1. AANP: Diagnostic Slide Session – Case 04 Tracie Pham, M.D., William H. Yong, M.D., Gary W. Mathern, M.D., and Harry V. Vinters, M.D. UCLA Department of Pathology and Laboratory Medicine, Division of Neuropathology, and Department of Neurosurgery

2. Clinical History 13 year-old male who presents with complex partial seizures since age 6 years Initially managed on Trileptal, with Keppra added in 2005; currently on Lamictal History of NF1, diagnosed at age 18 months due to presence of café-au lait skin lesions and neurofibromas

3. Radiologic Studies PET scan on 6/22/10: Small focus of hypometabolism in the right frontal lobe MRI scan on 9/30/10: Stable cortically- based lesion in the right anterior frontal convexity with small multifocal enhancement, small cystic foci and no perilesional edema. Stable small foci of T2W hyperintensity in the cerebrum.

4. MRI of Brain Scan 9/30/10 Image courtesy of Hassana Ibrahim, M.D.

5. MRI of Brain Scan 9/30/10 Image courtesy of Hassana Ibrahim, M.D.

6. MRI of Brain Scan 9/30/10 Image courtesy of Hassana Ibrahim, M.D.

15. Smooth Muscle Actin

18. GFAP

19. Neurofilament

20. NeuN

21. Final Diagnosis Meningioangiomatosis Focus consistent with ganglioglioma (predominantly ganglion cells), WHO grade I

22. Diagnostic Points Both meningioangiomatosis (MA) and ganglioglioma can present with seizures Meningioangiomatosis associated with NF2 (in this case, patient had NF1) Tissue sampling is critical – focus of ganglioglioma only on one section Smooth muscle actin helpful in highlighting the microvascular component and smooth muscle cell proliferation of MA; interesting SMA immunoreactivity in cells with neuronal phenotype

23. References Prayson RA. Tumours arising in the setting of paediatric chronic epilepsy. Pathology 2010; 42(5): 426-431 Stemmer-Rachamimov AO, Horgan MA, Taratuto AL, Munoz DG, Smith TW, Frosch MP et al. Meningioangiomatosis is associated with neurofibromatosis 2 but not with somatic alterations of the NF2 gene [Review]. J Neuropathol Exp Neurol 1997; 56: 485-489 Vinters HV. Pediatric Vascular Malformations. In: Pathology and Genetics. Developmental Neuropathology. Golden JA and Harding BN (eds). Basel: ISN Neuropath Press; 2004, pp. 116-124 Wiebe S, Munoz DG, Smith S, and Lee DH. Meningioangiomatosis: A comprehensive analysis of clinical laboratory features. Brain 1999; 122: 709-726