RATIONALE: Drugs used in chemotherapy, such as fluorouracil and gemcitabine, work in different ways to stop tumor cells from dividing so they stop growing or die. Radiation therapy uses high-energy x-rays to damage tumor cells. Fluorouracil may make the tumor cells more sensitive to radiation therapy. Brachytherapy uses radioactive material, such as phosphorus P32, placed directly into or near a tumor to kill tumor cells. Combining chemotherapy and external-beam radiation therapy with brachytherapy may kill more tumor cells.