Role of Esophagectomy in Complete Responders to CCRT

Inclusion Criteria: 1. Histologically proven squamous cell carcinoma of the intrathoracic esophagus 2. Surgically resectable (cT3, cT4a and/or disease with lymph node metastasis by AJCC 7th ed) esophageal cancer, as determined by Endoscopic Ultra Sound (EUS), chest CT and PET-CT 3. No prior treatment for the esophageal cancer 4. Age: 20-70 years 5. ECOG performance status 0, 1 or 2 6. Adequate hematological, renal, hepatic, pulmonary and cardiac functions defined as 6.1 Granulocytes \> 1,500/microliter, Platelets \> 75,000/microliter 6.2 Creatinine \< 1.5 mg/dL (or CCr\> 50 mg/mL), 6.3 Total bilirubin \< 1.5 mg/dL 6.4 ALT and AST \< 2.5 × upper normal limit 6.5 FEV1 \>=1.5 L/min 6.6 Ejection fraction \>= 45% 7. Non-pregnant, non-lactating female patients. Sexually active patients of childbearing potential must implement effective contraceptive practices during the study when treated with chemotherapy 8. Written, voluntary informed consent Exclusion Criteria: 1. Subtypes other than squamous cell carcinoma 2. cT1N0M0, cT2N0M0 esophageal cancer or in situ carcinoma 3. Invasion of recurrent laryngeal, phrenic or sympathetic nerve 4. Invasion of the tracheobronchial tree or presence of tracheoesophageal fistula 5. Invasion of major vessels (vena cava, azygos vein and aorta) by the tumor 6. Malignant pleural effusion (documented by cytospin or cytology) 7. Cervical esophageal cancer 8. Para-aortic lymph node metastasis 9. Past or current history of malignancy other than entry diagnosis except for non-melanomatous skin cancer, curatively treated carcinoma in situ of the cervix, curatively treated early gastric cancer with endoscopic mucosal resection or a cured malignancy more than 5 years prior to enrollment 10. Previous chemotherapy or prior history of radiotherapy interfering with the planned radiotherapy as per protocol 11. Patients with a known history of HIV seropositivity or HCV (+). Patients with HBV (+) are eligible. However, primary prophylaxis using antiviral agents (i.e. lamivudine, etc) is recommended for HBV carrier to prevent HBV reactivation during whole treatment period. 12. Other serious illness or medical conditions A. Unstable cardiac disease (i.e. congestive heart failure, arrhythmia, symptomatic coronary artery disease) despite treatment, myocardial infarction within 6 months prior to study entry B. History of significant neurologic or psychiatric disorders including dementia or seizures C. Active uncontrolled infection (viral, bacterial or fungal infection) D. Other serious medical illnesses 13. New York heart Association Class III/IV and history of active angina. Documented myocardial infarction within the 6 months preceding registration. Patients with a history of significant ventricular arrhythmia requiring medication or congestive heart failure. History of 2nd or 3rd degree heart blocks. 14. Active infection or other serious underlying medical condition which would impair the ability of the patient to receive the planned treatment 15. Dementia or altered mental status that would prohibit the understanding and giving of informed consent 16. Uncontrolled diabetes mellitus: fasting glucose \>150 mg/dL or patients requiring insulin therapy for glycemic control; fasting glucose \>150 mg/dL or patients requiring insulin therapy for glycemic control;