Adult T-cell leukemia-lymphoma complicated by Takotsubo cardiomyopathy and HTLV-1-associated myelopathy after treatment with the anti-CCR4 antibody mogamulizumab.

Adult T-cell leukemia-lymphoma (ATL) caused by human T-lymphotropic virus type 1 (HTLV-1) is generally associated with poor prognosis. The anti-CCR4 antibody mogamulizumab is one of the options for refractory or relapsed ATL. Mogamulizumab is intravenously administered as a single agent at a dose of 1.0 mg/kg once a week for 8 weeks. The overall response rate is reported to be 50%. Reported common adverse events after administration of mogamulizumab are leukocytopenia, infusion reaction, and skin rash. Although rare, mogamulizumab-associated cardiomyopathy has also been reported. HTLV-1 is also associated with a number of diseases, such as HTLV-1-associated myelopathy (HAM). Approximately 0.25% of infected individuals are estimated to develop HAM. HAM is an inflammatory disease of the central nervous system, which is characterized by slowly progressive spastic paresis of bilateral lower limbs and bladder-rectal disorder. Coexistence of ATL and HAM has rarely been reported. Here we present the case of a patient with ATL in whom Takotsubo cardiomyopathy and HAM developed after mogamulizumab administration.