Histopathologic features predicting recurrence of meningiomas following subtotal resection.

Histopathologic features that predict recurrence of meningiomas following subtotal resection were identified by reviewing the initial surgical specimens from 82 patients (38 with tumor recurrence and 44 without) treated at the Massachusetts General Hospital between 1962 and 1984. There was no correlation between histologic subtype and tendency toward tumor recurrence; however, the few examples of hemangiopericytoma, angioblastic meningioma, or sarcomatous meningioma were observed almost exclusively in patients with recurrent tumors. Seven histopathologic features were positively correlated with recurrence of meningiomas, including the following: hypervascularity of tumors, hemosiderin deposition, growth of tumor cells in sheets rather than the usual growth patterns of meningiomas, prominent nucleoli, mitotic figures, single-cell and small-group necrosis, nuclear pleomorphism, and overall atypical or malignant tumor grade (all p less than 0.005). In addition, sheeting of tumor cells, prominent nucleoli, and the presence of less than 10% meningothelial pattern were correlated with significantly abbreviated progression-free survival, i.e., more rapid progression of tumor with shorter intervals between treatment and tumor recurrence. These findings suggest that the presence of features such as large prominent nucleoli, tumor growth in sheets, individual-cell necrosis, and nuclear pleomorphism may be used to predict recurrence of subtotally resected meningiomas that would not be classified as malignant by traditional criteria.