Effects of tranexamic acid and urokinase on hematogenous metastases of Lewis lung carcinoma in mice.

When Lewis lung carcinoma with low thromboplastic and low fibrinolytic activities was implanted subcutaneously to mice, administration of tranexamic acid inhibited metastasis formation in the lungs. This effect was considered to be mediated by prevention of cell release from the implanted sites. Fibrin formation around tumor cells in the vessels of primary foci was observed in the mice given tranexamic acid. On the other hand, urokinase significantly enhanced pulmonary metastases and many free tumor cells were observed intravascularly in primary foci of the mice given urokinase.