Expanding the spectrum of EWSR1-PATZ1 rearranged CNS tumors. An infantile case with leptomeningeal dissemination

We report on a case of EWSR1-PATZ1 rearranged brain tumor occurring in a 17 month-old child, originally interpreted as an infantile glioblastoma. Our case shows important analogies with the 2 previously reported cases, including the intraventricular location, the histologic appearance (pushing borders, oligodendrocyte-like morphology, rich vascular network) and the glioneural immunophenotype, supporting the role of these features as relevant clues to the diagnosis. On the other hand, our case displays unique characteristics, i.e. the onset in an infant, the presence of a focal high-grade component and the leptomeningeal dissemination, pointing to the importance of considering this entity in the differential diagnosis of an infantile glial/glioneural tumor.