Radiologic and Histopathologic Features in an Intracranial Localized Castleman Disease

Abstract

Castleman disease (CD) is a rare pathologic process of unknown etiology, characterized by non-neoplastic lymph node enlargement. Two distinct histologic patterns are recognized; the hyaline-vascular type and the less common plasma cells type. Another intermediate type has been described. The clinical features are classified into 2 categories, localized (unicentric) and generalized (multicentric), the later associated with systemic manifestations and poor prognosis. CD affecting the central nervous system is extremely rare. We report a new case of localized intracranial CD and we accomplish a review of the literature. A 30-year-old man presented with a generalized tonic-clonic seizure. Computerized tomography and magnetic resonance imaging showed a small mass in the right temporoparietal convexity with homogenous enhancement after contrast administration. Extensive vasogenic edema in comparison with the size of the mass was also identified and based on the neuroradiologic finding, a suspected diagnosis of meningoangiomatosis was formulated. The mass was completely resected and his histologic examination identified the hyaline-vascular type of CD. One year after surgery, the patient remains seizure free, without evidence of systemic involvement or recurrence of the mass. Our case and review of the literature show the value of the extensive brain edema on neuroimaging finding to the differential diagnosis for a solitary mass arising from the meninges. We emphasize on the need for histologic examination when the diagnosis of meningioma is not entirely clear.