INTRODUCTIONTo date,the major therapy for rectal carcinoma isextensive abdomino-perineal resection.Unfortunately,after resection of rectal carcinoma,many patients still die of blood-borne metastases,usually in the liver or lungs,or local pelvicrecurrence,which is the major cause ofmorbidity and mortality in patients with rectalcarcinoma.Pre-or postoperative radiotherapy canreduce the incidence of local recurrence,buteven with moderately high radiation doses,manypatients are not locally controlled and have distantmetastases.The reason for this may be low INTRODUCTIONTo date,the major therapy for rectal carcinoma isextensive abdomino-perineal resection.Unfortunately,after resection of rectal carcinoma,many patients still die of blood-borne metastases,usually in the liver or lungs,or local pelvicrecurrence,which is the major cause of morbidity And mortality in patients with rectalcarcinoma.Pre-or postoperative radiotherapy canreduce the incidence of local recurrence, buteven with moderately high radiation doses,manypatients are not locally controlled and have distantmetastases.The reason for this may be low