Molecular Diagnostics of Non-Hodgkin Lymphoma.

Non-Hodgkin lymphoma encompasses a diverse group of B-cell and T-cell neoplasms. Current classification is based on clinical information, histologic assessment, immunophenotypic characteristics, and molecular alterations. A wide range of genetic alterations, including large chromosomal structural rearrangements, aneuploidies, point mutations, and copy number alterations, have been reported across all types of lymphomas. Many of these are now incorporated into the World Health Organization-defined criteria for the diagnostic evaluation of patients with lymphoid proliferations and, therefore, their accurate identification is paramount for diagnosis, subclassification, and selection of treatment. In addition to their value in the diagnostic setting, many alterations that are not routinely evaluated in standard clinical practice may still define specific disease entities as they have important implications in risk stratification, as well as roles in emerging alternate therapies and disease monitoring. Because of the complexity and range of alterations, their accurate and sensitive assessment requires a careful selection of technology. Here, we discuss the most commonly used molecular techniques in current clinical practice and highlight some of the benefits and pitfalls based on the type of alteration.