CD4 and metastatic malignant neoplasm in the lymph nodes: This study aimed to investigate the densities of HIF-1α-expressing tumor cells, CD4+ T cells, and CD8+ T cells in the primary tumors of NSCLC patients, and to assess their associations with lymph node metastasis and postoperative recurrence.<h4>Methods</h4>256 formalin-fixed paraffin-embedded primary tumor specimens from NSCLC patients who underwent radical resection at Shandong First Medical University Affiliated Cancer Hospital between January 1, 2014 and December 31, 2018 were retrospectively collected.