Clinical Importance of CDKN2A Loss and Monosomy 10 in Pilocytic Astrocytoma

This case of a radiation-naive patient with pilocytic astrocytoma highlights how deletions of CDKN2A (cyclin-dependent kinase Inhibitor 2A) and PTEN (phosphatase and tensin homolog) portended a poor clinical outcome. Pilocytic astrocytomas are grade 1 tumors usually occurring in children and young adults with KIAA1549-BRAF fusion defining the majority of pilocytic astrocytomas. The presence of CDKN2A and PTEN loss may be associated with aggressive biology in pilocytic astrocytoma and further studies should include comprehensive genomics in a larger series of adult pilocytic astrocytoma to evaluate this previously unreported finding. Providers need to be aware of this possibility given the potential for poor outcomes.