A Randomized Controlled Trial Evaluating of Prophylactic Irradiation in CRT for cT1bN0M0 ESCC

Inclusion criteria

• Histologically proven squamous cell carcinoma, adenosquamous carcinoma, or basaloid cell carcinoma.
• All lesions located in the thoracic esophagus. Secondary lesions with an absolute indication for endoscopic resection (EMR/ESD) may not be confined to the thoracic esophagus.
• Clinical N0M0 with cervical to abdominal contrast-enhanced CT.
• The deepest lesion is diagnosed as cT1b (SM1 / SM2 / SM3) with upper gastrointestinal endoscopy. If it is difficult to differentiate cT1a-MM and cT1b-SM1 clinically, the wall depth is diagnosed as cT1b-SM1.
• Aged 20 years and older.
• ECOG Performance status 0 or 1.
• No previous therapy against esophageal cancer except for complete resection by EMR/ESD with either pT1a-LPM (pM2) / pT1a-MM (M3) disease or pT1a-MM (M3) disease without vascular infiltration.
• No history of radiotherapy for the neck, chest, and upper abdomen for any cancers. No chemotherapy or hormone therapy with less than 3 years of disease-free interval for any cancers.
• Major organ function is preserved. 1) WBC<=12,000/mm3 2) ANC>=1,500/mm3 3) Hb>=10.0 g /dL 4) PLT>=10,000/mm3 5) T-bil<=1.5 mg /dL 6) AST<=100 IU/L 7) ALT<=100 IU/L 8) SpO2>=95% 9) Ccr>=60 mL/min
• Patients do not have a preference to receive a surgical resection as an initial therapy after receiving explanations.
• Written informed consent is obtained.

Exclusion criteria

• Simultaneous or metachronous (within 5 years) double cancers, except for intramucosal tumor curable with local therapy.
• Active infection requiring systemic therapy.
• Fever over 38 degrees Celsius
• Female during pregnancy, within 28 days of post parturition, or during lactation. Male who wants a partner's pregnancy.
• Psychological disorder, which is difficult to participate in this clinical study.
• Receiving continuous systemic corticosteroid or immunosuppressant treatment.
• Positive for HBs antigen or HIV antigen.
• Diabetes mellitus, which is uncontrollable with continuous use of insulin or hypoglycemic agents.
• Uncontrolled arterial hypertension.
• History of unstable angina pectoris within three weeks or myocardial infarction within six months before registration.
• Uncontrolled valvular disease, dilated cardiomyopathy, and hypertrophic cardiomyopathy.
• Severe emphysema, interstitial pneumonia or pulmonary fibrosis based on chest CT.
• With a history of cerebrovascular disorder within 6 months.
• Drug allergy for iodic drugs.