Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed metastatic
adenocarcinoma of the colon or rectum that is not amenable to potentially curative therapy
(e.g., inoperable metastatic disease) At least 1 unidimensionally measurable lesion at
least 20 mm in diameter by conventional CT or MRI scan or at least 10 mm in diameter by
spiral CT scan Progressive disease by CT or MRI scan during or no more than 6 months after
the last dose of prior first-line irinotecan, fluorouracil, and leucovorin calcium (Saltz
regimen) 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) 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

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: See Disease
Characteristics One and only 1 prior chemotherapy regimen for metastatic disease
consisting of first-line irinotecan, fluorouracil, and leucovorin calcium (Saltz regimen)
Prior adjuvant fluorouracil with leucovorin calcium allowed At least 3 weeks since prior
chemotherapy for metastatic disease and recovered No prior adjuvant irinotecan No prior
oxaliplatin Endocrine therapy: Not specified Radiotherapy: No prior radiotherapy to study
lesions unless evidence of progressive disease within the radiotherapy port At least 3
weeks since prior radiotherapy Surgery: See Disease Characteristics At least 4 weeks since
prior major surgery and recovered Prior surgical resection of primary tumor or metastases
allowed Other: At least 30 days since prior investigational drugs No other concurrent
investigational agents No other concurrent anti-cancer therapy No concurrent participation
in other investigational trials