Angioimmunoblastic T-cell lymphoma (AITL) is characterized by an aggressive clinical course and unfavourable prognosis. Refractory AITL patients have very few treatment options. Lenalidomide has previously been reported to have clinical efficacy in this setting; however, long-term reports are limited. A 59-year-old man was referred to the hospital with fatigue, skin rash, weight loss and generalized lymphadenopathy and was diagnosed with AITL; clinical stage was IV B with bone marrow involvement. The patient had an unsatisfactory response despite three lines of conventional chemotherapy and radiotherapy. The patient received lenalidomide monotherapy (25 mg once daily) on days 1 to 21 of every 28-day cycle for six cycles, followed by maintenance therapy with six cycles of lenalidomide 15 mg once daily on days 1 to 21 of every 28-day cycle. A computed tomography scan was assessed before lenalidomide treatment, after the third cycle, at disease restaging 2 months after completion of the induction phase, every 3 months during the maintenance phase and every 6 months during the follow-up period. At the last evaluation, after a follow-up of 30 months, the patient maintained a clinical and radiological complete response. The treatment was well tolerated with manageable toxicity. Lenalidomide treatment demonstrated for the first time in the literature impressive and long-term clinical efficacy in a heavily pretreated chemorefractory AITL patient. Copyright © 2012 John Wiley & Sons, Ltd.