Recurrent and atypical meningiomas--a multiparametric study using Ki67 labelling index, AgNOR and DNA Feulgen staining.

OBJECTIVE

Histological analysis has limited value to predict the biological behavior of meningiomas. In this study, we investigated the utility of indicators of cell proliferation in the evaluation of histologically benign meningiomas.

MATERIALS AND METHODS

For this purpose, 50 meningothelial meningiomas, 50 atypical meningiomas and 8 primary benign meningiomas with their recurrences were studied. For each case the Ki67 labeling index (LI), DNA ploidy and AgNOR were evaluated and the results quantitatively processed and assessed by computerized image analyzer.

RESULTS

The Ki67 labelling showed a low index (11.3%) in typical meningiomas and primary meningiomas (13.6%). In contrast, it was higher in atypical (26.6%) and recurrent meningiomas (28%). Similar results were obtained for the AgNOR granule count which showed that typical and primary meningiomas had mean 1.51 - 1.49, whereas recurring meningiomas and atypical meningiomas had mean values of 1.92 and 1.98, respectively. DNA ploidy revealed in the hyperpolyploid region between 4c - 16c: 7.02% of the nuclei in primary meningiomas, 17.98% of the nuclei in recurring meningiomas and 24.63% of the nuclei in atypical meningiomas.

CONCLUSION

Our results suggest that evaluation of cell proliferation using Ki67 LI, DNA ploidy and AgNOr, integrated with standard histopathology, can provide better information for a correct grading of meningiomas.