High-resolution genomic analysis in Waldenström's macroglobulinemia identifies disease-specific and common abnormalities with marginal zone lymphomas.

Cytogenetic analyses have been historically limited in Waldenström's macroglobulinemia (WM) by the difficulty to obtain tumor metaphases. Thus, few recurrent karyotypic abnormalities have been reported and the molecular consequences of these imbalances are largely unknown. We used an array-based comparative genomic hybridization approach to better characterize the recurrent chromosome abnormalities associated with WM pathogenesis and to compare them with the publicly available findings in other B-cell neoplasias. The majority of the recurrent chromosome abnormalities identified in WM were shared with marginal zone lymphomas (MZL), as deletions of 6q23 and 13q14 and gains of 3q13-q28, 6p and 18q. On the other hand, gains of 4q and 8q were recurrently identified in WM but have not been described as being common abnormalities in MZL. The genetic consequences of these specific abnormalities remain elusive and further studies are critical to refine the search and to precise the molecular pathways affected by these abnormalities.