ETV6-RUNX1Rearrangement in Tunisian Pediatric B-Lineage Acute Lymphoblastic Leukemia

摘要

In this study, Forty-one out of fifty-seven Tunisian children with B-lineage acute lymphoblastic leukemia (B-ALL), and without cytogenetically detectable recurrent abnormalities at the time of the diagnosis, were evaluated by fluorescence in situ hybridization (FISH) for the t(12;21). This translocation leadsETV6-RUNX1(previouslyTEL-AML1) fusion gene. 16 patients (28%) hadETV6-RUNX1rearrangement. In addition to this rearrangement, two cases showed a loss of the normalETV6allele, and three others showed an extra signal of theRUNX1gene. Seven patients withoutETV6-RUNX1rearrangement showed extra signals of theRUNX1gene. One out of the 7 patients was also associated with a t(3;12) identified by FISH. This is the first Tunisian study in which we report the incidence of t(12;21) among childhood B-lineage ALL and in which we have found multiple copies ofRUNX1. Finally, our findings confirm that additional or secondary genetic changes are commonly encountered in pediatric B-lineage ALL withETV6-RUNX1gene fusion which is envisaged to play a pivotal role in disease progression.