PATIENT CHARACTERISTICS: Age: 18 to 70 Performance status: WHO 0-2 Life expectancy: More than 6 months Hematopoietic: WBC greater than 4,000/mm3 Platelet count greater than 100,000/mm3 Neutrophil count greater than 1,500/mm3 Hemoglobin greater than 10 g/dL Hepatic: Not specified Renal: Creatinine less than 1.5 mg/dL Other: Not pregnant Fertile patients must use effective contraception during and for 2 months after study No other prior malignancy except nonmelanomatous skin cancer or carcinoma in situ of the cervix No prior serious illness of the gastrointestinal tract (e.g., rectal bleeding or diverticulosis with complications) No contraindication to fluorouracil, cisplatin, or radiotherapy