Two patterns of chromosomal breakpoint locations on the immunoglobulin heavy-chain locus in B-cell lymphomas with t(3;14)(q27;q32): relevance to histology

摘要

The t(3;14)(q27;q32) is the most common translocation involving BCL6 in B-cell lymphoma. Although this translocation was predominantly associated with diffuse large B-cell lymphoma (DLBCL), recent studies have shown that it can also be found in follicular lymphomas (FL), often associated with a large cell component. To further investigate the relationship that might exist between this translocation and the phenotype of the tumors, we studied 34 lymphomas with a t(3;14)(q27;q32). Twenty cases were DLBCL, 14 FL and most cases, regardless of histology, were negative for the expression of CD10 (26/32, 81%). We identified the IGH switch region involved in the translocation for 32 cases. Our data indicate that in DLBCL most breakpoints involve the switch (17/19; 89%), whereas in FL most involve a switch (9/13; 70%) (P=0.0016, Fisher's exact test). This correlation between the histology and the structure of the translocated allele suggests that the lymphomas with S and S translocations may originate from different cells, or that the substituted regulatory regions that come to deregulate BCL6 may affect the presentation of the disease.