[Therapy-induced leukemia -- an underestimated complication of antineoplastic chemotherapy?].

Alkylating agents and topoisomerase II inhibitors are mutagenic cytotoxic drugs which may induce therapy-related acute myeloid leukemia or myelodysplasia. The frequency of these complications depends on the type of agent used, its dosage, and the duration of treatment. Commonly used protocols for adjuvant chemotherapy of breast cancer, such as the CMF or AC protocols, are associated with a leukemia rate of 0.2 to 0.5 % after 10 years. Intensification of chemotherapy or additional radiotherapy lead to a significant increase in the incidence of leukemia. The prognosis of therapy-related leukemia is dismal. Therefore, it appears mandatory to restrict adjuvant chemotherapy to those patients who are the most likely to benefit from it.