Cox regression was used to analyze the relationship between OS and clinicopathological characteristics including gender, age, T classification, N classification, body mass index (BMI), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), serum CD4+T lymphocytes, serum CD8+T lymphocytes, carcinoembryonic antigens CA19-9, CA72-4, CA125, tumor location, histological type, neural invasion, and vascular invasion (Table 2). This evidence concerns the gene CD8A and neoplasm.