Assessment of hemorrhagic onset on meningiomas: Systematic review

Objective: To review the data published on the subject to create a more comprehensive natural history of the haemorrhagic onset of meningiomas (IVMs). Patients and methods: A Medline search up to June 2020, using the search term "bleeding meningioma," returned 136 papers. As a first selection step, we adopted the following inclusion criteria: series and case reports about bleeding meningioma. Papers written in other languages but with abstracts written in English were also evaluated. Results: A total of 190 tumours were evaluated, specifically 109 tumours from female patients and 81 tumours from male patients with a ratio of 1.34 female to 1.0 male (mean age of 54.86 16.1years old). The majority were located in the convexity (129-67.9 %). Among the 190 tumours evaluated, 171 patients (90 %) presented with GI tumours, with a predominance of the meningothelial subtype (32.6 %). Nine patients (4.7 %) presented with grade GII tumours, and 10 (5.3 %) presented with GIII tumours. The most prevalent type was intracerebral haemorrhage (ICH) at 50 %, followed by subdural at 27.36 %; the mortality rate was 13.1 % (25 deaths), the distribution of both location (prevalence of convexity: 18-72 %) and histopathology (grade 1: 22-88 %). Conclusion: These tumours follow the histopathological distribution of meningiomas, in general. The age distribution shows prevalence among the adult population but with a greater proportion in the elderly. The fact that the overwhelming majority of cases involve meningiomas with a benign histological subtype is noteworthy. Another relevant factor observed is that most reports are from Asian origin.