The purpose of the Phase I of the study is to evaluate the safety and the maximum-tolerated dose (MTD) of the combination R-ESHAP with lenalidomide as salvage therapy for patients with relapsed or refractory diffuse large B-cell lymphoma The purpose of the Phase II of the study is to evaluate ORR of LR-ESHAP in patients with relapsed or refractory DLBCL candidates to HDT and ASCT