Chemotherapy and Internal Radiation in Treating Patients With Colorectal Cancer That Has Spread to the Liver

RATIONALE: Drugs used in chemotherapy work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Internal radiation uses radioactive material placed directly into or near a tumor to kill tumor cells. Giving chemotherapy together with internal radiation may kill more tumor cells.
PURPOSE: This phase II trial is studying how well giving chemotherapy together with internal radiation works in treating patients with colorectal cancer that has spread to the liver.