Secondary genomic alterations in non-Hodgkin's lymphomas: tumor-specific profiles with impact on clinical behavior.

Lymphoid neoplasms are a very heterogeneous group of tumors with different biological characteristics and clinical evolutions. Current knowledge about these neoplasms has increased dramatically thanks to multidisciplinary research integrating data from morphological and phenotypic studies to molecular and genetic approaches. The heterogeneity in these neoplasms is due in part to the diversity of the cell populations of the immune system that give rise to these tumors and the complexity of the mechanisms involved in their pathogenesis. One of the most powerful methods for revealing the great complexity of these tumors is the analysis of their genetic alterations, which has allowed the definition of specific entities and provides the basis for the identification of target genes involved in the initiation and progression of the tumors. In the current issue three articles investigate the profile of genetic alterations in small B-cell lymphomas, mantle cell lymphomas (MCL) and diffuse large B-cell lymphomas (DLBCL) providing new insights on the relevance of these changes in the clinical and biological behavior of these neoplasms.