Proliferative potential and malignant transformation of ganglioglioma: immunohistochemical studies by MIB-1 and p53 staining.

We studied two cases of ganglioglioma immunohistochemically by MIB-1 and p53 staining. The positive rate of MIB-1 in the ganglionic cells was 5.5% in Case 1 and 7.8% in Case 2, and that of MIB-1 in the gliomatous cells was 1.4 and 6.6% respectively. The labeling index of p53 in the ganglionic cells was 7.3% in Case 1 and 7.7% in Case 2, and that of the gliomatous cells was 1.9 and 3.4% respectively. MIB-1 and p53 did not stain ganglionic precursor cells. These results indicate that the ganglionic cells also take part in proliferation and have potential of malignant transformation.