Leukemoid reaction in BALB/c mice bearing primary tumors induced by 3-methylcholanthrene.

During the growth of five of ten primary tumors that were induced by 3-methylcholanthrene in BALB/cMk and BALB/cMk X C57BL/6F1 mice, leukemoid reactions, characterized by increase in number of granulocytes in peripheral blood, and splenomegaly were observed. However, no such reactions occurred in five C57BL/6 mice bearing primary tumors induced by 3-methylcholanthrene. The results of leukemoid reactions in mice bearing 3-methylcholanthrene-induced primary tumors are compared with the reactions found in mice bearing transplanted tumors.