A quest towards personalised medicine for grade II meningiomas—will need to zoom in

Abstract

In the end, 206 cases were included in the study and only two patients were lost to follow-up. The median follow-up was 4.1 years, with the interquartile range of 1.6-7.3 years.Overall survival probabilities at 1, 5 and 10 years were respectively: 95, 84 and 73 %-easy numbers to remember. Even based on the relatively low numbers, the 95 %-confidence intervals are fairly tight: 93-98, 78-90, and 65-82 %, respectively. When the 5-year overall survival of the Glasgow cohort is viewed in the context of other series (Table 3) [2], it seems that 5-year survival of surgically treated atypical meningiomas ranges from approximately 75-90 % (an apparent outlier series put aside).Univariate analysis of the cohort revealed age, Simpson grade, presence of brain invasion, venous sinus invasion, tumour volume and reoperation to be associated with survival. These variables were then entered into the Cox multivariate regression model, which identified age (62 years and lower), Simpson resection grade (grades 1-3 versus 4-5) and absence of brain invasion as predictors of longer overall survival.Although questioned by some [14], Simpson grade remains a powerful determinant of prognosis for meningiomas, including atypical meningiomas. In fact, along with our anecdotal observation, Gousias et al. [5] found in their series of 901 consecutive meningioma resections that the influence of Simpson grade on progression-free survival (PFS) was even greater in grade II and III than grade I meningiomas.Radiotherapy was not a factor predictive of survival, even in the univariate model. The specific role of adjuvant radiotherapy for individual tumours remains unclear and has not been rigorously assessed in the existing literature [11,12]. For grade II meningioma, two phase-2 dose-escalation studies by the EORTC and RTOG are due to report soon and the upcoming ROAM/EORTC 1308 trial will address the role of early radiotherapy following gross total resection [6]. Not surprisingly, at least for now, meningiomas remain a Bsurgical^disease with regards to their treatment.Brain invasion was the basis of the last modification of the meningioma grading published in the in the 2007 edition of the WHO classification of the tumours of the central nervous system [10]. In the 1993 classification, when atypical meningioma was first introduced, brain invasion was a feature that automatically upgraded the tumour to an anaplastic category [8]. The next edition, the 2000 WHO classification [7], saw major changes introduced to the grading of meningiomas. The previously vague histological descriptions were tightened up with explicitly defined mitotic rates for each grade. Brain invasion in the context of otherwise benign histological