Myelodysplasia and acute myeloid leukaemia following adjuvant chemotherapy for breast cancer using mitoxantrone and methotrexate with or without mitomycin.

BACKGROUND

Secondary acute myeloid leukaemia/myelodysplasia (t-AML, t-MDS) may occur following adjuvant chemotherapy for breast cancer and has been most frequently associated with alkylating agents. This complication is now being associated with an expanding list of chemotherapeutic agents including topoisomerase II poisons. Mitoxantrone is an agent with potential to cause t-AML and t-MDS and which is being used increasingly in the treatment of breast cancer.

PATIENTS AND METHODS

Fifty-nine patients who received mitoxantrone as part of adjuvant chemotherapy for breast cancer between 1986 and 1992 were studied to determine the incidence of t-AML and t-MDS.

RESULTS

With a median follow-up of 72 months, 2 cases of t-AML and 1 of t-MDS have occurred.

CONCLUSIONS

This 5% incidence of t-AML and t-MDS is high and likely related to mitoxantrone. Whereas this agent is effective and has acceptable toxicity in advanced disease, its incorporation into adjuvant treatment regimens cannot be recommended based on this experience.