This a resource for (1) the collection of normal-appearing and neoplastic human esophageal tissue and cells at the time of surgery (cancer and non- cancer donors and of immediate autopsy (non-cancer donors) and (2) the culture and storage of esophageal epithelial and fibroblast cell stocks required to continue the carcinogenesis investigations of the Laboratory of Human Carcinogenesis. The contractor will provide the Laboratory with matched tumor and non-involved esophageal tissue and cell cultures from each human donor. These tissues and cells will be used to study malignant transformation caused by chemical, microbial and physical carcinogens and cocarcinogens. The tumorigenic potential of these cells will be further tested in athymic nude mice. Both of the latter objectives will be accomplished at the NCI laboratory.