We describe a case of an adult with a progressive <i>BRAF V600E</i> mutant spinal cord ganglioglioma 9 years after surgery who was treated with vemurafenib.
In the third case, where the interval spanned multiple decades, the GG was found to be positive for both BRAFp.V600E immunohistochemistry (IHC) and for the KIAA1549-BRAF fusion.
The review of imaging features indicated that cyst formation is associated with the existence of KIAA1549-BRAF fusion in PA and GG and the lack of BRAF mutation in GG.
Here, we show that the oncogenic BRAF somatic mutation p.Val600Glu (V600E) in developing neurons underlies intrinsic epileptogenicity in ganglioglioma, one of the leading causes of intractable epilepsy<sup>2</sup>.
As co-occurrence of H3 K27M and BRAFV600E mutations has been reported in midline tumors and anaplastic GG, we searched for BRAF V600E and H3 K27M mutations in a series of 54 paediatric midline grade I GG (midline GG) to determine the frequency of double mutations and its relevance for prognosis.
Some glial-neuronal tumors (GNT) (pleomorphic xantho-astrocytoma [PXA], ganglioglioma [GG]) display BRAF-V600E mutation, which represents a diagnostic clue to these entities.
We identified novel ALK fusions in a neuroblastoma (BEND5-ALK) and an astrocytoma (PPP1CB-ALK), novel BRAF fusions in an astrocytoma (BCAS1-BRAF) and a ganglioglioma (TMEM106B-BRAF), and a novel PAX3-GLI2 fusion in a rhabdomyosarcoma.
BRAF mutations are most frequently detected in certain subtypes of low-grade glioma, such as pilocytic astrocytoma (PA), pleomorphic xanthoastrocytoma (PXA), ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNT).
This article reports on the clinical history, molecular findings, and treatment response in a patient with BRAF V600-mutated high-grade glioma arising from ganglioglioma.
An extensive literature search revealed that our patient is the fourth case of pigmented ganglioglioma described in the literature and was positive for BRAFV600E mutation by molecular studies.
Activation of the MAP Kinase (MAPK) pathway caused by the BRAFV600E mutation or the KIAA1549-BRAF fusion has been reported in pediatric GG and PA, respectively.
BRAFV600E mutation, a genetic abnormality seen in a significant percentage of pleomorphic xanthoastrocytomas and GGs, was assessed by polymerase chain reaction and identified in the tumor.
Direct analysis demonstrated loss of p19 expression and p53 mutation in the malignant areas, highly suggestive of these alterations being involved in the malignant progression of the ganglioglioma.
The authors report here the first unequivocal case of a ganglioglioma harboring aberrant TP53 product that was expressed predominantly in the neuronal component.
The present case is unusual in four aspects: (i) it arose from a low-grade ganglioglioma in the absence of previous radiation or chemotherapy, which is the fourth reported case; (ii) the original tumor showed a high proliferative index on flow cytometry but a low Ki-67 labeling index, implying that the application of flow cytometry might play a certain role in predicting biological and clinical behavior of low grade gangliogliomas; (iii) p53 mutation and deletion appeared in the secondary glioblastoma, which was not shown in the original well-differentiated ganglioglioma; and (iv) the transformed glioblastoma showed p16 inactivation detected by methylation and deletion, which are relatively uncommon genetic events in secondary glioblastomas.