[Necessity of Genetic Examination in Treatment for Hematological Malignancies]

Generally, hematological malignancies are morphologically diagnosed and classified. However, since their clinical characteristics are markedly heterogeneous, routinely used classification systems are not necessarily useful for the benefit of patients. Recent progress in the detection system for genetic alterations has revealed several mutations, which are associated with the development and/or progression of hematological malignancies, and the accumulation of data on the prognostic significance of recurrent genetic alterations has made more detailed risk stratification possible in patients with hematological malignancies. In acute myeloid leukemia (AML), prognostic risk classification based on cytogenetics has been established, while there is a clinical heterogeneity in the intermediate risk group, particularly in those with cytogenetically normal AML. The European LeukemiaNet (ELN) recommended a novel risk classification system based on the cytogenetic and genetic status. The long-term prognosis according to the ELN classification system was retrospectively evaluated in two well-established cohorts, and both analyses demonstrated that the ELN system is useful for further risk stratification of younger adult patients with CN-AML. A genetic diagnosis and classification system will provide important information for both patients and physicians, while the overall picture of molecular pathogenesis in hematological malignancies remains to be elucidated.