Pathological features determining recurrence and radioresistance in cerebral atypical meningioma

We examined recurrence after gross total resection (GTR) or subtotal (STR) at St. Michael’s Hospital, Toronto, of 181 cases atypical meningioma (WHO grade II). In the entire group, Kaplan-Meier survival curves showed that combined necrosis and brain invasion was feature associated with worst outcome, followed in order by necrosis, histological variants (clear cell, rhabdoid, chordoid), high mitotic count, invasion. The highly significant difference between seen only patients receiving GTR, lost those treated STR. Adjuvant radiotherapy worse more so GTR. presence count (defined as >4/10HPF) radiation did not affect recurrence, but specially magnified apparent deleterious effect adjuvant radiotherapy. invasion, radiotherapy’s small reach significance. Since were randomized to radiotherapy, these results should be construed indicating this treatment is injurious. It can stated particularly alone, meningiomas are resistant any possible beneficial delaying recurrence. LEARNING OBJECTIVES This presentation will enable learner to: 1. Describe factors determining meningioma. 2. List radioresistance