Forty-one
astrocytomas of different grades were studied by means of image analysis technique for measuring
DNA content in situ, and in 28
tumors the numbers of nucleolar organiser region (NORs) associated
proteins were also determined, and 12 cases of
astrocytoma in frontal lobes were followed up. The results showed that the distribution of
DNA content in
grade I astrocytoma was 2C-4C, the peak values of
grade I astrocytoma was 2C; while for grade II, 3C-4C and hypertetraploid.
DNA contents of grade III and IV
astrocytomas were much higher, their histograms were dispersed with many peaks, the peak values were
aneuploid and heteroploid. The data confirm that heteroploid and
aneuploid are the marks of
malignancy. The
grade II astrocytoma which possesses these features has a tendency to higher
malignancy. Twenty-eight
astrocytomas were stained by Argyrophil (Ag-NOR) for NOR associated
proteins. The largest numbers of Ag-NORs were seen in grades III and IV
astrocytoma (mean 11.71), and their Ag-NORs were irregular.
Grade I astrocytoma possessed the fewest Ag-NORs (mean 6.5) which were small and uniform. The results suggest that the number of Ag-NORs is associated with the differentiation. The prognosis is significantly correlated with the numbers of Ag-NORs and the contents of
DNA in
astrocytomas.