Apoptotic activity and bcl-2 immunoreactivity in meningiomas - Associationwith grade and outcome

We retrospectively evaluated 90 meningiomas for bcl-2 expression, apoptosis counts (per 10 high-power fields [HPF]), MIB-1 labeling indices (LI), nad mitosis counts (per 10 HPF). Characteristics were as follows: 37 low-grade (benign) meningiomas: mean apoptosis count, 1.2; MIB-1 L1, 1.0; mitosis cou nt, 0.1; and bcl-2 positivity 40%, 29 atypical meningiomas: apoptosis count , 3.3; MIB-1 LI, 5.5; mitosis count, 2.2: and bcl-2 positivity, 62%; 24 mal ignant meningiomas: apoptosis count, 6.5; MIB-1 LI, 12.0; mitosis count, 6. 0; and bcl-2 positivity, 67%. By univariate analysis, MIB-1 LI., apoptosis and mitosis counts, and tumor grade were associated significantly with deat h due to tumor; by multivariate analysis, only mitosis count was independen tly associated with death due to tumor: We compared similar data for 27 pat ients with nonrecurrent tumors and 32 patients with recurrent meningiomas. Histologic sections from the initially resected turner and from the most re cent recurrence were reviewed. Only the apoptosis count was significantly h igher by univariate analysis in the initial resection specimens from tumors that ultimately recurred vs nonrecurrent tumors. Expression of bcl-2, MIB- 1 LI, and mitosis count did not correlate with recurrence. By multivariate analysis, only extent of surgical resection was associated significantly wi th tumor recurrence. Although bcl-2 immunostaining was nut associated stati stically with outcome, bcl-2 positivity was more common in atypical and mal ignant meningiomas than in low-grade turners.