OBJECTIVES:~Primary~To determine the maximum tolerated dose and the recommended phase II dose of erlotinib hydrochloride in combination with gemcitabine hydrochloride and oxaliplatin in patients with advanced biliary tract cancer, pancreatic cancer, duodenal cancer, or ampullary cancer.~Secondary~To describe any antitumor activity associated with this treatment regimen when given during the dose-escalation and expanded-cohort portions of this study.~To evaluate e-cadherin, vimentin, fibronectin, amphiregulin, and Kras status in the tumors and assess their relationship to response.~OUTLINE: This is a multicenter, dose-escalation study of erlotinib hydrochloride.~Patients receive gemcitabine hydrochloride IV on day 1, oxaliplatin IV over 2 hours on day 2, and oral erlotinib hydrochloride once daily on days 3-8. Courses repeat every 2 weeks in the absence of disease progression or unacceptable toxicity.~Tumor tissue samples are collected for biomarker and other analysis.~After completion of study treatment, patients are followed up for 30 days.
RATIONALE: Drugs used in chemotherapy, such as gemcitabine hydrochloride and oxaliplatin, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Erlotinib hydrochloride may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Giving gemcitabine hydrochloride and oxaliplatin together with erlotinib hydrochloride may kill more tumor cells.~PURPOSE: This phase I trial is studying the side effects and best dose of erlotinib hydrochloride when given together with gemcitabine hydrochloride and oxaliplatin in treating patients with advanced biliary tract cancer, pancreatic cancer, duodenal cancer, or ampullary cancer.