Fluorouracil and Leucovorin With or Without Oxaliplatin in Treating Patients With Recurrent Metastatic Colorectal Cancer

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed adenocarcinoma of the colon or rectum Metastatic/recurrent disease not amenable to potentially curative therapy (e.g., inoperable metastatic disease) Documented sequential disease progression (by CT scan or MRI) after 2 prior chemotherapy regimens for metastatic/recurrent disease At least 1 unidimensionally measurable lesion At least 20 mm by conventional CT scan or MRI OR At least 10 mm by spiral CT scan Must have received prior fluorouracil (or capecitabine) and leucovorin calcium with or without irinotecan as first-line therapy and irinotecan with or without fluorouracil (or capecitabine) and leucovorin calcium as second-line therapy for metastatic disease PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 50-100% Life expectancy: Not specified Hematopoietic: Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin no greater than 1.5 times upper limit of normal (ULN) SGOT and SGPT no greater than 2 times ULN (6 times ULN if documented liver metastases present) Alkaline phosphatase no greater than 2 times ULN (6 times ULN if documented liver metastases present) Renal: Creatinine no greater than 1.5 times ULN Cardiovascular: No New York Heart Association class III or IV symptomatic congestive heart failure No serious cardiac arrhythmia No unstable angina No myocardial infarction within the past 6 months Pulmonary: No interstitial pneumonia No extensive and symptomatic fibrosis of the lung Other: Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for 6 months after study No known peripheral neuropathy (absence of deep tendon reflexes as the sole neurologic abnormality allowed) No diabetes or active infection No known dihydropyrimidine dehydrogenase deficiency PRIOR CONCURRENT THERAPY: Biologic therapy: No prior anticancer biologic therapy Chemotherapy: See Disease Characteristics No prior oxaliplatin No prior adjuvant irinotecan Prior adjuvant fluorouracil and leucovorin calcium allowed At least 3 weeks since prior chemotherapy (e.g., second-line irinotecan with or without fluorouracil (or capecitabine) and leucovorin calcium) for metastatic disease and recovered Endocrine therapy: Not specified Radiotherapy: At least 3 weeks since prior radiotherapy No prior radiotherapy to target lesion unless documented progression within the radiation portal Surgery: See Disease Characteristics At least 4 weeks since prior surgery for primary tumor or metastases and recovered Other: No prior investigational anticancer drug No other concurrent investigational agents