Intracranial plasma cell-granuloma with extensive ossification.

Intracranial plasma-cell granuloma is non-neoplastic proliferation of plasma cells which occurs rarely. We present an unusual case of an 18-year-old female patient with extensively ossified intracranial plasma-cell granuloma. Computed Tomography (CT) and Magnetic Resonance Image (MRI) demonstrated a left frontoparietal mass with extensive calcification. The lesion was removed subtotally. Histopathological findings revealed diffuse inflammatory cells consisting mostly of reactive plasma cells, histiocytes and neutrophils, several lymphocytes, lymphoplasmacytic cells, a few eosinophils throughout the dura and adjacent brain. Widespread psammomatous and dystrophic calcifications, and very extensive ossification with trabecular bone formation were present within the lesion. In the case of an intracranial mass lesion with calcification, plasma-cell granuloma, although rare, should be included in the differential diagnosis.