Chemotherapeutic remissions in Wistar Furth rat acute myelogenous leukemia: a model for human AML.

Acute myelogenous leukemia (AML) of the inbred Wistar/Furth (W/Fu) rat is pathophysiologically similar to human AML. Subcutaneous transplantation of 1.0 X 10(6) cells of a clonal tissue culture line of W/Fu AML into 6- to 8-week-old rats produced local myeloblastomas in 8--10 days which progressed to infiltration of regional nodes, replacement of greater than 90% of the bone marrow, ascites, and fatal peripheral blood leukemia with concomitant hyperlysozymemia. Single doses of adriamycin, daunomycin, actinomycin, cytosine arabinoside, or Cytoxan in rats with 1.0 cm myeloblastomas produced complete tumor regression while bu-sulfan, vinblastine, vincristine, dexamethasone, and Methotrexate was relatively ineffective. Responses were associated with delay in progression to peripheral blood leukemia and prolonged survival. Similar results were obtained following treatment of rats with already disseminated leukemia. The demonstration of response to drugs known active against human AML indicates that the W/Fu AML should be a valuable model for rapid evaluation of new chemotherapeutic agents for clinical use.