Gangliogliomas are predominantly low-grade
primary brain tumors comprised of neuronal and glial components that are found in both pediatric and young adult populations. In the majority of cases, surgical resection of these
tumors is curative. However,
tumor location in eloquent centers of the brain can make surgical intervention inappropriate. Additionally, a subset of
tumors progress to anaplastic
ganglioglioma which carries a poor prognosis, despite resection. Activating mutations in the MAPK pathway, such as BRAF V600E, have been identified in many of these
tumors.
Tumors carrying such mutations have demonstrated susceptibility to
MEK inhibition
therapy. However, there remains a subset of
ganglioglioma that do not contain a known mutation in the MAPK pathway and thus have not been targeted with
MEK inhibition
therapy. Here, we present a young adult
ganglioglioma patient without identified MAPK pathway activation mutations who demonstrated a significant and sustained response to
MEK inhibition with
trametinib.