Clinical Significance Of Pd-L1 Expression And Cd8-Positive Tumor-Infiltrating Lymphocytes In Patients With Cavitary Lung Adenocarcinoma

Cavitary lung cancer is a rare type of lung cancer. Generally, the relationship between cavitary lung adenocarcinoma (LUAD) and specific immune checkpoints remains unknown. In this study, we aimed to detect the expression of programmed cell death ligand-1(PD-L1) and the density of CD8-positive (CD8(+)) tumor-infiltrating lymphocytes (TILs) to evaluate their clinicopathological significance in the case of patients with cavitary LUAD. This study included 65 patients with cavitary LUAD. Patient specimens were obtained from surgery. The expression of PD-L1 protein and CD8(+) TIL status was detected by traditional immunohistochemistry and multiplex quantitative immunofluorescence technology. The correlation of PD-L1 expression and CD8(+) TIL status was assessed along with clinicopathological parameters. This included evaluation of overall survival in cavitary LUAD patients based on the follow-up data. High expression of PD-L1 protein was detected in the cancerous tissues of cavitary LUAD patients, whose positive rate was recorded at 44.6% (29/65). PD-L1 expression level was significantly related with the lymph node (P = 0.001), TNM stage (P = 0.024), and CD8(+) TIL status (rs = -0.272, P = 0.025). High PD-L1 expression indicated high mortality rate (P < 0.001); however, the CD8(+) TIL group showed better survival in cavitary LUAD patients (P = 0.011). This phenotype, with high PD-L1 expression and low CD8(+) TILs, can predict poorer overall survival of patients with cavitary LUAD compared with the other phenotypes. Moreover, CD8(+) TIL level was an independent good prognosis factor. Initially, we reported that PD- L1 is upregulated in cavitary LUAD patients and that high expression of PD-L1 negatively correlates with CD8(+) TIL status. High PD-L1 expression and low CD8(+) TILs can predict decreased overall survival of patients with cavitary LUAD.