Adverse Effects of Preserved Vegetables on ESCC and Precancer Lesions in a High Risk Area of China

Esophageal cancer (EC) is one of the common cancer in China, account for 16% cancer deaths (He et al., 2011). In 2008, more than half of new cases and deaths of EC worldwide happened in China (Ferlay et al., 2010), and esophageal squamous cell carcinoma (ESCC) was a predominantly pathological type (Lambert and Hainaut, 2007). National average incidence in males of 14.3/105 (He et al., 2011), and had a geographic variation in China (Zhang et al., 2006). Yanting County was one of the high risk areas for ESCC, with the incidence of nearly 5 times higher than the national average rate (Zhang et al., 2006; He et al., 2011; Song et al., 2012). The etiological factors of ESCC have not been documented clearly, and dietary factors were suspected to play an important role in the occurrence of the disease (Parkin et al., 2005). Preserved vegetable was a processed food and consumed particularly high in Yanting population. Processed food contained high level of N-nitroso compounds (Siddiqi et al., 1991). N-nitroso compounds had the potential carcinogenicity for ESCC