Flow cytometry in brain tumors. I. Ploidy abnormalities.

Flow cytometry (FCM) was introduced for estimation of DNA content in 75 brain tumors. Among these astrocytomas (38 cases) and meningiomas (16 cases) predominated. Astrocytomas were histologically subdivided into 3 groups of malignancy grade. Aneuploid cell populations were found in 1 out of 4 cases of astrocytoma grade I, in 11 out of 20 astrocytomas grade II and in 10 out of 14 astrocytomas grade III of malignancy. DNA index (DI) in most aneuploid astrocytomas is in the range between 1 and 2. More than one cell population with aneuploid value of DNA was found in 36% of all aneuploid tumors.