MEN1 and multiple endocrine neoplasia type 1: Notable in the evaluation of the primary diagnostic specimen was the biallelic somatic disruption of MEN1. MEN1 mutations, typically biallelic, have been infrequently reported in ependymoma, both in the context of familial MEN1 syndrome and sporadically (Kato et al. 1996; Urioste et al. 2002; Al-Salameh et al. 2010; Lee et al. 2016b), and appear to occur in both high- and low-grade tumors of any location.