<qa>  What is the name of the drug used in chemotherapy?RATIONALE: Drugs used in chemotherapy, such as 5-fluorouracil, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing and also as a radiosensibilisant. Radiation therapy uses high-energy x-rays to kill tumor cells. 5-fluorouracil may make tumor cells more sensitive to radiation therapy. Oral 5-fluorouracil is more convenient for ambulatory patients. Giving UFT Tegafur and Uracil with radiation therapy before surgery may shrink the tumor so it can be removed. 