Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed recurrent metastatic
adenocarcinoma of the colon or rectum Not amenable to potentially curative treatment
(e.g., inoperable metastatic disease) Must have received 2, and only 2, prior chemotherapy
regimens for metastatic or recurrent disease, including the following: First-line therapy
with bolus or continuous infusion fluorouracil (5-FU) (with or without leucovorin calcium)
or capecitabine OR Adjuvant therapy with 5-FU and leucovorin calcium after relapse during
or within 6 months of completion of first-line therapy Second-line therapy with irinotecan
or after adjuvant 5-FU and leucovorin calcium treatment failure Progressive disease by CT
scan or MRI during or after first-line treatment as above OR during or within 6 months of
completion of adjuvant chemotherapy as above AND during second-line irinotecan or after
adjuvant treatment failure as above At least 1 unidimensionally measurable lesion At least
20 mm by CT scan or MRI At least 10 mm by spiral CT scan

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 liver
metastases present) Alkaline phosphatase no greater than 2 times ULN (6 times ULN if liver
metastases present) Renal: Creatinine no greater than 1.5 times ULN Cardiovascular: No
unstable angina No myocardial infarction within the past 6 months No New York Heart
Association class III or IV symptomatic congestive heart failure No serious cardiac
arrhythmia Pulmonary: No interstitial pneumonia or extensive and symptomatic fibrosis of
the lung Other: No history of intolerance to antiemetics (e.g., 5-HT3 antagonists) or
antidiarrheal medication (e.g., loperamide) to be administered concurrently with study
chemotherapy No history of allergies to drugs containing platinum No known concurrent
peripheral neuropathy No diabetes No active infection Not pregnant or nursing Negative
pregnancy test Fertile patients must use effective contraception during and for 6 months
after study No other active cancer from another primary site except surgically treated
non-melanoma skin cancer, carcinoma in situ of the cervix, or localized prostate cancer
with an undetectable PSA level

PRIOR CONCURRENT THERAPY: Biologic therapy: No prior biologic therapy Chemotherapy: See
Disease Characteristics At least 3 weeks since prior chemotherapy, including irinotecan,
for metastatic or recurrent disease and recovered No other prior first-line chemotherapy
agents for metastatic or recurrent disease No prior adjuvant irinotecan No prior
oxaliplatin Endocrine therapy: Not specified Radiotherapy: At least 3 weeks since prior
radiotherapy No prior radiotherapy to target lesions unless documented disease progression
within the radiation portal Surgery: See Disease Characteristics More than 4 weeks since
prior surgery for primary or metastatic disease and recovered Other: No prior
investigational anticancer drug administered with irinotecan No other concurrent
investigational drugs