MAC-spinal meningioma score: A proposal for a quick-to-use scoring sheet of the MIB-1 index in sporadic spinal meningiomas

ObjectiveMIB-1 index is an important predictor of meningioma progression. However, MIB-1 index is not available in the preoperative tailored medical decision-making process. A preoperative scoring sheet independently estimating MIB-1 indices in spinal meningioma (SM) patients has not been investigated so far. MethodsBetween 2000 and 2020, 128 patients with clinical data, tumor imaging data, inflammatory laboratory (plasma fibrinogen, serum C-reactive protein) data, and neuropathological reports (MIB-1, mitotic count, CD68 staining) underwent surgery for spinal WHO grade 1 and 2 meningioma. ResultsAn optimal MIB-1 index cut-off value (>= 5/<5) predicting recurrence was calculated by ROC curve analysis (AUC: 0.83; 95%CI: 0.71-0.96). An increased MIB-1 index (>= 5%) was observed in 55 patients (43.0%) and multivariable analysis revealed significant associations with baseline Modified McCormick Scale >= 2, age >= 65, and absence of calcification. A four-point scoring sheet (MAC-Spinal Meningioma) based on Modified McCormick, Age, and Calcification facilitates prediction of the MIB-1 index (sensitivity 71.1%, specificity 60.0%). Among those patients with a preoperative MAC-Meningioma Score >= 3, the probability of a MIB-1 index >= 5% was 81.3%. ConclusionThis novel score (MAC-Spinal Meningioma) supports the preoperative estimation of an increased MIB-1 index, which might support preoperative patient-surgeon consultation, surgical decision making and enable a tailored follow-up schedule or an individual watch-and-wait strategy.

Automated summary

This study investigated a preoperative scoring sheet for estimating the MIB-1 index in patients with spinal meningioma. Multivariable analysis revealed significant associations between the baseline Modified McCormick Scale, age, calcification, and an increased MIB-1 index. A four-point scoring sheet (MAC-Spinal Meningioma) was developed to predict the increased MIB-1 index. This scoring sheet can be used for preoperative patient-surgeon consultation, surgical decision-making, and individualized follow-up or watch-and-wait strategies.