Prognostic significance of nuclear DNA content in human meningiomas: a prospective study.

Flow cytometric DNA analyses were performed to study the correlation between alterations of nuclear DNA content and clinical aggressive tumour behaviour in 134 cranial meningiomas. Forty-one meningiomas revealed an aneuploid DNA content with a distribution of n = 24 in benign, n = 12 in atypical and n = 5 in anaplastic tumours. Aneuploid DNA content was correlated with a significantly higher amount of histomorphological criteria like evidence of mitoses, necrosis, infiltration and increased cellularity. There was a significantly higher Ki 67 proliferation index in the aneuploid meningiomas in comparison to the diploid tumour group. The rate of aneuploid cell-lines was increased in recurrent tumours. No tumour recurrence could be found in diploid meningiomas during follow up (mean 37 months, range 22-46 months). However eight of forty-one aneuploid tumours showed meningioma recurrence. Nuclear DNA content has an important significance in predicting risk of recurrence and poor clinical outcome after benign meningioma surgery.