The total study accrual will be up to 120 patients over a period of 24 months in order to provide 90 patients for randomization to the continuation regimen. Patients will be randomized 2:1 to receive the continuation regimen of 5-FU/LV + ziv-aflibercept (Arm 2, 60 patients) or 5-FU/LV alone (Arm 1, 30 patients).