Its amplification results in EGFR—independent activation of numerous signaling pathways, which are physiologically activated by EGFR in the context of NSCLC (mitogen-activated protein kinase—MAPK, signal transduction and activator of transcription—STAT, phosphatidylinositol 3-kinase—PI3K–Akt). This evidence concerns the gene PIK3CA and non-small cell lung carcinoma.