ATL is a distinct peripheral T-lymphocytic
malignancy associated with human T-cell lymphotropic virus type I (HTLV-1). The diversity in clinical features and prognosis of patients with this disease has led to its subtype-classification into four categories, acute,
lymphoma, chronic, and smoldering types, defined by organ involvement, and LDH and
calcium values. In case of acute,
lymphoma, or unfavorable chronic subtypes (aggressive ATL), intensive
chemotherapy like the
LSG15 regimen (VCAP-
AMP-VECP) is usually recommended if outside of clinical trials, based on the results of a phase 3 trial. In case of favorable chronic or smoldering ATL (indolent ATL), watchful waiting until
disease progression has been recommended, although the long-term prognosis was inferior to those of, for instance, chronic
lymphoid leukemia. Retrospective analysis suggested that the combination of
interferon alpha and
zidovudine was apparently promising for the treatment of ATL, especially for types with leukemic manifestation. Allogeneic
hematopoietic stem cell transplantation (allo-HSCT) is also promising for the treatment of aggressive ATL possibly reflecting graft versus ATL effect. Several new agent trials for ATL are ongoing and in preparation, including a defucosylated humanized anti-
CC chemokine receptor 4 monoclonal antibody, IL2-fused with
diphtheria toxin,
histone deacetylase inhibitors, a
purine nucleoside phosphorylase inhibitor, a
proteasome inhibitor, and
lenalidomide.