Around 40% oncogenic aberrations occurring in genes such as KIT, PIK3CA, MTOR, and NFE2L2 were heterogeneously distributed in sub-clones of ESCC patient tumor tissues, while genetic alterations in TP53, ZNF750, and MLL2 occur during earlier stages and are more predominant 38. This evidence concerns the gene PIK3CA and esophageal squamous cell carcinoma.