Incidence of therapy-related acute leukaemia in mitoxantrone-treated multiple sclerosis patients in Germany

Background: The incidence of therapy-related acute leukaemia (TRAL) in mitoxantrone treatment in multiple sclerosis (MS) is controversially discussed. Methods and results: In a retrospective meta-analysis from six centres, we observed six cases of acute myeloid leukaemia (AML) (incidence 0.41% for patients with mean follow up after end of treatment of 3.6 years, n = 1.156; incidence 0.25% for all patients, n = 2.261). Potential influencing factors such as myelotoxic or glucocorticosteroid pretreatment/cotreatment were present in all but one case of TRAL. Between 1990 and 2010, 11 cases of TRAL were reported to the Drug Commission of the German Medical Association (estimated risk of 0.09–0.13%). Conclusions: Regional differences in reported TRAL incidence may point to confounding cofactors such as administration protocols and cotreatments.