Intracranial Meningioma as Initial Clinical Manifestation of Occult Lung Carcinoma: Case Report

Abstract

Intracranial meningioma with intratumor metastasis have been occasionally reported. However, to our knowledge, there are almost no reports of malignant tumors initially discovered due to metastasis to meningioma. A 74-year-old woman presented with amnesia. Magnetic resonance imaging showed a well-defined mass arising from falcotentorial junction and homogeneous enhancement. Histopathologic findings showed that the mass was a meningothelial meningioma, with the majority of the tumor cells propagating in sheets, however, a single area in the tumor tissue showed the different histology. Immunohistologically, cytokeratin 7 (CK7), thyroid transcription factor-1 (TTF-1), and Napsin were positive, which led to lung adenocarcinoma metastasis. Furthermore, E-cadherin staining showed a 70% positive rate in lung adenocarcinoma and 30% in meningothelial meningioma. We report our experiences regarding a case of lung cancer that metastasized to intracranial meningioma and its clinical presentation and pathology.