Brain tumor chemotherapy using a rat glioma model.

The antitumor agent chloroethylcyclohexyl-nitrosourea (CCNU) was examined using a rat glioma model. A i.p. administration of three times 40 mg/kg CCNU was highly effective and increased the life-span of tumor-bearing rats from 53 to 86%. A total quantity of CCNU amounting to less than 30 mg/kg was not effective. On the other hand, large dosages exceeding LD10 proved to be toxic. The depression of platelets and white blood cells was mild after a single dosage of 40 mg/kg CCNU which recovered on about the 6th day. In the CCNU-treated animals there was an increase of the extent of necrobiosis. Ballooning of tumor cells with nuclear pyknoses and a lack of mitotic features occurred. Microcystic changes appeared sometimes to be more frequent than in control groups.