All are Precancerous for carcinoma esophagus Except

.Aetiology of CARCINOMA OESOPHAGUS includes, *Diet, deficiencies (Vit. A, C, Riboflavin) *Mycotoxin *Alcohol and tobacco Common in men (Fungal contamination of food Common in China - Henan province) *Achalasia cardia In India, common in Oesophageal webs Orissa and Karnataka *Barrett's oesophagus *Plummer -Vinson's syndrome *Corrosive strictures *Tylosis *Nitrosamines Ref: SRB&;s manual of surgery,3 rd ed, pg no 751