Meningioma in shape: Can the appearance of tumour margins be considered as a prognostic factor?

Objective: The aim of this study was to evaluate the possible relationship between the appearance of tumour margins of atypical meningiomas and the risk of tumour recurrence, as well as progression-free survival. We also evaluated the correlations between the tumour margins and the neuroimaging characteristics (e.g. brain oedema and contrast enhancement) along with pathological features (e.g. brain invasion and mean value of Ki-67 LI). Material and methods: In our study, we included 81 patients diagnosed with atypical meningioma (grade II meningioma), who have undergone surgery at the "Prof. Dr N. Oblu" Emergency Clinical Hospital Iasi, between January 1, 2010, and December 31, 2019. We followed the MRI imaging characteristics (e.g. tumour margins patterns, contrast enhancement, oedema grading and tumour volume), but also the pathological characteristics such as brain invasion and the mean value of the Ki-67 labelling index. The assessment of tumour recurrence was made using MRI imaging (T1+ contrast), over a follow-up period of 5 years after the surgery. Results: In our study, we observed that 59.3% (n=48) of meningiomas had an irregular appearance. The irregular margins predominated in the male population (65.1%) and were statistically significantly correlated with brain oedema (p