Radiation Therapy, Surgery, and Chemotherapy in Treating Patients With Rectal Cancer That Can Be Surgically Removed

DISEASE CHARACTERISTICS: * Histologically confirmed resectable adenocarcinoma of the rectum * Any grade * Tumor macroscopically within 15 cm of anal margin on rigid rectoscopy * Tumor tethered or partially fixed on digital rectal exam and/or T3-4 on rectal ultrasound * No acute or subacute bowel obstruction without colostomy diversion * No chronic inflammatory disease of the ileum and/or colon * No primary adenocarcinoma of the anal canal * No distant metastasis PATIENT CHARACTERISTICS: Age: * 80 and under Performance status: * WHO 0-1 Life expectancy: * Not specified Hematopoietic: * Granulocyte count greater than 2,000/mm\^3 * Platelet count greater than 130,000/mm\^3 Hepatic: * Not specified Renal: * Creatinine less than 1.36 mg/dL Cardiovascular: * No angina pectoris Other: * No other prior malignancy except basal cell skin cancer or carcinoma in situ of the uterine cervix PRIOR CONCURRENT THERAPY: Biologic therapy * No prior biologic therapy for adenocarcinoma of the rectum Chemotherapy * No prior chemotherapy for adenocarcinoma of the rectum Endocrine therapy * No prior endocrine therapy for adenocarcinoma of the rectum Radiotherapy * No prior radiotherapy for adenocarcinoma of the rectum Surgery * No prior surgery for adenocarcinoma of the rectum