DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed pancreatic adenocarcinoma

  • Locally advanced or metastatic disease by radiological evidence
• Must have biopsy material consisting of 10 unstained slides or paraffin-embedded tissue blocks available for correlative studies
• No endocrine tumor or lymphoma of the pancreas
• No history of CNS metastases

PATIENT CHARACTERISTICS:

• SWOG performance status 0-1
• Life expectancy ≥ 12 weeks
• Platelet count ≥ 100,000/mm^3
• Absolute neutrophil count ≥ 1,500/mm^3
• Bilirubin < 2.0 mg/dL
• AST and ALT < 1.5 times upper limit of normal
• Creatinine < 1.5 mg/dL
• Albumin > 2.5 g/dL
• INR < 1.3 (in the absence of ongoing treatment with warfarin)
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No active infection
• No condition that would limit the ability to receive oral medications
• No requirement for a gastrostomy tube for the administration of drugs
• No serious concurrent systemic disorder, that, in the opinion of the investigator, is incompatible with the study
• No active second primary malignancy within the past year except in situ carcinoma of the cervix or adequately treated basal cell carcinoma of the skin
• No allergy to any study drug

PRIOR CONCURRENT THERAPY:

• No prior chemotherapy or radiotherapy for metastatic disease

  • Prior adjuvant chemotherapy allowed provided it was completed at least 6 months ago
• No prior gemcitabine hydrochloride or epidermal growth factor receptor-inhibiting agents
• No other concurrent chemotherapy, immunotherapy, tumor-directed hormonal therapy, or radiotherapy
• No other concurrent investigational agents
• No other concurrent antitumor therapy