HEMATOGENOUS DEVELOPMENT OF RAT MATURE GRANULOCYTIC LEUKEMIA—COMPARISON OF 2,7-FAA-INDUCED AND TRANSPLANTED LEUKEMIA—

The oral administration of N,'N-2,7-fluorenylenebis-acetamide (2,7-FAA) induces leukemia, especially mature granulocytic leukemia in rats. We compared the degree of infiltration of 2,7-PAA-induced mature granulocytic leukemia with that of transplanted leukemia for the purpose of proving hema-togenous development of leukemia. The bone marrow, spleen and liver were examined in the cases of diffuse lesion of 2,7-FAA-induced and transplanted leukemia. The average degree of infiltration of both 2,7-PAA-induced and transplanted leukemia was high in the bone marrow, medium in the spleen, and low in the liver. Intravenous transplantation of malignant neoplasm is an example of hematogenous metastasis. The similarity of infiltration between 2,7-FAA-induced and transplanted leukemia suggests that the former is spread by hematogenous metastasis.