RATIONALE: Monoclonal antibodies, such as cetuximab and trastuzumab, can block tumor growth
in different ways. Some block the ability of tumor cells to grow and spread. Others find
tumor cells and help kill them or carry tumor-killing substances to them. Giving cetuximab
together with trastuzumab may kill more tumor cells.
PURPOSE: This phase I/II trial is studying the side effects and best dose of trastuzumab when
given together with cetuximab and to see how well it works in treating patients with
metastatic pancreatic cancer that progressed after previous treatment with gemcitabine.