This study is being done to see if treatment for esophageal cancer can be done using endoscopy for patients ineligible for surgical or radiological therapy. The standard method of treating this type of cancer is surgical removal of the esophagus. The study will determine if removing just the cancer with endoscopy is enough treatment or if the addition of another treatment called photodynamic therapy (treatment with a red light and a drug called sodium porfimer) is needed.