Case report:
A previously healthy 12-year-old girl presented with a 12-month history
of intermittent right facial paresthesias which occasionally extended to
the right superior and inferior limbs, associated with variable
tonic-clonic movements, headaches, and aphasia. Video-EEG monitoring
showed left temporal/parietal ictal activity. A brain and spine magnetic
resonance imaging (MRI) identified a lesion involving the left insular
cortex and frontal operculum with extension into the deep white matter
suspicious of low-grade glioma (Fig1A, 1B). The patient was started on 3
different AED without efficacy in seizures control. Furthermore, and
secondary to her poor controlled epilepsy, she developed panic attacks
and symptoms of anxiety and depression, isolating herself at home from
friends and family. Ten days after the first scan, a functional MRI for
language localization with diffuse tensor imaging (DTI) was performed.
The lesion had significantly increased in size (Fig1C) and depicted a
close relationship with language areas and major white matter tracts
(arcuate fasciculus and corticospinal tract, Fig1D). Because of the high
risk associated with a radical surgery, a stereotactic biopsy was
performed without complications. The pathology review was consistent
with a WHO grade 1 ganglioglioma. The BRAF p.V600E mutation, in
addition to monoallelic CDKN2A deletion was identified by using
droplet digital PCR (ddPCR).
Treatment was initiated with dabrafenib at 150 mg BID. A few weeks into
therapy, seizures frequency decreased and two months later, they
stopped. After 4 months on dabrafenib, a follow-up MRI showed no
evidence of disease (Fig2). After 14 months, AED were discontinued with
no clinical signs nor epileptic activity in the EEG. Anxiety and
depression symptoms decreased, and the patient was able to go back to
her normal activities including school and sports. Therapy was overall
well tolerated. However, because of fatigue and headaches, the dosage
had to be decreased progressively to 75 mg BID with further good
tolerance and compliance. She is still in complete remission and
seizures free 30 months after diagnosis.