A system for treating abnormal mucosa in an esophagus comprises an access catheter, an energy delivery structure near a distal end of the access catheter, and a power supply for delivering energy through the energy delivery structure under conditions which injure or ablate the mucosal layer of the esophageal wall without causing substantial injury or heating of the submucosal layer. By injuring or necrosing metaplastic or other abnormal mucosal cells, regrowth of the mucosa substantially free from abnormal cells can be initiated.
