Cytogenetic and molecular characterization of T-cell acute lymphoblastic leukemia as a second tumor after anaplastic large-cell lymphoma in a boy

We report a case of acute T-cell lymphoblastic leukemia which developed in a hoy 8.5 years after successful treatment for anaplastic large-cell lymphoma. Cytogenetic and molecular characterizations of the second tumor were performed. The cytogenetic investigation revealed a complex pattern of karyotypic alterations, including double minutes, ring chromosomes, and a duplication of the p21-32 region of chromosome 1. The microsatellite DNA analysis excluded rearrangement or deletion of the TALI gene in the tumor cells; rearrangements of the MLL gene were excluded by Southern blot analysis. To the best of our knowledge, this is the first report of T-cell lymphoblastic leukemia arising after treatment of CD 30(+) anaplastic large-cell lymphoma. The different T-cell receptor rearrangement evidenced in the two tumors indicates that this second malignancy most likely emerged de novo, but was plausibly related to the previous radiation and chemotherapy. (C) 1999, Ferrata Storti Foundation.