Eighty five per cent of cancers arise in the middle third of the oesophagus, with the rest evenly distributed between the upper third and the lower third. The overwhelming majority of the cancers in the upper two thirds are squamous carcinomas (as expectred as the lining of the oesophagus is squamous cells), whereas a quarter of those arising in the lower third are adenocarcinomas, suggesting an origin from glands – perhaps from gastric glands.
