Diffuse large B-cell lymphoma with concordant bone marrow involvement has peculiar genomic profile and poor clinical outcome

Bone marrow (BM) involvement in diffuse large B-cell lymphoma (DLBCL) can be morphologically discordant from the primary tumor. Concordant BM infiltration has been shown associated with a poorer outcome in patients treated with CHOP. In order to evaluate tumor-related factors leading to BM involvement in DLBCL, we performed an integrated analysis of i) genomic profiles obtained with a high-density genome wide SNP-based arrays ii) immunomorphological and iii) clinical data from 133 patients uniformly treated with R-CHOP. BM infiltration was found in 27 of 133 (20%) cases; and it was concordant in 18/27 (67%) cases. Concordant infiltration, but not discordant, influenced negatively OS, PFS and DFS and was associated with higher serum LDH, lower CR and higher PD rates. No association with cell of origin was found between BM+ and BM- DLBCL. As compared with BM- cases, BM+ DLBCL showed absence of 7q gain.