NHERF1 is a marker for ependymoma. A. Comparative IHC with NHERF1 and EMA antibodies on serial sections from an ependymoma case shows microlumen detection only by NHERF1. The EMA versus NHERF1 staining was similarly performed in all the ependymomas (E) and in the NHERF1-positive anaplastic ependymomas (AE), and the quantification is shown in the graph. B. Quantification of microlumen density in ependymal tumors. E, ependymoma; SE, subependymoma. C. Quantification of the ring-like structures labeled by NHERF in ependymoma (E) and anaplastic ependymoma (AE) tumors. D. IHC with NHERF1 antibody in ependymoma variants shows microlumen labeling. E. Extent of NHERF1 microlumen labeling in ependymoma (E), pediatric anaplastic ependymoma (AEped) and adult anaplastic ependymoma (AEadult) illustrates significant NHERF1 loss in the latter. F. NHERF1 IHC of an anaplastic ependymoma case containing areas of classical ependymoma morphology (left) and areas of anaplasia (right) shows almost complete loss of NHERF1-labeled microlumens from the anaplastic component.