Pilocytic astrocytomas

Handb Clin Neurol. 2016:134:329-44. doi: 10.1016/B978-0-12-802997-8.00020-7.


Pilocytic astrocytoma (PA) is the most common pediatric brain tumor in children. PAs are a distinct histologic and biologic subset of glioma that have a slow growth rate and may even spontaneously regress. These tumors tend to arise in the cerebellum and chiasmatic/hypothalamic region, but can also occur in other regions of the central nervous system. Dissemination is uncommon, but may occur in newly diagnosed PAs. Alterations in the Ras/RAF/mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway (Ras/ERK) have been discovered in a majority of PAs, with KIAA1549-BRAF fusions being the most commonly identified alteration. Children with neurofibromatosis 1 are predisposed to developing PAs, primarily within the optic pathway. When required, treatment consists of surgery, chemotherapy, and/or radiation, although new molecular agents targeting the Ras/ERK and related signaling pathways are promising new approaches. The 10-year survival rates are greater than 90% in pediatric patients; however, they are poorer in adults. Tumors that are amenable to complete resection (i.e., cerebellum and cortex) have the best overall survival.

Keywords: BRAF; NF1; glioma; low grade; pilocytic astrocytoma; tumor.

Publication types

  • Review

MeSH terms

  • Astrocytoma* / metabolism
  • Astrocytoma* / pathology
  • Astrocytoma* / therapy
  • Brain Neoplasms* / metabolism
  • Brain Neoplasms* / pathology
  • Brain Neoplasms* / therapy
  • Child
  • Humans