Inclusion Criteria:

• Histologically or cytologically documented recurrent, metastatic or unresectable gastroesophageal (Siewert type I, II, III) or gastric adenocarcinoma with measurable or assessable non-measurable disease (RECIST criteria).
• If recurrent or metastatic disease is not histologically confirmed, then documentation by a second radiographic procedure (i.e., PET scan or MRI in addition to CT scan) is required. If the imaging procedure does not confirm recurrent or metastatic disease, biopsy confirmation is required
• 12 months since completion of any prior neoadjuvant or adjuvant therapy (chemotherapy or radiotherapy) for potentially resectable gastroesophageal or gastric adenocarcinoma.
• >4 weeks since major surgery.
• ECOG Performance Status: 0-1
• Life expectancy >12 weeks
• Laboratory parameters as follows: absolute neutrophil count ≥1,500/uL, platelet count ≥100,000/uL, hemoglobin ≥9 g,/dL, creatinine <1.5 X ULN or estimated GFR >30 ml's/min, urinalysis <2+ protein, baseline proteinuria <1000 mg/d or urine protein/creatinine ratio <1, bilirubin <2 X ULN, PT (INR) <1.5 if patient not on anticoagulation, negative pregnancy test in women of childbearing age
• Hypertension must be well controlled (<160/90)
• Paraffin block or slides must be available
• Patients on full-dose anticoagulants must be on a stable dose of warfarin and have an in-range INR or be on a stable dose of low molecular weight heparin.

Exclusion Criteria:

• prior treatment for recurrent, metastatic, or unresectable gastroesophageal or gastric adenocarcinoma
• other concurrent anticancer therapy
• other malignancy within past three years except basal cell carcinoma of the skin, cervical carcinoma in situ, or nonmetastatic prostate cancer known central nervous system metastases or carcinomatous meningitis.
• interstitial pneumonia or extensive and symptomatic interstitial fibrosis of the lung.
• > grade 2 sensory peripheral neuropathy.
• uncontrolled seizure disorder, active neurological disease, or known CNS disease.
• significant cardiac disease, including the following: unstable angina, New York Heart Association class II-IV congestive heart failure, myocardial infarction within six months prior to study enrollment.
• history of hypertensive crisis or hypertensive encephalopathy
• abdominal fistula, gastrointestinal bleeding, or intra-abdominal abscess within the 6 months prior to study enrollment.
• core biopsy or other minor surgical procedure, excluding placement of a vascular access device, within 7 days prior to study enrollment.
• major surgical procedure, open biopsy, or significant traumatic injury within 28 days prior to study enrollment or anticipation of need for major surgical procedure during the course of the study.
• recent arterial thrombotic events including stroke or TIA within 6 months prior to study enrollment.
• serious or non-healing wound, ulcer or bone fracture.
• active bleeding or pathological condition that carries a high risk of bleeding (e.g., tumor involving major vessels or known varices).