S-1, Cisplatin, and Radiation Therapy in Treating Patients With Stage IIA, Stage III, or Stage IVA Esophageal Cancer That Can Be Removed by Surgery

DISEASE CHARACTERISTICS: * Histologically confirmed carcinoma of the esophagus * Stage IIA-IVA disease * Resectable disease * Measurable disease, defined as at least 1 measurable lesion by RECIST criteria * No known brain metastasis PATIENT CHARACTERISTICS: * ECOG performance status 0-2 * Life expectancy \> 3 months * ANC ≥ 1,500/uL * Hemoglobin ≥ 9.0 g/dL (transfusion correction allowed) * Platelets ≥ 100,000/uL * Creatinine \< 1.5 mg/dL * Total bilirubin \< 2 times upper limit of normal (ULN) * ALT/AST \< 3 times ULN * Fertile patients must use effective contraception * Not pregnant or nursing * Able to take oral medication * No active peptic ulcer disease * No known hypersensitivity to study drugs * No serious uncontrolled systemic intercurrent illness, including the following: * Poorly controlled diabetes * Active infection * No history of significant neurological or mental disorder, including seizures or dementia * No malignancy within the past 5 years, except carcinoma in situ of the cervix, or nonmelanomatous carcinoma of the skin * No active cardiac disease uncontrolled by therapy * No myocardial infarction within the past 12 months * No interstitial lung disease or extended fibrosis of lung PRIOR CONCURRENT THERAPY: * No prior chemotherapy or radiotherapy for esophageal cancer * No prior surgical procedure affecting absorption * No concurrent flucytosine or other fluoropyrimidine-group anticancer drugs * No concurrent systemic chemotherapy, investigati…