Lapatinib Ditosylate and Capecitabine in Treating Patients With Metastatic Pancreatic Cancer

RATIONALE: Lapatinib ditosylate may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Drugs used in chemotherapy, such as capecitabine, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Giving lapatinib ditosylate together with capecitabine may kill more tumor cells. PURPOSE: This phase II trial is studying how well giving lapatinib ditosylate together with capecitabine works in treating patients with metastatic pancreatic cancer.