DNA content of meningiomas.

Flow cytometric DNA analysis was carried out in 35 meningiomas. Thirty-three had diploid stem lines while two were aneuploid having a triploid DNA mode. Both aneuploid meningiomas were grossly huge nodular tumours and one had malignant histologic features. Flow cytometry in meningiomas is a rapid means of determining the DNA modes and adds objective information to microscopy. Appropriate cases may be selected for further cytogenetic studies.