Evaluation of Resection Margin after Image-Guided Dural Tail Resection in Convexity Meningiomas

Infiltration of adjacent dura with meningioma cells is a common phenomenon. Wide resection of the dural tail (DT) to achieve a gross total resection is a general recommendation. We aimed to investigate a tumor cell infiltration of the DT after image-guided resection of convexity meningiomas. The study's inclusion criteria were the diagnosis of convexity meningioma, planned Simpson I° resection, and an identifiable DT. Intraoperative image-guidance was applied to identify the outer edge of the DT and to guide resection. After resection, en-bloc specimen or four samples of outermost pieces of DT in case of piecemeal resection were sent for histological analysis. In addition to resection margin infiltration, the radiological extent of DT, radiomic characteristics (109 in total), histology, and demographic data were assessed. Hierarchical clustering was used to generate patient clusters for radiomic analysis. Twenty-two patients were included in the study, while 20 (91%) were female. The mean age was 54.2 (Standard deviation (SD) 13.9, range 30-85) years. En-bloc resection could be achieved in 4 patients. The remaining patients received piecemeal resection. 2 DT samples were omitted due to tumor infiltration of the superior sagittal sinus. None of the en-bloc resection samples demonstrated dural infiltration on the resection margin. Tumor cells were detected in 4 of 70 (5.7%) dural tail samples and could not be excluded in another 5 of 70 (7.1%). No tumor recurrences were detected at follow-up MRI examinations after a mean follow-up of 27.5 (SD 13.2, range 0 to 50.0) months. There was no significant association between DT infiltration and histological subtype or patient characteristics and between DT extent and tumor infiltration. Clustering according to radiomic characteristics was not associated with tumor infiltration (p = 0.89). The radiological dural tail does not reliably outline the extent of tumor cell infiltration in convexity meningiomas. Hence, the extent of dural tail resection should not exclusively be guided by preoperative radiological appearance.