Gemcitabine and Erlotinib in Treating Patients With Metastatic or Recurrent Pancreatic Cancer

OUTLINE: This is a multicenter study. Patients receive gemcitabine hydrochloride IV on days 1, 8, and 15 and oral erlotinib hydrochloride on days 2-5, 9-12, and 16-26. Treatment repeats every 28 days for up to 1 year in the absence of disease progression or unacceptable toxicity. Archived tumor tissue samples are analyzed for the expression of EGFR, HER3, HER2, downstream signaling molecules, and other molecular markers by immunohistochemistry and RT-PCR. The presence of aberrant gene copy numbers (amplification and polysomy) for EGFR, HER3, and HER2 are determined by FISH. Blood samples are collected at baseline and periodically during study for polymorphism analysis and correlative molecular analysis of surrogate endpoint biomarkers. After completion of study therapy, patients are followed every 3 months.