochemistry (using the SP142 antibody) and targeting next-generation sequencing of specific genes, respectively. Correlations between PD-L1 or TMB with clinicopathological characteristics were analysed. Results: The PD-L1-positive rates of tumour cells were 37% (≥1%) and 20% (≥50%) in adenocarcinoma (ADC); 55% (≥1%) and 27% (≥50%) in squamous cell carcinoma (SQCC). PD-L1 in tumour cells was significantly associated wi...