Combination Chemotherapy and Bevacizumab With or Without Radiation Therapy in Treating Patients With Locally Advanced Rectal Cancer

DISEASE CHARACTERISTICS:

• Histologically or pathologically confirmed adenocarcinoma of the rectum

  • Clinical stage T1, N1; T2, N1; T3, N0; or T3, N1 by endorectal ultrasonography (ERUS)

    • No bulky N2 disease by either ERUS or MRI

    • No primary fixed or unresectable (clinical stage T4) rectal cancer or recurrent colorectal cancer limited to the pelvis

      • Primary unresectable rectal cancer is defined as a primary rectal tumor which on the basis of either physical exam, ERUS or pelvic MRI is deemed to be adherent or fixed to adjacent pelvic structures

• Must be a candidate for all of the following:

  • Neoadjuvant chemoradiotherapy
  • Systemic therapy with fluorouracil, leucovorin calcium, oxaliplatin (FOLFOX), and bevacizumab
  • Complete surgical resection via low anterior resection prior to administration of any therapy
• No low-lying tumors deemed to require an abdominal perineal resection
• No large or bulky tumors that require a diverting colostomy or placement of an endorectal stent prior to treatment initiation
• No clinical evidence of metastatic disease

PATIENT CHARACTERISTICS:

• ECOG performance status 0-2
• Absolute neutrophil count ≥ 1,500/mm^3
• Platelet count > 150,000/mm^3
• Hemoglobin > 8.0 g/dL
• Creatinine ≤ 1.5 times upper limit of normal
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception during and for 4 weeks after completion of study therapy
• No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer or carcinoma in situ of the cervix

• No arterial thrombotic event within the past 6 months, including stable or unstable angina, myocardial infarction (MI), or cerebral vascular accident (CVA)

  • Deep venous thrombosis, pulmonary embolus, MI, CVA, atrial fibrillation, or any other conditions occurring more than 6 months ago allowed provided patient is on stable doses of anticoagulant therapy
• No other medical or psychiatric condition or disease that would preclude study therapy

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics
• No prior chemotherapy or surgery for rectal cancer
• No prior pelvic radiotherapy

• No other concurrent experimental therapy, including any of the following:

  • Chemotherapy
  • Radiotherapy
  • Hormonal therapy
  • Antibody therapy
  • Immunotherapy
  • Gene therapy
  • Vaccine therapy
  • Angiogenesis inhibitors
  • Matrix metalloprotease inhibitors
  • Thalidomide
  • Anti-vascular endothelial growth factor/Flk-1 monoclonal antibody
  • Any other experimental drugs