Therapy-related leukemia associated with chemotherapy, particularly alkylat
ing agents and topoisomerase II inhibitors, are being reported with increas
ing frequency in the literature mainly after breast cancer. We also observe
d an increasing number of such leukemias in the data base of the specialize
d registry of hematological malignancies of the Cote d'Or department. Betwe
en 1980 end 1998, 156 AML and RAEB-t were registered in women in Cote d'Or.
Among them, 12 occurred in women with breast cancer history (7.7%). Analys
is by period of time shows a significant increase in the proportion of ther
apy-related leukemia secondary to breast cancer (P < 0.02). Chemotherapy in
cluding topoisomerase II inhibitors was used in 10 cases in which mitoxantr
one was used in eight cases. In these eight cases, leukemia had clinical an
d biological characteristics usually described with topoisomerase II inhibi
tors but 44% were promyelocytic sub-type with the t(15;17) specific karyoty
pic abnormality. These data on a well-defined population demonstrate the in
creased proportion of therapy-related leukemia secondary to breast cancer,
probably due to the use of mitoxantrone.