Dual Epidermal Growth Factor Receptor Inhibition With Erlotinib and Panitumumab With or Without Chemotherapy for Advanced Colorectal Cancer

DISEASE CHARACTERISTICS:

* Histologically confirmed colorectal cancer

  * Metastatic disease

    * Biopsy of either the primary cancer or metastatic site required
  * Tumor expressing wild-type Kras mutations
* Progressive disease within 3 months after treatment with first-line fluorouracil (5-FU) and oxaliplatin-based chemotherapy OR evidence of metastatic disease within 6 months of completing adjuvant therapy with 5-FU and oxaliplatin
* Measurable disease defined as ≥ 1 lesion that can be accurately measured in ≥ 1 dimension (longest diameter to be recorded) as ≥ 20 mm with conventional techniques OR as ≥ 10 mm with spiral CT scan

PATIENT CHARACTERISTICS:

* ECOG performance status 0-2
* Life expectancy \> 6 months
* ANC \> 1,500/mm\^3
* Platelet count \> 100,000/mm\^3
* Hemoglobin ≥ 9 g/dL
* Creatinine \< 1.5 times upper limit of normal (ULN)
* Bilirubin \< 1.5 times ULN (or \< 2 mg/dL)
* AST and/or ALT \< 3 times ULN (\< 5 times ULN with liver metastases)
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception
* No concurrent malignancy requiring therapy except minor surgery for non-melanoma skin cancer removal
* No interstitial lung disease with symptoms (e.g., dyspnea or cough) including any of the following significant conditions:

  * Parenchymal lung disease
  * Metastatic disease
  * Pulmonary infections

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics
* No prior EGFR inhibitors, irinotecan hydrochloride, or other second-line chemotherapy regimens
* More than 4 weeks since prior radiotherapy
* No other concurrent investigational agents
* No other concurrent anticancer treatment modalities (e.g., radiotherapy)