DNA in human glioblastomas. A flow-fluorescence cytometrical examination of 96 tumors.

The Flow-Fluorescence Cytometric Method (FCM) was applied to investigate the DNA content and the ploidy outlines of each of 96 glioblastomas. No specific DNA pattern was detected, possibly because of the tangle morphology of these variable tumors. Due to their capricious growth the DNA distribution proved to fluctuate greatly. Thus, the series, arranged according to increased PI (proliferation index) values, exhibited a wide spread within a total range from 7.1-97.15% (mean 39.3%) PI. A threefold subdivision of main types (I-III) appears to be of practical use for clinical prognostic assessment: "diploid" tumors with a PI range up to 10% (N = 7) are followed by "abnormal" chiefly tetra- and hyper-tetraploid tumors up to PI values about 30% (N = 21). The third category includes cases showing excessive "aneuploidy" combined more and more with polyploidy and valid stemlines, up to the PI maximum of about 97 rel.% (N = 68). Thus, in 89 tumors clear pathological changes of DNA content can be decoded; of these 68 (76.4%) express a considerable aneuploidy and polyploidy respectively.