The dural tail in intracranial meningioma: Heads up or tail down? A systematic review of the literature.

Meningiomas are the most common primary intracranial tumours. Recurrence occurs in up to 20%, with even higher percentages in atypical or malignant meningiomas. The non-removal of the dural tail may be a risk factor for recurrence. In this review, we aimed to determine the prevalence of tumour tissue in the radiological dural tail sign. Our secondary outcome was to determine the clinical relevance of the dural tail, if possible. PubMed, Embase, ISI Web of Science and the Cochrane Library were systematically searched for studies. Articles evaluating dural tails with both radiological and histopathological findings were included. Two reviewers independently screened studies. Data was extracted manually. 18 articles met the inclusion criteria out of 843 identified reports. In total, 406 patients with a radiological and histopathological evaluated dural tail were found. 286 patients (70.9%) had tumour infiltrate; 110 non-neoplastic dural tails showed vascular changes, loose connective tissue proliferation or inflammation. 65 patients with seemingly normal dura mater were reported, of which 26 (40.0%) showed tumour infiltration. It appears that tumour tissue in the radiological dural tail is common. Concerningly, approximately 40% of non-enhancing dura also revealed tumour tissue in the pathological examination. This highlights the need for further systematic research into the dural tail and its clinical impact on recurrence. Clinical trial number Not applicable.