Diffuse low-density areas in white matter on CT scans after intracarotid ACNU infusion--report of three cases.

Since 1984, we have treated 11 malignant glioma patients with intracarotid infusion of ACNU [1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)- 3-nitrosourea hydrochloride] in addition to surgical removal and irradiation. We experienced three patients, who showed clinical manifestation of leukoencephalopathy and computed tomographic (CT) findings of diffuse low-density areas in the white matter on the side of ACNU infusion. Two of the three patients showed an additional CT finding of ring enhancement in the temporo-occipital region. The histological diagnosis of the first case was radiation necrosis, while that of the others was recurrent tumor with coagulation necrosis in the surrounding brain. Our experience suggests that intracarotid ACNU infusion increases the hazard of radiation necrosis, and the optimum dose and effective mode of administration should be evaluated.