According to the 2016 classification by the World Health Organization (WHO), an ependymoma is traditionally classified into three histopathological subtypes, including WHO grade I (myxopapillary ependymoma, subependymoma), WHO grade II (ependymoma), WHO grade III (anaplastic ependymoma), and WHO grade II or III (RELA fusion-positive) (Table 1) [24]. This evidence concerns the gene RELA and subependymoma.