Lenalidomide treatment for recurrent adult T-cell leukemia/lymphoma after allogeneic hematopoietic cell transplantation.

Patients with recurrent adult T-cell leukemia/lymphoma (ATL) after allogeneic hematopoietic cell transplantation (allo-HCT) have a dismal prognosis. We retrospectively evaluated the safety and efficacy of lenalidomide (LEN) in 11 consecutive patients with recurrent ATL after allo-HCT. The median time from allo-HCT to ATL recurrence was 111 days (range, 20-1476), and that from allo-HCT to the initiation of LEN was 162 days (range, 43-1560). The median initial daily dose of LEN was 10 mg (range, 5-25), and the median duration of LEN treatment was 37 days (range, 3-1078). Three patients (27%) achieved complete response and two (18%) achieved partial response (PR). The rates of complete or PR according to the involved site were 57% for skin and 50% for nodal or extranodal lesions. With a median follow-up of 1033 days (range, 601-1465) among survivors, the 1-year probability of overall survival (OS) after ATL recurrence was 55%. Grade ≥3 toxicities included cytopenia (n = 4), superficial vein thrombosis (n = 1), and deep vein thrombosis (n = 1). Graft-versus-host disease (GVHD) newly developed in five patients (45%) and worsened in four patients (36%). The median duration from the initiation of LEN to GVHD onset or worsening was 5 days (range, 1-9). GVHD was manageable in all patients. Seven patients received mogamulizumab (MOG) for recurrent ATL before LEN treatment. The overall response rates to LEN were 57% in patients who had previously received MOG and 25% in those who had not. The 1-year probabilities of OS after recurrent ATL were 71% in patients who had previously received MOG and 25% in those who had not. Although cytopenia and GVHD are common among patients with recurrent ATL after allo-HCT, LEN may improve survival. Administering MOG before LEN may augment treatment efficacy in the allo-HCT population.