Acceleration of the Development of Leukemias and Mammary Carcinomas in Mice by 9, 10-Dimethyl-1, 2-Benzanthracene

During comparative investigations into the reaction of different inbred strains of mice to treatment with carcinogenic hydrocarbons, it appeared in some experi- ments that leukemias or tumor formations occurred in greater numbers and earlier in the treated animals of strains in which tumors or leukemia develop spon- taneously than in untreated animals of similar strains. An acceleration of the kinds of tumors occurring in these strains was evidently involved. An account will be given in the present paper of experiments with 9,~o-dimethyl-:,2-benzanthracene ad- ministered to 2 strains of mice, a mammary carcinoma strain, dilute brown, and a leukemic strain, Aka.