Inclusion Criteria:

• NOTE: Patients may sign consent and be registered for this protocol prior to completion of assessment of criteria 6.1.1 and 6.1.2, (assuming all other eligibility criteria are met) so that endocolonic ultrasound and biopsy may be performed on study; as these procedures may be necessary to determine TNM staging and/or histopathology; however criteria 6.1.1 and 6.1.2 must be successfully met prior to patient receiving chemotherapy on this trial.
• 6.1.1 Clinical T1N1-2/T2N1-2/T3N0/T3N1-2/T4Ni-N2 adenocarcinomas of the colon determined by endocolonic ultrasound (ECUS) performed at MSKCC.
• 6.1.2 Colonoscopy with endoscopic biopsy of tumor at MSKCC for disease confirmation and correlative studies. Pathological confirmation of adenocarcinoma or poorly differentiated carcinoma as the primary histology.
• CT or MRI scans (done within 30 days of registration) of the Chest, Abdomen and Pelvis all without clear evidence of distant metastatic (M1) disease.
• Candidates for systemic therapy with FOLFOX and bevacizumab based on the opinion of the primary treating medical oncologist.
• Candidates for complete surgical resection prior to administration of any therapy.
• Performance status of ECOG 0 or 1.
• Patients must be of age ≥18 years.
• ANC ≥ 1.5 cells/mm3, PLT >150,000/mm3.
• Serum creatinine < or = to 1.5 OR creatinine clearance (measured or calculated) greater than 60 ml/min.

Exclusion Criteria:

• Primary tumor clearly unresectable.
• Tumors with neuroendocrine histology.
• Patients with tumors that require placement of an endocolonic stent prior to treatment initiation.
• Patients with a history of stroke or TIA.
• Patients with history of thrombotic episodes such as deep venous thrombosis, pulmonary embolus, MI, or CVA occurring more than 12 months prior to enrollment may be considered for protocol participation provided that they are on stable doses of anticoagulant therapy. Similarly, patients anticoagulated for atrial fibrillation or other conditions may participate provided that they are on stable dose of anticoagulant therapy. Clinicians must note the higher risk of bevacizumab therapy amongst patients with history of thromboembolic disorders and consideration for participation is at the discretion of the treating physician.
• No other experimental therapies (including chemotherapy, radiation, hormonal treatment, antibody therapy, immunotherapy, gene therapy, vaccine therapy, angiogenesis inhibitors, matrix metalloprotease inhibitors, thalidomide, anti-VEGF/Flk-1 monoclonal antibody or other experimental drugs) of any kind are permitted while the patient is receiving study treatment.
• Women of childbearing potential (WOCBP) who are unwilling or unable to use an acceptable method to avoid pregnancy for the entire study period and for up to 6 months after the study. Subjects who are men must also agree to use effective contraception.
• Note: Women of childbearing potential (WOCBP) must be using an adequate method of contraception to avoid pregnancy throughout the study and for up to 6 months after the study in such a manner that the risk of pregnancy is minimized.
• WOCBP include any female who has experienced menarche and who has not undergone successful surgical sterilization (hysterectomy, bilateral tubal ligation or bilateral oophorectomy) or is not postmenopausal [defined as amenorrhea ≥ 12 consecutive months; or women on hormone replacement therapy (HRT) with documented serum follicle stimulating hormone (FSH) level > 35mIU/mL]. Even women who are using oral, implanted or injectable contraceptive hormones or mechanical products such as an intrauterine device or barrier methods (diaphragm, condoms, spermicides) to prevent pregnancy or practicing abstinence or where partner is sterile (e.g., vasectomy), should be considered to be of child bearing potential.
• WOCBP must have a negative serum or urine pregnancy test (minimum sensitivity 25 IU/L or equivalent units of HCG) within 72 hours prior to the start of study medication.
• Women who are pregnant or breast feeding. Note: women with a positive pregnancy test on enrollment or prior to study drug administration will be removed from study.
• Patients with any other concurrent medical or psychiatric condition or disease which, in the investigator's judgment, would make the patient inappropriate for entry into this study.
• Patients with a history in the past five years of a prior malignancy, except for adequately treated basal cell or squamous cell skin cancer or in situ cervical cancer. Inadequately controlled, persistent (on more than one occasion) hypertension (defined as systolic blood pressure >150 mmHg and/or diastolic blood pressure > 100 mmHg).
• Prior history of hypertensive crisis or hypertensive encephalopathy.
• New York Heart Association (NYHA) Grade II or greater congestive heart failure
• Significant vascular disease (e.g., aortic aneurysm, requiring surgical repair or recent peripheral arterial thrombosis) within 6 months prior to Day 1
• Evidence of bleeding diathesis or significant coagulopathy (in the absence of therapeutic anticoagulation)
• History of abdominal fistula or gastrointestinal perforation within 6 months prior to Day 1
• Serious, non-healing wound, active ulcer, or untreated bone fracture (adjuvant trials: bone fractures must be healed
• Proteinuria as demonstrated by a UPC ratio ≥ 1.0 at screening
• Known hypersensitivity to any component of bevacizumab