Genomic aberrations in diffuse low-grade XXXX .

@entity1 @entity5 @entity11 @entity816 @entity3271
The current classification of diffuse low-grade @entity11 is based mainly on histopathological criteria, which cannot accurately predict the highly variable clinical course observed in @entity1 with such @entity5 . In an attempt to increase pathogenetic understanding of these @entity5 , we investigated 38 WHO @entity816 , @entity3271 , and @entity816 using a combination of G-band chromosome analysis and high-resolution comparative genomic hybridization (HR-CGH). Abnormal karyotypes were found in 41% of @entity5 . Karyotypes of @entity816 and @entity3271 were near-diploid whereas @entity816 also displayed near-tetraploid clones. The most common aberrations were losses of chromosomes X, Y, 3, 4, 6, and 11 and gains of chromosomes 8 and 12. The only recurrent structural rearrangement was del(6)(q21). HR-CGH analysis verified karyotyping findings but also revealed frequent losses at 1p, 17q, and 19q and gains of 7q, 10p, 11q, and 20p. Among the @entity5 were two gemistocytic @entity816 , a subgroup of diffuse @entity816 with a particular predisposition for progression but not studied cytogenetically before; one showed a near-diploid, complex karyotype with structural aberrations of chromosomes 1, 3, and 11 whereas both displayed simple aberrations including loss of 11p by HR-CGH. Our findings suggest that within diffuse low-grade @entity11 are genetically distinct entities that do not fit the currently used classification. In addition, @entity5 with complex chromosomal aberrations had a higher tendency for aggressive @entity5 behavior (shorter progression-free survival) than @entity5 displaying simple aberrations only (P = 0.07). This could help identify genetic subsets of @entity1 with @entity11 who might benefit from early antineoplastic therapy.
