ESR1 and carcinoma of esophagus: Although we are some considerable way off from understanding the apparent paradox of increased ER expression in oesophageal cancer and a seemingly better prognosis in women, a concerted research effort is required in order to determine relative levels of ERα:ERβ according to gender and age, ER expression patterns with disease progression, modulation of oestrogen production and the role of environmental and phytooestrogens, by immunochemical, molecular and functional assays.