[1422] Novel Recurrent Gains and Deletions in Adults with Anaplastic Large Cell Lymphoma

Steven D Held, Marsha C Kinney, Edward A Medina, Russell A Higgins. University of Texas Health Science Center at San Antonio, San Antonio, TX

Background: Anaplastic large cell lymphoma (ALCL) includes anaplastic lymphoma kinase (ALK)+ ALCL, ALK- ALCL, and primary cutaneous ALCL (PC-ALCL). We used oligonucleotide-based array comparative genomic hybridization (aCGH) to identify recurring genomic gains and losses in ALCL and to identify potential genes in altered regions that may play a cooperative role in the pathogenesis of ALCL.
Design: Potential cases of adult ALCL with frozen tissue were collected, with IRB consent, from the San Antonio Cancer Institute tumor bank. CD30 and ALK immunohistochemistry were performed on frozen or paraffin embedded tissue. Inclusion criteria were anaplastic morphology and strong expression of CD30 in all tumor cells. DNA was extracted from frozen samples, and oligonucleotide-based aCGH was performed. Genomic alterations affecting at least 40% of cases were further evaluated for genes of interest.
Results: Ten samples of ALCL (age range 25 to 77 years) were analyzed: 5 ALK+ ALCL, 4 ALK-ALCL, and 1 PC-ALCL. Novel deletions were identified in 4 regions: 6p21.32 (60%), two separate regions within 14q11.2 (70% and 40%), and 15q11.2 (40%). There were 5 regions of recurrent gain: 1p36.33 (50%), 1q21.1-q24.3 (40%), 8p11.23 (40%), 14q32.33 (60%), and 16p13.3 (40%). These 5 regions of recurrent gain have been previously described in pediatric ALK+ ALCL but not in adult ALCL using aCGH. Some genes in altered regions have been associated with cancer including SDF4, DVL1, ADAM3A, HLA-DRB1, and RAB40C. Genomic alterations were present in both ALK+ and ALK- ALCL without a preferential association with ALK expression.
Conclusions: Novel recurrent genomic alterations were identified in adult ALCL. These recurrent alterations potentially contain genes involved in the pathobiology of ALCL.
Category: Hematopathology

Tuesday, March 20, 2012 8:00 AM

Platform Session: Section C, Tuesday Morning

 

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