YAP1 and ependymal tumor: Ependymal tumors were classified into supratentorial RELA positive (ST-EPN-RELA; n = 2), supratentorial YAP1 positive (ST-EPN-YAP; n = 2), posterior fossa type A (PF-EPN-A; n = 1), or posterior fossa type B (PF-EPN-B; n = 1), and one remained unclassified.