RELA and ependymoma: The 2016 CNS tumor classification categorized SP-EPs as SE (WHO grade 1), MPE (WHO grade 1), the classic ependymoma with its three histological subtypes, papillary, clear cell, and tanycytic (WHO grade 2), anaplastic ependymoma (WHO grade 3) and one genetically defined type of ependymoma, RELA fusion‐positive (WHO grade 2/3) [20].