We selected a series of 63 primary diffuse large B-cell lymphomas (DLBCLs) of bone collected in tissue microarrays from centers in France and Brazil. These cases were classified according to the expression of antigens associated with germinal center (GC; n = 42) or non-GC (n = 21) stages of B-cell differentiation. By fluorescence in situ hybridization, we found a substantial number of cases with a rearrangement of BCL2 (9/32) and c -MYC (n = 3), whereas the PAX5, BCL6, BCL1 cyclin D1, and ALK genes were in germline configuration. It is interesting that 1 case, with a GC phenotype, showed dual BCL2 and c -MYC rearrangement. The majority of the cases with rearrangements were of the GC phenotype. These results, associated with the lack of BCL6 rearrangement, suggest that bone DLBCL represents a specific group within extranodal B-cell lymphomas.