Technique for preclinical evaluation of continuous infusion chemotherapy with the use of WF rat acute myelogenous leukemia.

A technique was developed for continuous iv infusion chemotherapy in an inbred rat model of acute myelogenous leukemia. Polyethylene tubing was inserted surgically into the internal jugular vein of adult WF rats, burrowed sc to the base of the tail, and connected to an infusion pump. A flexible spring was sutured at the base of the tail and fastened to the cage wall; it protected the infusion catheter and allowed movement of the rat within the cage. This technique was used to compare bolus with continuous infusion therapy with adriamycin, cytosine arabinoside, and neocarzinostatin. Only small differences were noted in host toxicity and in antitumor effect against tumor grown as a subcutaneous myeloblastoma. Nearly three times more neocarzinostatin was required by continuous infusion for an effect equivalent to that of bolus injection. In contrast, continuous infusion of methotrexate with concurrent thymidine infusion prevented toxicity, enhanced the antitumor effect, and prolonged survival. This infusion system should facilitate rapid preclinical evaluation of drugs considered for constant iv infusion therapy.