Favorable Early Response of Secondary Chronic Myeloid Leukemia to Imatinib

Second malignant neoplasms are gradually becoming a recognized long-term complication of successful cancer treatment, and they usually respond poorly to conventional therapy and have an unfavorable outcome. Chronic myeloid leukemia (CML) is a clonal panmyelopathy, rarely seen in children with a specific cytogenetic aberration-the Philadelphia chromosome. The translocation generates an aberrant tyrosine kinase, which drives the malignant process in CML and which is also the molecular target for successful treatment of CML with imatinib. It is also exceedingly rare as a secondary malignant neoplasm in both adults and children. We report two cases of secondary CML. The first occurred after successful treatment for nasopharyngeal carcinoma in a child, and the second after treatment for lymphoma in an adolescent. Both patients had an excellent response to treatment with imatinib and attained complete cytogenetic remissions. We conclude that secondary CML may respond favorably to treatment with imatinib.