This study was carried out to explore the relationship between gene expression levels of immune-related genes (i.e., PD-1, PD-L1, PD-L2, IDO-1, IDO-2 and INFγ) assessed by quantitative-PCR arrays and their association with prognosis on a series of resected NSCLC patients. This evidence concerns the gene IDO1 and non-small cell lung carcinoma.