Tumorigenesis and carcinogenesis are multifactorial and multistep processes. They deal with the transformations of normal cells into malignant cells. Carcinogenesis is ultimately the result of the exposure of the target epithelium in the esophagus to a carcinogenic agent. The carcinogenic molecule is almost certainly in gastric juice and delivered to the target cells by reflux of gastric contents into the esophagus. Journal of Carcinogenesis considers manuscripts in many areas of carcinogenesis and Chemoprevention. Primary areas of interest to the journal include: physical and chemical carcinogenesis and mutagenesis; processes influencing or modulating carcinogenesis, such as DNA repair; genetics, nutrition, and metabolism of carcinogens; and the mechanism of action of carcinogens.