We aimed to determine the link between the bacterial compositions of NSCLC patients along the gut–lung axis in relation to clinical parameters, molecula r markers of systemic inflammation such as CRP (C-reactive protein), the NLR (neutrophil-to-lymphocyte ratio), LPS (lipopolysaccharide), CD8+ cells (cytotoxic T lymphocytes), and the expression levels of PD-L1 protein (Figure 1). Here, CRP is linked to non-small cell lung carcinoma.