Concurrent Pulmonary Metastasis as an Initial Presentation from a Benign Meningioma: A Case Report and Literature Review

Extracranial metastases from meningioma rarely occurs, less than 0.1% of cases. The most common site is lung, followed by bone and liver. Most of the cases were presented in atypical or anaplastic meningiomas, usually after receiving one or more surgical procedures.

A 51-year-old male patient visited an ophthalmologic clinic due to decreased vision in the left eye. His exams showed papilledema in both eyes and was referred to our ER for IICP evaluation. On physical examination, his cranium showed asymmetric disfiguration which aggravated for 2 years. His brain CT and MRI revealed an extensive convexity meningioma in the fronto-parietal area accompanied with massive hyperostosis ([Fig. 1]). During preoperative evaluation, the patient showed a 3 × 2 cm sized nodular lung mass in right lower lobe. Radiologic impression was lung cancer or benign tumor such as sclerosing pneumocytoma.

For symptom control, surgery for the brain lesion was performed first. Tumor embolization was preceded, and the tumor was totally removed including the cranium with hyperostosis. The tumor abutting the superior sagittal sinus was also removed and the thickened sinus walls were coagulated (Simpson grade II). Afterwards, the patient received wedge resection for the lung mass. The pathologic results showed meningothelial meningioma, for both the brain and lung lesions.

Only three cases of concurrent lung metastases were reported in the literature as an initial presentation. There is also a single case reported that lung metastasis was detected prior to the brain lesion itself. Among the proposed mechanisms that have been possible routes for metastases, our case shows that hematogenous dissemination can happen even in lower grade tumors. Moreover, although we cannot be definitive about the factor yet, we had the impression that marked invasiveness such as the degree of bone invasion could also contribute to extracranial metastases. Further studies to define the causative factors of extracranial metastases for meningiomas are warranted.

Fig. 1