Therapy-related myelodysplastic syndrome after eradication of acute promyelocytic leukemia: Cytogenetic and molecular features

The use of all trans-retinoic acid and combination chemotherapy has made ac ute promyelocytic leukemia (APL) a potentially curable leukemia. Late seque lae of the treatment of APL have therefore become an important consideratio n in the overall treatment strategy. We report a patient with APL who achie ved complete clinical and molecular remission after treatment with the topo isomerase II inhibitors daunorubicin, mitoxantrone, etoposide, and the anti -metabolite cytosine arabinoside. Seven years later, she developed therapy- related myelodysplastic syndrome (t-MDS) without any evidence of relapse of the APL clone. Karyotypic and molecular cytogenetic analysis showed comple x cytogenetic aberrations, including deletion of the long arm of chromosome 5, monosomy 7, but without rearrangement of the MLL gene/11q23. Interestin gly, this case would be classified clinically as "epipodophyllotoxin relate d MDS," but pathologically as "alkylating-agent related MDS" according to t he recently proposed World Health Organization (WHO) classification system for MDS. This case of t-MDS in an APL patient in durable remission highligh ts the importance of avoiding long-term treatment related toxicities, as AP L is a potentially curable leukemia. Copyright (C) 2001 by W.B. Saunders Co mpany.