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 acute promyelocytic leukemia (APL) a potentially curable leukemia. Late sequelae of the treatment of APL have therefore become an important consideration in the overall treatment strategy. We report a patient with APL who achieved complete clinical and molecular remission after treatment with the topoisomerase 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 complex cytogenetic aberrations, including deletion of the long arm of chromosome 5, monosomy 7, but without rearrangement of the MLL gene/11q23. Interestingly, this case would be classified clinically as "epipodophyllotoxin related MDS," but pathologically as "alkylating-agent related MDS" according to the recently proposed World Health Organization (WHO) classification system for MDS. This case of t-MDS in an APL patient in durable remission highlights the importance of avoiding long-term treatment related toxicities, as APL is a potentially curable leukemia. Copyright (C) 2001 by W.B. Saunders Company.