Molecular diagnostics on lymphoid malignancies

Context. - Molecular diagnostics for lymphoid malignancies traditionally has focused on helping to provide a diagnosis on a tissue sample. The field has undergone substantial technical and conceptual evolution during the past 2 decades, and its role has expanded to new arenas, such as monitoring disease activities and detecting alterations in genes that are known to have a significant impact on disease outcome. Objective. - To review the advances in molecular diagnostics on lymphoid malignancies, including recent developments that may facilitate the development of mechanism-based diagnosis for individualized therapy. Design. - The development of molecular diagnostics in lymphoid malignancies is briefly reviewed with emphasis on the recent use of gene expression profiling for identifying important diagnostic and prognostic signatures. Results. - Genome-scale investigations are becoming technically feasible and have provided promising results in the identification of new disease entities and new, molecularly defined prognosticators. This development can potentially revolutionize diagnostic medicine in the near future. As new genes or genetic pathways that affect the clinical and biologic behavior of tumors are defined and can be readily assayed, molecular diagnostics will be expected to provide this relevant information. Ideally, therapy will be based on this information, delivering the most appropriate treatment with the least toxicity. Conclusions. - Molecular diagnostics in the future will be moving toward a mechanism-based diagnosis for individualized therapy.