Descriptive epidemiology of 30,223 histopathologically confirmed meningiomas in France: 2006-2015

Meningioma is one of the most common neoplasm of the central nervous system. To describe the epidemiology of meningioma operated in France and, to assess grading and histopathological variability among the different neurosurgical centres.

We processed the French Brain Tumour Database (FBTDB) to conduct a nationwide population-based study of all histopathologically confirmed meningiomas between 2006 and 2015.

30,223 meningiomas cases were operated on 28,424 patients, in 61 centres. The average number of meningioma operated per year in France was 3,022 (SD ± 122). Meningioma was 3 times more common in women (74.1% vs. 25.9%). The incidence of meningioma increased with age and, mean age at surgery was 58.5 ± 13.9 years. Grade 1, 2, and 3 meningiomas accounted for 83.9%, 13.91% and, 2.19% respectively. There was a significant variability of meningioma grading by institutions, especially for grade 2 which spanned from 5.1% up to 22.4% (p < 0.001). Moreover, the proportion of grade 2 significantly grew over the study period (p < 0.001). There was also a significant variation in grade 1 subtypes diagnosis among the institutions (p < 0.001). 89.05% of the patients had solely one meningioma surgery, 8.52% two and, 2.43% three or more. The number of surgeries was associated to the grade of malignancy (p < 0.001).

The incidence of meningioma surgery increased with age and, peaked at 58.5 years. They were predominantly benign with meningothelial subtype being the most common. However, there was a significant variation of grade 1 subtypes diagnosis among the centres involved. The proportion of grade 2 meningioma significantly grew over the study time, on contrary to malignant meningioma proportion, which remained rare and, stable over time around 2%. Likewise, there was a significant variability of grade 2 meningioma rate among the institutions.