[Comparative analysis of Grade I vs Grade II intracranial Meningiomas in a retrospective series of 63 patients].

Objective: We aimed to demonstrate the differences between grade I and II (OMS classification) of intracranial meningiomas. We evaluate their location, Simpson resection grade, re-operations rate, adjuvant treatment and patient outcomes.

Methods: We conduct a retrospective review of Sixty- three clinical records of patients who were diagnosed with meningiomas grade I and II (OMS) between 2009-2015 and received surgical treatment at our Hospital. We evaluated different variables such as age, sex, histological type, Simpson grade resection, location, symptoms, radiotherapy, follow-up, mortality rate and patient outcome. The main aim was to establish the differences between these intracranial tumors.

Results: A total of sixty-three patients diagnosed with meningiomas and received surgical treatment; fifty-one were grade I and thirteen with grade II. There were no differences in the rate between man and women. The average age for both types of meningiomas was 57 years old. The typical meningiomas were located in 55% of the cases outside the cranial base vs. 91.6% of the atypical meningiomas ( P = 0.03). Typical meningioma had a Simpson resection grade of I, II and III in 74.5% against 58.3% of the atypical ( P = 0.2). The atypical meningioma in 33% had more than one-stage surgery vs. 9.8% of the typical ( P = 0.03). The patients with a typical meningioma showed a good outcome in 86.2% vs. 53.8 of the grade II ( P = 0, 01). The typical meningiomas showed a good outcome in 82.2% of the cases vs. 53.8% of the atypical. The grade II meningiomas received adjuvant treatment in 33.3%, while the grade I only 1.9%.

Conclusions: The atypical intracranial meningiomas have a worse outcome compared with the typical kind and a higher incidence of re-operations. These tumors have a preference for a location outside the cranial base. Concluding that the location could be a risk factor.