The majority of NF2-associated ependymomas are WHO grade II lesions with classic histology including perivascular pseudorosettes and ependymal rosettes (Fig. 6c, d), though features such as papillary architecture (Fig. 6e) and other histologic subtypes including myxopapillary, tanycytic, and anaplastic ependymomas may be observed. The gene discussed is NF2; the disease is ependymoma.