[Role of blood platelets and prostaglandins in blood-borne metastases].

Coagulation-fibrinolysis system, especially blood platelets, plays an important role in the stage of lodgement of circulating tumor cells. In this paper, we discuss that some tumor cells induce platelet aggregation in vitro and several anti-platelet drugs inhibit not only platelet aggregation in vitro but also tumor blood-borne metastases in vivo. For the therapy against cancer metastases, the role of blood platelets in blood-borne metastases should be clarified.