Long-Term Prognostic Impact of the Dural Tail in the Local Control of Intracranial Meningiomas

Introduction: The dural tail is a thickening of the dura adjacent to an intracranial pathology, mostly related to meningiomas. The prognostic impact of the dural tail sign has been a debate since the last century, and most surgeons consider that the completeness of a meningioma resection depends on the resection of the dura mater invaded by the tumor. On the other hand, some histological studies support that this dural thickening does not contain tumor cells, and even including it in the radiation fields may not improve the prognostic outcomes. Moreover, the majority of the studies do not provide long-term follow-ups. In this study, we analyze our cohort of meningiomas to determine the role of the dural in the prognosis of the disease.

Methods: We retrospectively reviewed all patients with meningiomas treated with surgery between 2000 and 2015. We determine this period in order to guarantee at least 5 years of follow-up. Patients receiving postoperative radiation were excluded. We analyzed different features of the dural tail and correlated them to the tumor grade and the extent of resection.

Results: A total of 125 patients were analyzed. The mean age was 50 years old, with a female prevalence of 4:1. Convexity and parasagittal meningiomas represent half of the patients (49.6%, n = 62) and 32%, respectively. More than 80% of the cases were meningiomas WHO grade 1 (n = 102), and complete resection including the dural tail was achieved in 50.4% (n = 63). In terms of the dural tail, we defined three radiologic subtypes ([Fig. 1]). Smooth, nodular, and mixed types were the features present in 100 (80%), 6 (4.8%), and 19 (15.2%) of the cases, respectively. Regarding the follow-up period, the median was 108.4 months ([Fig. 3A]) (IQR 81.5–158.9), and the crude recurrence rate was 16% after a median of 50 months ([Fig. 2], bottom table). None of the radiologic subtypes of dural tail showed a prognostic impact ([Fig. 3B]; p = 0.542) or a significant correlation with a higher grade of meningioma ([Fig. 3D]). Nevertheless, avoiding the resection of the dural tail has shown a detrimental impact on progression-free survival, with a 10-year PFS of 75% compared to 92% in those patients with a complete resection including the surrounding dural rim (HR = 2.72, CI = 1.13–6.56; p = 0.029) ([Fig. 3C]). This positive correlation could not be replicated on a multivariate COX-regression analysis (p = 0.32). ([Fig. 4]).

Conclusions: We present a large cohort of patients with a minimum of five years of follow-up. According to our results, there is a significant prognostic impact with the resection of the dural tail, and this result has to be replicated in other series with longer follow-up periods. This study demonstrates that the dural thickening surrounding meningiomas is still controversial and needs to be studied thoroughly.

Publication History

Article published online:
05 February 2024