Bevacizumab, Capecitabine, and Oxaliplatin in Treating Advanced Small Intestinal or Ampulla of Vater Adenocarcinoma

Inclusion Criteria: * Patients must have histologically confirmed adenocarcinoma of the small bowel or ampulla of Vater * Prior adjuvant chemotherapy (including fluorouracil \[5-FU\], capecitabine, and oxaliplatin) for the treatment of adenocarcinoma of the small bowel or ampulla of Vater is allowed if completed \>= 52 weeks prior to first dose of study treatment * Prior capecitabine or 5-FU administered as a radio-sensitizing agent concurrently with external beam radiotherapy is allowed * Patients must have metastatic disease * A minimum of 4 weeks must have elapsed from completion of any prior chemotherapy or radiotherapy or surgery and the start date of study therapy * Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2 * Absolute neutrophil count (ANC) \>= 1,500/ul * Platelets \>= 100,000/ul * Total bilirubin =\< 1.5 x upper limit of normal (ULN) * In patients with known Gilbert's syndrome direct bilirubin =\< 1.5 x ULN will be used as organ function criteria, instead of total bilirubin * Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase \[SGOT\]) and alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase \[SGPT\]) \< 3 x ULN * Calculated creatinine clearance (CrCl) \> 50 cc/min (calculated using the Cockcroft and Gault formula) * Negative serum or urine pregnancy test in women with childbearing potential (defined as not post-menopausal for 12 months or no previous surgical sterilization), within one week prior…