Further more, the loss of p16 has been reported in some anaplastic PA (42,71), and a recent study involving 73 anaplastic astrocytomas with pilocytic features found that these gliomas are characterized by frequent MAPK pathway alterations, CDKN2A/B deletion, ATRX loss, and unfavorable prognosis (72). This evidence concerns the gene CDKN2A and anaplastic astrocytoma.