Trial on Lenalidomide Given as Maintenance Therapy for Relapsed Diffuse Large B Cell Lymphoma

Inclusion Criteria: * Age \> 65 years * Age \< 65 but not eligible to high-dose chemotherapy and autologous stem cell transplantation * Biopsy-proven DLBCL relapsed to previous combination chemotherapy regimen ± rituximab * PR (Partial Response) or CR (Complete Response) to second-line chemotherapy (ICE or DHAP/DHAOx or MINE regimen) + rituximab * ECOG (Eastern Cooperative Oncology Group) performance status score \< 4 * Female of childbearing potential (FCBP) must demonstrate to practice a proper contraception to avoid any pregnancy risk during the study and at least 28 days after the discontinuation of the study * Male subjects must agree to practice a proper contraception during any sexual contact with females childbearing potential Exclusion Criteria: * CNS (Central Nervous System) involvement * Prior ASCT * TTP (Time To Progression) \<6 months after first-line therapy * Use of experimental drugs during second-line salvage chemotherapy * Severe concomitant illnesses / medical conditions (e.g. impaired respiratory and/or cardiac function, uncontrolled diabetes mellitus ) * Active infectious disease * HIV, HBV (Hepatitis B Virus) or HCV (Hepatitis C Virus) - positivity * Impaired liver function (Bilirubin \>2 x upper normal limit; ALT (alanine aminotransferase) /AST (aspartate aminotransferase) /GGT (γ-glutamyltransferase) \> 3 x upper normal limit) at one month from salvage chemotherapy conclusion * Impaired renal function (creatinine clearance \<50 ml/min) at one month …