Meningioma of the paranasal sinuses. A report of two cases.

Two patients presented with primary meningiomas arising in the paranasal sinuses. Despite nonspecific symptoms, both patients had extensive local clinical disease. One patient had a lateral rhinotomy with total removal of tumor; he has remained well for 3 years. The second patient, who was not a surgical candidate because of her cerebrovascular disease, was identified retrospectively. Her tumor was not originally studied using current day morphologic methods. She was irradiated following a diagnosis of malignant tumor. The histologic features of nasal meningioma are similar to those of conventional intracranial lesions, including nuclear pseudoinclusions. Although the unusual location may suggest carcinoma, melanoma, or olfactory neuroblastoma, adjunctive use of electron microscopy and immunohistochemistry can be combined to arrive at the correct diagnosis.