Adrenal metastasis of anaplastic meningioma: report of a rare case

Meningiomas are the most common primary extra-axial tumours of the central nervous system, however their metastatic spread beyond central nervous system is rare. Here we present the case of a 54-year-old male with anaplastic meningioma who, 1.5 years after initial diagnosis, developed a tumorous expansion in his left adrenal gland, showing octreotide uptake on scintigraphy. Clinical diagnosis of pheochromocytoma was made and left adrenalectomy performed. The tumour weighed 480 grams and measured up to 140 mm in diameter. On histologic examination, morphology consistent with the diagnosis of anaplastic meningioma was present, resembling the original central nervous system tumour. The tumour expressed strongly SSTR2A and focally epithelial membrane antigen, p63 and pancytokeratin (AE1/3). An extensive panel of neuronal and additional epithelial markers (SOX10, synaptophysin, chromogranin, inhibin, calretinin, BER-EP4, MOC31) was negative. The review of the literature on meningioma metastasising outside the central nervous system and on its differential diagnosis is provided.