Diffuse large B-cell lymphoma (DLBCL) is a common lymphoid malignancy among adults in the developed world and accounts for about a third of all patients newly diagnosed with non-Hodgkin lymphoma each year. The prognosis of patients with DLBCL has improved over the past 10 years since the advent of chemoimmunotherapy regimens such as R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone). However, a significant number of patients still experience disease relapse or progression after first or second line therapy, and ~40% of patients will die within 5 years. In particular, elderly patients and those ineligible for high-dose chemotherapy due to comorbidities require effective salvage treatment options with favorable toxicity profile. Several novel therapeutic approaches have been proposed for these patients including monoclonal antibodies, radioimmunotherapy, proteasome inhibitors, mTOR inhibitors, and the immunomodulatory drugs such as thalidomide and lenalidomide.