PFS and OS related to pretreatment. (A) PFS and (B) OS in patients with and without lenalidomide (Len) pretreatment. (C) PFS and (D) OS in patients with and without bortezomib (Boz) pretreatment. (E) PFS and (F) OS in patients with or without pretreatment with both lenalidomide and bortezomib.