Cryotherapy ablation destroys the abnormal lining of the esophagus by exposing cells to extreme cold using liquid nitrogen. It is a new technique which is done during an EGD (upper endoscopy). Candidates for cryotherapy ablation are patients who have: A) Barrett’s esophagus with high-grade dysplasia or B) early stage esophageal cancer not amenable to standard therapies including surgery, chemotherapy, and radiation.