One hundred and twenty patients are divided into 3 groups and each group has 40 esophageal patients. Minimization stratified randomization will be applied. Oral anti-infective gargling agent, Mycostatin oral suspension, will be employed for one week before operation. The first groups will be treated without oral gargle agent; the second groups will be treated with gargling water; and the third groups will be treated with anti-infective gargling agent.