Heparin, dextran 1000 and metastasis formation after I.V. tumour cell injection in dextran non-sensitive rats

The present study of the effect of heparin and dextran 1000 on the metastasis formation after i.v. tumour cell injection in dextran non-sensitive rats using a syngeneic 20-methylcholanthrene induced fibrosarcoma showed that heparin treatment decreased with formation of pulmonary metastases in animals both untreated and treated with dextran 1000. Treatment with dextran 1000 increased the formation of pulmonary metastases in animals both untreated and treated with heparin and the effect of dextran 1000 was thus not affected by heparin treatment. Heparin did not have any direct action on the tumour cells, which influenced metastasis formation. The data suggest that heparin acts as an anticoagulant with decreased microthrombus formation around lodged cells and that dextrax 1000 stimulates metastasis formation primarily by mechanisms other than intravascular coagulation.