Surgery With or Without Radiofrequency Ablation Followed by Irinotecan in Treating Patients With Colorectal Cancer That is Metastatic to the Liver

DISEASE CHARACTERISTICS:

* Histologically confirmed primary colorectal adenocarcinoma
* Hepatic metastases that are considered completely resectable

  * No more than 4 metastases by dual phase CT scan OR
* Hepatic metastases that are not completely resectable but are amenable to complete destruction with resection and radiofrequency ablation

  * More than 4 metastases allowed if all disease can be resected or destroyed in situ with radiofrequency ablation
* No extrahepatic disease in any location
* No recurrent or second primary colorectal cancer by colonoscopy within the past year
* Received prior adjuvant chemotherapy with a fluorouracil-based regimen with the last dose at least 1 month prior to surgery
* No prior radiofrequency ablation with residual viable intrahepatic disease by CT scan
* No plans to be treated with radiofrequency ablation alone without surgical resection

PATIENT CHARACTERISTICS:

Age:

* 18 and over

Performance status:

* ECOG 0-1

Life expectancy:

* Not specified

Hematopoietic:

* Absolute neutrophil count at least 1,500/mm\^3
* Platelet count at least 100,000/mm\^3

Hepatic:

* Bilirubin no greater than 1.5 times upper limit of normal (ULN)
* AST and ALT no greater than 5 times ULN
* No Gilbert's disease or other known defect in hepatic conjugation or glucuronidation

Renal:

* Creatinine no greater than 1.5 times ULN

Cardiovascular:

* No myocardial infarction within the past 6 months
* No congestive heart failure requiring therapy

Other:

* Not pregnant or nursing
* Fertile patients must use effective contraception during and for 30 days after study
* No other malignancy within the past 5 years except inactive non-melanoma skin cancer or carcinoma in situ of the cervix
* No active serious infection
* No other serious underlying medical condition or severe concurrent disease that would preclude study participation
* No dementia, significantly altered mental status, or psychiatric illness that would preclude study participation
* No known hypersensitivity to irinotecan
* No known infection with HIV or AIDS
* No uncontrolled diabetes mellitus
* No history of seizures
* No drug or alcohol abuse within the past year

PRIOR CONCURRENT THERAPY:

Biologic therapy:

* Not specified

Chemotherapy:

* See Disease Characteristics
* No prior irinotecan

Endocrine therapy:

* Not specified

Radiotherapy:

* No prior radiotherapy to more than 30% of bone marrow
* No prior radiotherapy to the liver
* At least 3 months since prior radiotherapy to the pelvis or other areas

Surgery:

* See Disease Characteristics
* No prior resection of hepatic metastases (wedge biopsy allowed)

Other:

* No concurrent phenytoin, phenobarbital, or other antiepileptic medication
* No concurrent enrollment in other investigational drug trials