Site of origin of 2,7-FAA-induced rat leukemia

Oral administration of N,N'-2,7-fluorenylenebis-acetamide (2,7-FAA) induces mature granulocytic and erythroblastic leukemia in rats. We compared the primary site of mature granulocytic leukemia with that of erythroblastic leukemia. The nodular foci of solitary lesions and comspicuously large foci of scattered lesions were considered to be the primary site. They appeared mainly in the bone marrow of various bones. The primary site of mature granulocytic leukemia appeared more frequently in short bones than in long bones. On the contrary, that of erythroblastic leukemia appeared more frequently in long bones than in short bones. The origin of mature granulocytic leukemia seems to be concerned with bone tissue, while erythroblastic leukemia may have little relation with bone tissue.