Clinical activity of lenalidomide in various lymphoma subtypes has been documented in several phase II trials. In patients with relapsed/refractory mantle cell lymphoma, the overall response rate (ORR) was 53% with PFS at 12 month 40%. In patients with aggressive lymphoma (mostly diffuse large B-cell subtype), the ORR was 35% with PFS at 12 months about 25%. There also have been many case reports of patients who achieved durable complete response to lenalidomide after failing multiple cytotoxic chemotherapy regimens.