[Analysis of malignancy of human brain glioma with silver colloid-staining technique]

The nucleolar organizer regions are loops of DNA that exist in cellular nucleolus and possess ribosomal ribonucleic acid genes. Ribonucleic acid polymerase I acts on these areas. This experience collects 52 primary human gliomas at TSGH from 1984 to 1989. These included 23 astrocytomas, 8 anaplastic astrocytomas and 21 glioblastoma multiforms. After thin cutting on slides and deparaffinizing, we stained each by the silver colloid technique. We counted the total quantity of Ag-NOR dots of over 400 tumor cells of each case and average of Ag-NOR dots per cell (+/- standard error of the mean) with X1000 oil lens. The results are 1.68 +/- 0.05, 2.00 +/- 0.10; 2.55 +/- 0.13 respectively, showing significant differences among these. The average Ag-NOR paralleled the degree of histopathological malignancy. With the average Ag-NOR of tumor cells to predict the patients prognosis, we found that the group containing patients with less than 2.00 Ag-NOR per cell had better prognosis than the group with 2.00 Ag-NOR or more. The silver colloid-staining technique is a simple, rapid and reproducible method to evaluate the malignancy of human brain gliomas and to estimate the long-term prognosis of patients.