 Number of Planned Patients 20 patients will be enrolled in this study. Duration of Treatment Brentuximab vedotin will be administered as a single IV infusion on Day 1 of each 21-day cycle. Patients may continue on study treatment until disease progression or unacceptable toxicity. Patients who achieve stable disease or better should receive a minimum of 8, but no more than 16 cycles of study treatment. 