CD4 and non-small cell lung carcinoma: In this study, we examined the infiltrating level of TIL, CD4+TIL, and CD8+TIL in naïve and post‐chemotherapy NCT‐NSCLC tumor tissue specimens, and explored their prognostic value in patients with NCT‐NSCLC, both naïve and post‐chemotherapy tumor tissue specimens came from the same patients.