Mitotic Index is an Independent Predictor of Recurrence-Free Survival in Meningioma

作者：Olar Adriana^*; Wani Khalida M; Sulman Erik P; Mansouri Alireza; Zadeh Gelareh; Wilson Charmaine D; DeMonte Franco; Fuller Gregory N; Aldape Kenneth D

来源：Brain Pathology, 2015, 25(3): 266-275.

DOI：10.1111/bpa.12174

• meningioma
• mitotic index
• pHH3
• recurrence-free survival

While World Health Organization (WHO) grading of meningioma stratifies patients according to recurrence risk overall, there is substantial within-grade heterogeneity with respect to recurrence-free survival (RFS). Most meningiomas are graded according to mitotic counts per unit area on hematoxylin and eosin sections, a method potentially confounded by tumor cellularity, as well as potential limitations of accurate mitotic figure detection on routine histology. To refine mitotic figure assessment, we evaluated 363 meningiomas with phospho-histone H3 (Ser10) and determined the mitotic index (number of mitoses per 1000 tumor cells). The median mitotic indices among WHO grade I (n=268), grade II (n=84) and grade III (n=11) tumors were 1, 4 and 12. Classification and regression tree analysis to categorize cut-offs identified three subgroups defined by mitotic indices of 0-2, 3-4 and5, which on univariate analysis were associated with RFS (P<0.01). In multivariate analysis, mitotic index subgrouped in this manner was significantly associated with RFS (P<0.01) after adjustment for Simpson grade, WHO grade and MIB-1 index. Mitotic index was then examined within individual WHO grade, showing that for grade I and grade II meningiomas, mitotic index can add additional information to RFS risk. The results suggest that the use of a robust mitotic marker in meningioma could refine risk stratification.

• 出版日期2015-5