This is an investigational study. Bevacizumab, oxaliplatin, and capecitabine are each FDA approved and commercially available for the treatment of some types of cancer, including colon and rectal cancer. They are not FDA approved for the treatment of small bowel or ampulla of Vater cancer. The use of the combination of oxaliplatin, capecitabine, and bevacizumab in patients with cancer of the small bowel or ampulla of Vater is investigational.