PIK3CA and esophageal squamous cell carcinoma: Recent bioinformatics analysis using large amounts of short-read data from next-generation sequencing (NGS) has revealed genetic alterations in ESCC, including tumor protein 53 (TP53), cyclin-dependent kinase inhibitor 2A (CDKN2A), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), which are the major driver genes of ESCC12–15.