The primary study hypothesis was that decreases in Positron Emission Tomography (PET)-assessed tumor glucose metabolism (i.e., fluorodeoxyglucose [FDG] standardized uptake value [SUV]) following administration of 10 mg/kg robatumumab will exceed those following administration of 0.3 mg/kg robatumumab in participants with relapsed or recurrent colorectal cancer who had progressed after first-line chemotherapy.