A five year-old child with clear cell petro-clival meningioma: case report with clinical and histopathological long-term follow-up.
BACKGROUND
Only a few cases have been previously published about clear cell meningiomas in children, the majority of them in the location of the spine. We describe an unusual case of clear cell meningioma occurring at the petro-clival region in a 5-year-old child. We further seek to determine the impact of several growth factors as well as the AKT1 mutation on the tumor growth pattern.


CASE PRESENTATION
A five-year-old girl was presented with a one-week history of cephalgia, ataxia, and left sided torticollis. Magnetic resonance imaging (MRI) revealed a dumbbell-shaped homogeneously petro-clival gadolinium-enhancing mass. A staged operative approach was chosen, and a complete removal of the tumor was achieved. Due to recurrent tumor progression, the child underwent several tumor surgeries and two cranial radiations. None of the treatments were able to stop tumor progression. Consequently, the child died at the age of 14 after further extensive intracranial and extracranial tumor progression. The initial histological examination revealed a clear cell meningioma WHO grade II with an MIB-1 labeling index of <1%, which gradually increased with every recurrence up to 10% by the last progression at the age of 13 years. Analogically, an increasing overexpression of epidermal growth factor receptor (EGFR), the platelet-derived growth factor receptor (PDGFR), and the vascular endothelial growth factor receptor (VEGFR) was observed with each recurrence. The AKT1 (E17K) mutation in the tumor was not detectable in all investigated specimens.


CONCLUSION
Pediatric clear cell meningiomas WHO grade II are very rare. Our data demonstrate the progressive overexpression of EGF-, PDGF-, and VEGF-receptors in each recurrence, providing one of these receptors as targeted therapy in such cases. Further evaluation of these growth factors in clear cell meningioma is required to establish the optimal treatment of these aggressive tumors.
['Juratli|Tareq A|TA|', 'Geiger|Kathrin D|KD|', 'Weigel|Patrick|P|', 'von der Hagen|Maja|M|', 'Daubner|Dirk|D|', 'Pinzer|Thomas|T|', 'Hahn|Gabriele|G|', 'Schackert|Gabriele|G|', 'Kirsch|Matthias|M|']
D001921:Brain D002675:Child, Preschool D066246:ErbB Receptors D005260:Female D006801:Humans D008137:Longitudinal Studies D008279:Magnetic Resonance Imaging D008577:Meningeal Neoplasms D008579:Meningioma D009154:Mutation D051057:Proto-Oncogene Proteins c-akt D020796:Receptor, Platelet-Derived Growth Factor alpha D040262:Receptors, Vascular Endothelial Growth Factor
Child Clear cell meningioma AKT1 mutation Platelet-derived growth factor receptor Vascular endothelial growth factor receptor Epidermal growth factor receptor