Aim: An epidemiological study was conducted based on an esophageal cancer patient’s cohort to investigate the association of folate intake and MTHFR C677T polymorphism with the prognosis of esophageal cancer

Esophageal cancer is the sixth most common cancer worldwide in 2002 (Blount et al., 2007). Its rates showed a wide international geographic variation in the incidence and mortality of esophageal cancer (Choi and Mason, 2000; Kim, 2004; Blount et al., 2007), suggesting that the role of genetic and environmental factors in the pathogenesis of this cancer (Choi and Mason, 2000). Possible risk factors for esophageal cancer include cigarette smoking, alchol drinking, hot-temperature food items, chronic mucosal irritation, and a family history of cancers (Wang et al., 2007; Falk, 2009; Morita et al., 2010). Deficiency of nutrients, such as folate, vitamin and trace elements, was also found to be associated with an increased risk for several cancers, including esophageal cancer, whereas a high intake of fruits and vegetables has been considered to be effective in prevention (Morita et al., 2010). Folate is a water-solution B vitamin, and folate deficiency can influence the carcinogenesis of esophageal cancer through two ways: one is inducing misincorportion of uracil into DNA to result in chromosomal breaks and mutations. Another is leading the alteration in DNA