Meningiomlarda Ki-67 Proliferasyon İndeks Pozitiflik Sınır Değeri

Meningiomas are usually slow-growing grade 1 tumors according to World Health Organization (WHO) classification. Histological and molecular criterias were defined for the determination of meningiomas of high grade and more aggressive. The proliferation activity is also considered among histopathological criterias. A commonly used parameter for determining proliferation activity is the Ki-67 index. This study was formed retrospectively to identife the positivity limit (cut-off) value of the Ki-67 proliferation index in cases diagnosed with meningioma. The Ki-67 indices of a total 190 patients diagnosed with meningioma was compared with the histological degrees of the tumors. The ROC analysis method was used in the statistical analysis for Ki-67 values. The mean Ki-67 proliferation index was found to be 3% for grade 1, 8% for grade 2 and 17% for grade 3 in the cases diagnosed with meningioma in our center. The Ki-67 proliferation index, which can be used in addition to histopathological findings in the distinction of grade 1 and grade 2 meningiomas in our laboratory, was determined as a positivity limit value of 6,5 (p>0,05).