Primary and metastatic pulmonary meningioma.
Patient 1 was a 53-year-old man who had a very rare primary pulmonary meningioma that developed in the left lingular segment. When this report was written, 7 years had passed since he underwent operation, and no recurrence of the meningioma had been detected. In Patient 2, a 61-year-old woman, multiple pulmonary metastases were confirmed 19 years after she had undergone operation for multiple cerebellar meningiomas, and the metastases were resected. After 2 years, multiple intraperitoneal metastases were found, and thus aggressive surgery was performed. Currently, 22 years after the operation for the primary cerebellar meningioma, the patient is alive without any subjective symptoms, although intraperitoneal metastases have recurred. To date, only four cases (all in women) of primary pulmonary meningioma have been reported. Case 1 reported in this article is thus the first case in a male patient to be reported, and, in addition, this patient also has the first reported case to have been evaluated for more than 5 years. In Case 2, however, each of the excised extracranial tumor lesions was histologically homogeneous and showed a hemangiopericytomatous pattern. The histologic picture of those tumor lesions was exactly the same as the picture of a small portion of the cerebellar meningiomas excised 19 years earlier. Thus, all those extracranial tumor lesions were diagnosed to be metastatic meningiomas. However, it is difficult to explain why there had been no symptoms for as long as 19 years until the pulmonary metastases were discovered.