Next-generation sequencing in chronic lymphocytic leukemia.

The use of next-generation sequencing (NGS) has expanded our knowledge of the genomic alterations in chronic lymphocytic leukemia (CLL) and provides new tools for analyzing leukemic clonal architecture. Recent studies have demonstrated substantial differences in genomic alterations between mutated and unmutated IGHV subgroups, which reflect distinct molecular pathways and mutagenic mechanisms in the pathogenesis of the disease. The mutational profile of CLL can be characterized by a relatively low number of somatic mutations per case, few recurrent mutations at moderate frequency (5%-15%) and a long tail of recurrent lower frequency somatic mutations. Functional and clinical studies of novel mutations have uncovered new mechanisms involved in the pathogenesis of the disease, revealing new insights into CLL molecular evolution that could ultimately translate into improvements in the management of patients. The clonal architecture of CLL shows striking heterogeneity between patients, which could have important clinical implications. In summary, NGS studies of CLL are expanding our fundamental knowledge on the molecular mechanisms involved in the pathogenesis of the disease and offering new perspectives for the clinical management of the patients.