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.