Childhood acute lymphoblastic leukemia with equivocal chromosome markers of the t(I;I9) translocation

✍ Scribed by Leonid V. Filatov; Frederick G. Behm; Ching-Hon Pui; David R. Head; James R. Downing; Susana C. Raimondi

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 399 KB
• Volume: 13
• Category: Article
• ISSN: 1045-2257
• DOI: 10.1002/gcc.2870130205

✦ Synopsis

The t(1;19)(q23;p13) or its derivative encodes an UA-PBXI fusion transcript and protein that has been shown to have important prognostic and therapeutic implications in patients with acute lymphoblastic leukemia (ALL). We describe two childhood cases in which a der(22)t( I ;22)(q21-23;pI 3) cytogenetically mimicked a der( I9)t( I; I9)(q23;p 13). In one case, which was phenotyped as early pre-B ALL with hyperdiploidy but lacked evidence of an UA-PBXI gene fusion by molecular study, the poor banding quality of chromosomes led to misinterpretation of the cytogenetic findings; a correct diagnosis was established only after analysis by the fluorescence in situ hybridization (FISH) method. The second case, which was classified as pseudodiploid pre-B ALL, had both a derivative I 9 and a derivative 22 but lacked sufficient cells for evaluation of UA-PBXI gene fusion. This case was included in order to compare the der( 19)t( I; 19) and the der(22)t( 1;22) and to pinpoint the difficulty in distinguishing these markers. FISH analysis can resolve diagnostic uncertainty in cases of ALL with equivocal chromosome I9 markers. Genes Chrornosom Cancer 13:99-/03 (1995).