LATE APPEARANCE OF A PHILADELPHIA TRANSLOCATION WITH MINOR-BCR ABL TRANSCRIPT IN A T(7-11)(P15-P15) ACUTE MYELOID-LEUKEMIA/

We describe a patient with a t(7;11)(p15;p15) acute myeloid leukemia w ho was subsequently found to harbor the Philadelphia (Ph) translocatio n, in addition to the t(7;11), at the second relapse. A BCR/ABL transc ript was detected at the second relapse by reverse transcription-polym erase chain reaction assay; the leukemic cells had a BCR/ABL fusion ge ne involving the minor breakpoint cluster region (minor-BCR; situated in intron 1 of the BCR gene). Although the Ph translocation is commonl y detected in de novo acute leukemia and chronic myeloid leukemia as t he primary leukemia-specific chromosomal translocation, our case sugge sts that this cytogenetic change might occur as an additional chromoso mal change in neoplastic cells. Moreover, minor-BCR/ABL rearrangements may also occur as a late appearance of Ph translocation.