TP53 and esophageal squamous cell carcinoma: Further studies are needed to analyze in detail the mechanisms causing the extremely high load of TP53 mutation observed in ESCC cases from Golestan and to assess whether similar mechanisms may characterize ESCC carcinogenesis throughout the so-called “Central Asian Esophageal Cancer Belt”, an area encompassing several populations and extending from the Caspian Sea to the Sea of China in which ESCC is the most frequent type of cancer.