CDKN2A (and adjacent CDKN2B) loss has been previously identified in a small minority of gangliogliomas as well as in other pediatric CNS tumors, such as pleomorphic xanthroastrocytoma (where CDKN2A/B loss is typical) [22, 60, 70]. The gene discussed is CDKN2B; the disease is central nervous system neoplasm.