Mitoxantrone therapy in multiple sclerosis and acute leukaemia: a case report out of 644 treated patients.

As a rare complication of mitoxantrone (MITOX) therapy in multiple sclerosis (MS), a therapy-related acute leukaemia (TRAL) may develop. The incidence is difficult to estimate, as frequently single cases are reported, up to now a total of eight MS patients. Here we report a new case out of 644 patients. This is a 45-year-old female patient with secondary progressive MS who developed TRAL after a total dose of 48 mg/m2 MITOX. The TRAL was classified as acute myeloblastic leukaemia (AML) M4eo and showed an inversion of chromosome 16 and a partial trisomy 11. Her TRAL was treated with chemotherapy followed by allogeneic bone marrow transplantation. It responded well to the transplantation, whereas the MS symptoms initially worsened but have nearly returned to the pretransplantation level. This report brings the currently published frequency of MITOX-associated TRAL in MS therapy to five in a total of 2336 treated MS patients, representing an incidence of 0.21%.