Meningioma recurrence

In Intracranial meningioma surgery, resection is considered to be the most important therapeutic step to avoid meningioma recurrence. However, resection of skull base lesions with orbital or optic nerve involvement poses a challenge due to their anatomical structure and their proximity to eloquent areas.

Risk of recurrence

There are four critical histopathological variables that affect the rate of meningioma recurrence:

1. Meningioma grade

2. Meningioma histological subtype

3. Meningioma proliferation index

4. Brain invasion (see Brain invasion in atypical meningioma).

The presence of brain invasion increases the likelihood of recurrence to levels similar to atypical meningiomas (not anaplastic), ¹⁾ but is not an indicator of malignant grade. Brain invasion in atypical meningiomas does not dictate malignant behavior. Adding the phrase “with brain invasion” is suggested to denote a higher risk of recurrence ²⁾

Tumor recurrence remains the major clinical complication of meningiomas, the majority of recurrences occurring among WHO grade I/benign tumors.

The MIB-1 index was evaluated as a possible predictor of meningiomas with a higher risk of recurrence ³⁾.

Domingues et al, found an adverse impact on patient relapse-free survival (RFS) for males, presence of brain edema, younger patients (<55 years), tumor size >50 mm, tumor localization at intraventricular and anterior cranial base areas, WHO grade II/III meningiomas, and complex karyotypes; the latter 5 variables showed an independent predictive value in multivariate analysis. Based on these parameters, a prognostic score was established for each individual case, and patients were stratified into 4 risk categories with significantly different (P < .001) outcomes. These included a good prognosis group, consisting of approximately 20% of cases, that showed a RFS of 100% ± 0% at 10 years and a very poor-prognosis group with a RFS rate of 0% ± 0% at 10 years. The prognostic impact of the scoring system proposed here was also retained when WHO grade I cases were considered separately (P < .001) ⁴⁾.