Tremendous advances have been made in the genetic characterization and classification of adult brain tumors, but the classification of pediatric brain tumors with respect to their genetic characteristics has not been as well characterized. In the 2016 WHO Classification of Tumors of the Central Nervous System, a new class of brain tumors was described: diffuse midline glioma with histone H3 K27M mutation. This tumor occurs predominantly in children, and the presence of the histone H3 K27M mutation has been associated with worse patient outcomes.1 In our manuscript, we characterized the MR imaging patterns of diffuse midline gliomas that had the histone H3 mutation and compared them with diffuse midline gliomas with wild-type histone H3.2 We were surprised to discover that there were no qualitative differences in the imaging appearances of diffuse midline gliomas that had the histone H3 K27M mutation compared with the wild-type tumors. In our manuscript, we provided a detailed imaging characterization of this new class of tumors in a large cohort of children, which will serve as an important reference for neuroradiologists and general radiologists in practice.
Our work was enthusiastically welcomed by the imaging community at national and international meetings, including the ASNR 2016 meeting,3 because it was the first work to characterize the imaging features for this new class of tumors in a large cohort of patients.