Ten patients with enhancing disease will be enrolled in stage 1 for each cohort. If none of the 10 patients in a particular cohort achieves an OR based on bidimensional measurements, no additional patients with enhancing disease will be enrolled into that particular cohort. However, if 1 of the 10 patients with enhancing disease in a particular cohort achieves an OR, then an additional 10 patients with enhancing disease will be enrolled in stage 2 of the minimax design for that cohort, yielding a maximum of 20 patients with enhancing disease for that cohort. As exploratory endpoints, complete response (CR), partial response (PR), and progressive disease (PD) rates, as well as 6-, 12-, and 24-month overall survival (OS) will be analyzed.