KRT19 and non-small cell lung carcinoma: First, it should be noted that this study has only examined a small sample size and is a single-center study—research should be done on a large scale and using multicenter prospective validation of NSCLC groups; second, we only focused on the impact of preoperative serum albumin (ALB), ALT, AST, NLR, and PLR on the prognosis of patients with NSCLC, but other traditional prognostic factors, such as cytokeratin 19 fragment (CYFRA21-1) [23], carcinoembryonic antigen (CEA) [24], SCC antigen [24], and cancer antigen 125 (CA 125) [25], were not available in this study.