Based on this background, we retrospectively studied the clinical data of a cohort of advanced NSCLC patients who received anti-PD-1 immunotherapy and detected PCSK9 expression by immunohistochemistry (IHC) in baseline NSCLC tissues collected before treatment with ICIs, to identify whether PCSK9 expression in NSCLC tissues was associated with more or less response to anti-PD-1 immunotherapy. Here, PCSK9 is linked to non-small cell lung carcinoma.