抄録
Seven autopsied cases of anaplastic gliomas were examined histologically in correlation with CT findings scanned shortly before death.
Tumor cells were found to spread over almost all the heterogeneous and homogeneous low density areas in the CT scan. However, it was quite difficult to differentiate, by the absorption values, tumor tissue, tumor invading zone, anaplasia of tumor, coagulation necrosis or perifocal edema. High cellularity of tumor tissue had a tendency to show high absorption values in the plain scan. In one case, the tumor invaded diffusely almost the whole brain but the absorption values were “isodense”. There was no CT evidence to show the distribution of tumor cells.
Contrast enhancement corresponded well to vascular proliferation in the tumor tissue but not necessarily to cellularity or anaplasia of the tumors. Threre was no significant CE in the areas of highly malignant glioma where the vascularity was similar to that of the normal brain or showed only a slight proliferation. These findings suggest that the contrast enhancement in the CT scan could be explained by the vascular proliferation or angiogenetic activity of gliomas.
Sequential observation of contrast enhancement in four cases showed that the increment of coagulation necrosis corresponded to the decrement of contrast enhancement. However, viable tumor tissue was found to invade the extensive areas of low density where the degree of contrast enhancement diminished in the follow-up CT scan.
