4 research outputs found
Genomic characterization of pediatric Bâlymphoblastic lymphoma and Bâlymphoblastic leukemia using formalinâfixed tissues
BackgroundRecurrent genomic changes in Bâlymphoblastic leukemia (BâALL) identified by genomeâwide singleânucleotide polymorphism (SNP) microarray analysis provide important prognostic information, but gene copy number analysis of its rare lymphoma counterpart, Bâlymphoblastic lymphoma (BâLBL), is limited by the low incidence and lack of fresh tissue for genomic testing.ProcedureWe used molecular inversion probe (MIP) technology to analyze and compare copy number alterations (CNAs) in archival formalinâfixed paraffinâembedded pediatric BâLBL (n = 23) and BâALL (n = 55).ResultsSimilar to BâALL, CDKN2A/B deletions were the most common alteration identified in 6/23 (26%) BâLBL cases. Eleven of 23 (48%) BâLBL patients were hyperdiploid, but none showed triple trisomies (chromosomes 4, 10, and 17) characteristic of BâALL. IKZF1 and PAX5 deletions were observed in 13 and 17% of BâLBL, respectively, which was similar to the reported frequency in BâALL. Immunoglobulin light chain lambda (IGL) locus deletions consistent with normal light chain rearrangement were observed in 5/23 (22%) BâLBL cases, compared with only 1% in BâALL samples. None of the BâLBL cases showed abnormal, isolated VPREB1 deletion adjacent to IGL locus, which we identified in 25% of BâALL.ConclusionsOur study demonstrates that the copy number profile of BâLBL is distinct from BâALL, suggesting possible differences in pathogenesis between these closely related diseases.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137353/1/pbc26363.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137353/2/pbc26363_am.pd