Recurrence of Anterior Skull Base Meningioma after Endoscopic Endonasal Resection. Retrospective Review of a Series of 28 Cases over Ten Years

Introduction: While the advantages and complications of the expanded endoscopic endonasal (EEE) approach for the removal of olfactory groove (OGM) and tuberculum sellae & planum (TSM) are known, there is little data on the long term recurrence rates.

Objectives: After a review of the previously published series, we report the recurrent cases in our series trying to identify predictors of recurrence. We report on and attempt to correlate pre- and postoperative imaging, operative technique (extent of resection) and pathology (tumor grade), which may be related to recurrence.

Material and Methods: Twenty-eight cases, (6 OGM and 22 TSM), operated on between May 2006 and December 2015 were retrospectively reviewed with special emphasis of the recurrence.

Results: In our series gross total resection (GTR) was achieved in 4/6 OGM (60%) and 15/22 (68%) TSM patients. The mean follow up was 29 months. Among these 28 patients, 4 (14.2%) presented with a recurrence; 2 cases (1 OGM, 1 TSM) of regrowing residual tumor and 2 (1 OGM, 1 TSM) cases of recurrence after total resection. All of them had WHO grade I lesions. One patient (OGM) had undergone a prior resection of an intracranial component by transcranial approach 8 years before. All of these 4 cases did not experience any postoperative complication and recurred respectively at 40, 29, 41, and 19 months following the EEE approach, with a mean time of 32 months. One patient underwent an open approach for the recurrence and a second patient is to undergo stereotactic radiation.

Conclusion: The potential for recurrence of anterior skull base meningiomas operated upon with an endoscopic endonasal approach is yet not well known. This report has shown a 14% early recurrence after EEE. This will have to be compared with recurrence rates in transcranial approaches. However further studies with longer follow up of patients are needed to provide a more meaningful analysis. This data could allow refinement of the operative technique and better understanding of the limitations of the expanded EEE approach to anterior skull base meningiomas.