Chemotherapy With or Without Surgery in Treating Patients With Metastatic Colorectal Cancer That Cannot Be Removed by Surgery

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. Giving chemotherapy after surgery may kill any tumor cells that remain after surgery. It is not yet known whether chemotherapy is more effective when given alone or together with surgery in treating patients with colorectal cancer. PURPOSE: This randomized phase II/III trial is studying how well chemotherapy works and compares it with surgery followed by chemotherapy in treating patients with metastatic colorectal cancer that can not be removed by surgery.