ARM B: Patients receive oxaliplatin, leucovorin calcium, and fluorouracil as in Arm A and bevacizumab IV over 30-90 minutes on day 1. Treatment repeats every 2 weeks for 12 courses in the absence of disease progression or unacceptable toxicity. Patients then receive bevacizumab alone for 12 additional courses in the absence of disease progression or unacceptable toxicity.