Study of Lenalidomide(Revlimid) Plus Rituximab (Revlirit Regimen) in Elderly Patients With Relapsed/Refractory Diffuse Large B-cell Lymphoma (DLBCL)

Inclusion Criteria: * Understand and voluntarily sign an informed consent form. * Be = 65 years of age at the time of signing the informed consent form. * Able to adhere to the study visit schedule and other protocol requirements. * Patients with histological confirmation of DLBCL. * Stage of disease at study entry may include stage II-III-IV according to Ann Arbor Classification * Patients must have failed at least one prior treatments * ECOG performance status of equal or less than 2 at study entry * nLaboratory test results within these ranges: * Absolute neutrophil count equal or major than 1.0 x 109/L * Platelet count equal or major than 50 x 109/L * Serum creatinine equal or less than 2.0 mg/dL * Total bilirubin equal or less than 1.5 mg/dL * AST (SGOT) and ALT (SGPT) equal or less than 2 x ULN or equal or less 5 x ULN if hepatic metastases are present * Hemoglobin equal or major than 8 g/dl * Females of childbearing potential (FCBP) must agree to use two reliable forms of contraception simultaneously or to practice complete abstinence from heterosexual intercourse during the following time periods related to this study: 1. for at least 28days before starting study drug 2. while participating in the study 3. for at least 28 days after discontinuation from the study. The two methods of reliable contraception must include one highly effective method (i.e. intrauterine device (IUD), hormonal \[birth control pills, injections, or implants\], tubal ligation, partner's vasectomy) and one additional effective (barrier) method (i.e. latex condom,diaphragm, cervical cap). FCBP must be referred to a qualified provider of contraceptive methods if needed. * Disease free of prior malignancies for equal or major 5 years with exception of currently treated basal cell, squamous cell carcinoma of the skin, or carcinoma "insitu" of the cervix or breast * Able to take aspirin (81 or 325 mg) daily as prophylactic anticoagulation. (patients intolerant to ASA may use warfarin or low molecular weight heparin). Exclusion Criteria: * Any serious medical condition, laboratory abnormality, or psychiatric illness that would prevent the subject from signing the informed consent form. * Pregnant or breast feeding females. (Lactating females must agree not to breast feed while taking lenalidomide). * Any condition, including the presence of laboratory abnormalities, which places the subject at unacceptable risk if he/she were to participate in the study or confounds the ability to interpret data from the study. * Use of any other experimental drug or therapy within 28 days of baseline. * Known hypersensitivity to thalidomide. * The development of erythema nodosum if characterized by a desquamating rash while taking thalidomide or similar drugs. * Any prior use of lenalidomide. * Concurrent use of other anti-cancer agents or treatments. * Known positive for HIV or infectious hepatitis, type A, B or C.