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) AST and ALT no greater than 2 times ULN (no greater than 5 times ULN if liver metastases present) Alkaline phosphatase no greater than 2 times ULN (no greater than 3 times ULN if liver metastases present) Renal: Creatinine no greater than 1.5 times ULN Cardiovascular: No uncontrolled high blood pressure No unstable angina, symptomatic congestive heart failure, or serious cardiac arrhythmia No New York Heart Association class III or IV heart disease No history of cardiac toxicities with prior fluorouracil and leucovorin calcium No myocardial infarction within the past 6 months Pulmonary: No interstitial pneumonia or 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 dihydropyrimidine dehydrogenase deficiency No allergy to platinum-containing drugs No history of intolerance to study anti-emetics (e.g., 5-HT3 antagonists) No known peripheral neuropathy (absence of deep tendon reflexes as sole deficiency allowed) No uncontrolled diabetes No active infection No other active malignancy originating from primary site other than colon or rectum