Effect of free and bovine fibrinogen-bound methotrexate and dibromoaminopterin on the dissemination of solid Gardner lymphosarcoma.

Solid Gardner lymphosarcoma transplanted subcutaneously to mice of strain C3H/Sumice does not grow solely at the site of inoculation, but disseminates also to remote tissues. An i. v. administration of fibrinogen-Methotrexate derivative or Methotrexate (8-15 mg antimetabolite per 1 kg) to mice with an early tumor, reduced the weight of the local tumor, prolonged their survival time and also the posttransplantation period during which the dissemination of malignant cells could not be detected. When the above substances were given to mice with advanced tumors whose dissemination could be reliably established, Methotrexate proved more effective than its fibrinogen derivative. 3.5'-dibromoaminopterin administered alone or bound to fibrinogen (14.6 mg of antifolate per kg) showed no effect both on survival rate and on tumor dissemination.